Energy Conservation Procedures andEnergy Conservation Technologies

Energy Conservation
Guidebook for Factories
2021

The Energy Conservation Center, Japan

The Guidebook has been prepared by the Energy Conservation Center, Japan as a partof energy conservation support for the purpose of providing information so that small- andmedium-sized businesses can address energy conservation autonomously.
It includes the energy conservation procedures, basic energy conservation measures andeffect estimation, tuning method, and so on. Together with our other energy conservation
support measures, we hope you will make use of the Guidebook to improve your energy
efficiency.

Contents
Ⅰ. Significance and Procedures of Energy Conservation
1. First-step Energy Conservation Activities for Carbon Neutrality .......................................................................................... 1
2. Energy Conservation Procedure .......................................................................................................................................... 2
3. Energy Conservation Check List for Factories ..................................................................................................................... 3
4. Utilization of Energy Audit .................................................................................................................................................... 7

Ⅱ . Energy Audit of Factories and Results
1. Outline of Audited Factories ................................................................................................................................................. 8
2. Number of Audit Cases by Type of Industry ......................................................................................................................... 9
3. Energy Intensity by Type of Industry .................................................................................................................................. 10
4. Improvement Proposal Items by Audit................................................................................................................................ 12
5. Energy Conservation Potentials by Type of Industry.......................................................................................................... 13
6. Presentation Meeting of Energy Audits and Technologies ................................................................................................. 13
7. Utilization of Energy Conservation and Power-saving Portal Site ...................................................................................... 14

Ⅲ . Energy Conservation Improvement Proposals
A. Energy Conservation Activities, Management Structure, etc.
Case A-1: Energy Conservation Activities Approached by All Employees ....................................................................... 15
Case A-2: Approach to the Energy Conservation Activities as Part of Management Reform .......................................... 16
B. Air Conditioning and Freezing/Refrigeration Facilities, etc.
Case B-1: Optimizing the Setting Temperature of the Freezer ........................................................................................ 17
Case B-2: Replacing the Air-cooled Chiller with the Heat-Cold Simultaneous Feed Heat Pump .................................... 18
C. Pumps, Fans, Compressors, etc.
Case C-1: Inverter-based Flushing Pumps ...................................................................................................................... 20
Case C-2: Inverter-based Scrubber Fan .......................................................................................................................... 22
Case C-3: Preventing the Leak from the Air Piping.......................................................................................................... 23
Case C-4: Reducing the Compressor Discharge Pressure.............................................................................................. 25
Case C-5: Replacing the Compressor with the Roots Blower.......................................................................................... 27
Case C-6: Pulsed Air Blow............................................................................................................................................... 28
D. Boilers, Industrial Furnaces, etc.
Case D-1: Thermal Insulation for the Steam Valve .......................................................................................................... 29
Case D-2: Replacing the Boiler for Higher Efficiency....................................................................................................... 31
Case D-3: Recovering the Steam Drain........................................................................................................................... 32
Case D-4: Improvement of Combustion Air Ratios of Industrial Furnaces....................................................................... 33
E. Lighting Facilities, Power Leveling Facilities, etc.
Case E-1: Replacing the Mercury Lamps of the Factory Warehouse with the LED Lighting ........................................... 35
Case E-2: Power-saving and Energy Conservation by Demand Monitoring.................................................................... 36
F. Production Processes, etc.
Case F-1: Recovering the Waste Heat of the Powder Coating Drying Furnace .............................................................. 38
Case F-2: Reducing the Radiation Losses from the Opening of the Casting Melting Furnace........................................ 39
G. Solar Power Generation, etc.
Case G-1: Introducing the Self-consumption Solar Power Generation System............................................................... 40
Reference
Description of the common matters ................................................................................................................................. 41

Ⅰ

Significance and Proceduresof Energy Conservation· Fundamental measure for carbon neutrality
Toward "carbon neutrality" intended for zero emission of greenhouse gas totally by 2050, energy conservation as well as
introduction of renewable energy is a fundamental measure for low carbonization and decarbonization.

Economic viewpoint· Cost reduction"Profits" can be secured by the costs saved by energy conservation. This effect is similar to a sales increase. Once anenergy conservation measure is taken, its effect continues for years.

· Compatibility with improved productivity

Primary energy supply

Energy conservation and CO2 reduction are made compatible with improved productivity by reviewing production andservice methods, rationalizing a production line and providing services more efficiently from a viewpoint of energy
conservation.
Energy85％

Thorough energy
conservation
Reduction of totalenergy used including
non-fossil energy

consumption

Fossil energy

15％
Currently[Reference]
Energy Consumption
Trend in Japan

2050

2030

Introduction of renewableenergyExpansion of non-fossil
energySolar power, solar heat,biomass, hydropower,
nuclear power

Transition of Final Energy Consumption and Actual GDP
GDP
FY1973-FY2019
2.6 times（EJ）
18

Compared with the first oil crises
in 1973, total energy consumption
has been restrained toapproximately 1.2 times withrespect to the growth of the GDP,approximately 2.6 times; theindustrial sector has decreased its
ratio (0.8 times) and commercial(2.1 times), household (1.8 times)
and transportation (1.7 times)
sectors have increased theirratios.

(In trillion yen, price in 2015)
60 0

15

50 0

Transportation sector
12

40 0

Household sector
930 0Commercial and other sectors

Transportation sector

1.7 times
Household sector

1.8 times
Commercial andother sectors

6

Industrial sector

3

Final energy consumption
FY1973-FY2019

Ⅱ Energy Audit of Factories andResults

Social viewpoint

Ⅲ Energy Conservation
Improvement Proposals

Of energy environmental issues, the most crucial one will be to realize "carbon neutrality" toward 2050. To this end, it isimperative to switch fossil fuels accounting for the most of current energy supply/demand to carbon-free energy such as
renewable energy, while moving forward with thorough energy conservation.
The first-step energy conservation activities for "carbon neutrality" have the following advantages.

Ⅰ Significance and Procedures ofEnergy Conservation

1. First-step Energy Conservation Activities for Carbon Neutrality

20 0

2.1 times

Corporate,
office andothersectors

10 0

0.8 times

1.0
time

1.2 times as a whole0019731975

1980

1985

1990

1995

2000

2005

2010

2015

2019

Source: "Energy White Paper 2021" (Fig. [No. 211-1-1]), Ministry of Economy, Trade and Industry

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1

2. Energy Conservation Procedure(1) Energy conservation technologies

Energy conservation technologies are intended to enhance energy usage efficiency and widely available for improvementof usage and energy management methods as well as higher equipment efficiency. Main items are shown in Section 3"Energy Conservation Check List".
"Energy optimized audit" provided by the Energy Conservation Center, Japan and presented in Section 4 is optimal to thebusiness operators who are going to address energy conservation.

(2) Energy management

Energy conservation requires implementation of steady energy management. Enhance a management structure, visualize
energy consumption and improve operation and maintenance of facilities, equipment, etc.

Management structure▪ Declaration of intention of top management ▪ Organization(duty assignment) ▪ Human resource development, etc.

Visualization of energy consumption

Operation management▪ Operation management
standards▪ Review of the standards,
etc.

Operation manual

Energymanagement
items

Maintenance management▪ Maintenance management standards▪ Repair and renewal plan,etc.

▪ Data-sharing▪ Understanding and analysis ofdata▪ Energy intensity management,
etc.

Visualization

Measurement and recording▪ Energy consumption▪ Facility operating condition,
etc.

Measurement and recording

Maintenance management(3) PDCA

It is important to continuously upgrade energy management efforts through a PDCA cycle.

VerifyImplement

Implement an
improvement plan.
Manage aprogress.

Energymanagement
PDCA

Understand the effects.
Analyze differencesfrom the goals.

PlanManagement structure
Status quo analysis
Goals, improvement plan

2

Review

Review the improvement plan.
Review the management
method.

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3. Energy Conservation Check List for Factories
As the first step of energy conservation efforts, begin with [I] What can be implemented in daily
operations, etc. As the next step, proceed from [II] Self-practicable efforts based on an expert's advice to[III] Efforts requiring capital investment.
[Legend] I. Efforts practicable in daily operations (almost no technological hurdle)
II. Self-practicable efforts (requiring technological knowledge such as short-term measurement, etc.) based on an expert's advice
III. Efforts requiring capital investment

2. Measurement,
recording andmaintenanceDo you have a system capable of continuing energy conservation
activities (energy conservation committee, etc.)?

○

Do you implement PDCA for energy conservation activities on the premise of participation of the management? [Case A-1] [Case A-2]○

Do you decide a responsible person or a leader who promotes energy conservation? [Case A-1]○

Do you set energy conservation goals (reduction of XX%, reduction of XX tons, etc.)? [Case A-1] [Case A-2]○

Do you post the energy consumption status so that employees can understand? [Case A-1] [Case A-2]○

Do you set a policy and implementation plan for energy conservation measures?

○

Do you educate the personnel and conduct an energy conservation awareness campaign? [Case A-2]○

Do you observe Cool Biz*1 and Warm Biz*2?

○

Do you secure a time and a budget for addressing energy conservation?

○

Do you manage documents such as an equipment ledger and drawings?

○

Do you identify the energy conservation equipment to be concentratedly managed? [Case A-2]○

Do you have the operation records (daily reports monthly reports, etc.) of main facilities?

○

Do you decide the management values for checking the operating status and their ranges?

○

Do you conduct daily inspection and maintenance of the facilities?

○

Do you have the Energy Management Manuals of main facilities (air conditioning, ventilation, lighting, production facilities, etc.)?

○

Do you periodically calibrate the measuring instruments?

○

Do you periodically clean and replace the filters, strainers, etc.?
○

Do you periodically repair the piping, etc. and check for a leakage (water, steam, compressed air, etc.)?
Do you aggregate (graph, etc.) and visualize monthly and annual energy consumptions?
[Case A-1] [Case A-2]○
3. Energy
management○

Do you measure and record energy consumption by type and usage purpose to always monitor (visualize)?

○Do you measure hourly power consumption to manage peak power?

○

Do you analyze the energy consumption status in view of the outside temperature, production volume, etc.?

○
4. Energy intensity,
etc. management[2] Air conditioning, ventilation, freezing andrefrigeration facilities[Case A-1]

Do you consider merger of production process management and energy management (reduction of fixed energy, etc.)?

○

Do you calculate the unit prices of energy common to business establishments (e.g.: yen/kWh, yen/liter, yen/m3)?

○

Do you manage the energy intensity ("energy consumption/production volume", "energy
cost/production volume", etc.)?
○

Do you manage the energy intensity and cost by process, product and department?

○

Do you properly manage the room temperature and humidity according to the season?

○

Do you set weekly and annual rules and observe the scheduled operation?
○

1. Management of
the air conditioning
facilities

2. Energy
conservation
measures for air
conditioning[Case A-1] [Case A-2]

Do you relax the cold water outlet temperature when a cooling load is low?
○

Do you shut off an entry of outside air such as draft in an air-conditioned area?

○

Do you control an outside air introduction rate?

○

Do you control the number of heat source equipment (chillers, etc.)?

○

Do you implement local exhaust or radiation shutoff with respect to the heat-generating equipment?

○

Do you take an anti-solar radiation measure for the windows (planting by the windows, blinds, curtains, etc.)?

○

Do you periodically clean the filters and the fins of outdoor units?

○

Do you shield the outdoor units from the sunshine and sprinkle water to them in summer?
○

Ⅰ Significance and Procedures ofEnergy Conservation○

Ⅱ Energy Audit of Factories andResults[1] General management items

1. Energy
management
organization

Check item

Ⅲ Energy Conservation
Improvement Proposals

Ⅰ Ⅱ Ⅲ

Classification

Have you utilized cooling with outside air when cooling is required during an intermediate period or winter?
○Do you apply a heat-shielding paint to the roof and plant on the rooftop?

○

Do you employ the walls and ceilings, etc. with high insulation?

*1 Cool Biz: Japanese government campaign encouraging the people to wear lighter clothes and the companies to set their air conditioners to 28°C
*2 Warm Biz: Japanese government campaign encouraging the companies to set their heater thermostats to 20°C during the winter

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3

Classification

Ⅰ Ⅱ Ⅲ[2] Air conditioning, ventilation, freezing andrefrigeration facilities○
2. Energy
conservation
measures for air
conditioning

Is it possible to reduce an air-conditioned area (partitions, lining of the high ceiling, etc.)?

○

When there are not many people in a spacious air-conditioned area, do you use a spot cooler?

○

Do you recover and utilize the waste heat?

○

Do you upgrade to the high-efficiency air conditioning facilities?
Do you stop ventilation of an unused area or when not used?

○

Do you implement room temperature control operation for electric room, machine room, etc.?

○

Do you adjust a ventilation rate by proper ventilation frequency and intermittent operation, etc.?

○

Do you change an outside air inlet rate according to the season?
○

Is the facility internal temperature adequate?

○

Are the cold water inlet and outlet temperature/pressure and the refrigerant inlet and outlet pressure adequate?

○

Do you manage the cooling water quality (electrical conductivity)?

[3] Pumps, fans and compressors

1. Management of
the pumps andfans

Can you reduce frequency of defrosting according to the season?

○

Do you control a flow rate for the pumps of the chiller and cooling tower (introduction of an inverter, etc.)?
○

Do you reduce frequency of a door opening/closing, shorten an opening time, install an air curtain, and so on?

○

Do you reduce heat generation of facility internal lighting (e.g. introduction of LEDs)?

○

Are there any frozen parts due to heat insulation failure in heat insulation treatment of the wall surface, ceiling, piping or door?

○

Do you introduce the high-efficiency refrigeration and freezing facilities?

[Case B-2]

Do you check opening and closing of the valves daily (prevention of forgetting to close)?
○

Are the working flow rates (airflow, water flow) and pressure adequate?

○

Aeration tank blower: Do you operate intermittently and/or reduce an airflow rate on holidays and during nighttime?
○

Do you implement the inverter-based rotating speed control for flow rate? [Case C-1] [Case C-2]○

Do you adjust a flow rate, using units control and sensors according to a load?

○

Are the route and size of piping and duct adequate?

○

Do you check opening and closing of the valves daily (prevention of an air leak due to forgetting to close)?

○

Do you clean the filter at the air inlet port?

○

Do you optimize the discharge pressure and working-end pressure?

[Case C-4]
[Case C-3]

2. Management of
the compressors○

Do you inspect and repair an air leak?

○

Do you optimize an air blow rate (nozzle structure, blow time, etc.)?

○

Are the compressors exhausting outdoors (measure to lower the feed air temperature)?

○

Have you checked whether the size and route of piping are adequate?
○

Do you optimize the model, capacity and number of operating units and control the number of units according to a load?

○

Do you install an air receiver when the load fluctuates greatly?

○

Do you classify into the high- and low-pressure lines?

○

Have you changed aeration for cooling and purging to the blowers, etc.?

[Case C-5]○

Have you considered pulsed air blow?

[Case C-6]○

Do you reduce a pipe resistance (bypass piping) or conduct looping (consideration of pressure loss, etc.)?

○

Can you upgrade to the high-efficiency compressors (inverter-based control of a flow rate, etc.)?

○[4] Heat facilities such as boilers andindustrial furnaces[Case B-1]

○

○

4

Do you implement local exhaust as an excessive exhaust control measure for the entire room?

○

4. Refrigeration andfreezing facilities

Do you periodically check whether the air ratio and exhaust gas temperature are adequate? [Case D-4]○

1. Management of
the combustion
facilities

Do you carry out maintenance and inspection of the burners (cleaning, replacement of worn)?
○

Do you consider optimization of the burner capacity according to a change of the load capacity, etc.?

○

Do you reduce the heat capacity of the furnace body and furnace internal carrier?

○Is the combustion control unit operating stably?

○

Is a ventilation rate fully secured?
○

2. Heat retention andradiation
prevention of thefurnaces, ducts,
heat facilities, etc.

Do you implement the inverter-based control of a flow rate for heat transfer machines (pumps, blowers) according to a load?

○○
3. Ventilation
facilities

Check item○

Do you upgrade to the high-efficiency models?

[Case D-2]

Do you check whether the thermal insulation materials of the furnace wall are adequate and have no damage?
○Is the furnace internal pressure properly controlled (prevention of hot gas blowout and entry of the outside air, check for the opening, scale-down)?

○

When the temperature of the furnace wall outer surface and exhaust duct is high, have you taken a thermal-insulating/heat-retaining measure?
○

Do you take a thermal-insulating/heat-retaining measure for the high-temperature facilities?

○

Do you fully scale down or seal the opening of the furnace?

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[Case F-2]

○Do you check whether the capacity of the combustion facilities is adequate (load factor, start/stop status)?

○[Boiler] Do you periodically measure and record the steam pressure/flow rate, blow rate, etc.?

○[Boiler] Do you make efforts to ensure an optimum blow rate by managing the water quality, and so on?
○[Boiler] Can you set the steam pressure lower?

○[Boiler] Do you implement manual adjustment/automatic control to ensure the efficient number of operating units?

○[Boiler] Do you introduce an accumulator when the load fluctuates greatly?

○[Boiler] Do you consider introduction of the high-efficiency boilers?

4. Management of
the steam system
and waste heatrecovery

Piping system and load facilities: Do you check for a steam leak and an improper heat-retaining measure? [Case D-1]○

Do you periodically inspect and replace a steam trap?

○

Is the piping size adequate? Is there any unnecessary piping?
○

Have you considered integration of multiple steam systems?

○

Do you recover steam drain?

○○

5. Heat recovery of
exhaust gas andreduction ofdrainage

Do you utilize flash steam?
Do you circulate and utilize cooling water?

○

Do you recover the waste heat of combustion exhaust gas?

○

Do you circulate and utilize the exhaust gas?

○

Do you recover the heat of hot waste water?

○[Case F-1]

Has temperature efficiency worsened?
○

Do you carry out periodic maintenance and inspection (contamination, clog, etc.)?
○○[5] Lighting, power receiving and transforming facilities, electric facilities[Case D-3]

Do you consider introduction of the high-efficiency heat exchangers?
Do you decide and manage a luminosity standard for each room?

○

Do you turn off the lights by the windows (utilization of daylight)?

○

Do you turn off the lights when they are unnecessary such as in an empty room and during a lunch break?

○
1. Management and ○energyconservation of thelighting facilities

Do you adjust the lighting time and number of outdoor lights according to daylight hours?
Do you clean the lighting apparatuses and replace the old lamps?
○

Toilets, warehouses, etc.: Do you use a motion detector to turn on/off the lighting?

○

Are the lighting fixtures properly positioned (height and layout) with respect to required luminosity?
○

Do you subdivide a lighting circuit to turn off the lights in an empty area, etc.?

○

Do you dim or turn off the lights with automatic dimmer control?

○

Do you replace with LED lighting?

○○

2. Management andenergyconservation of thepower receiving○
and transforming
facilities[Case E-1]

Have you considered task ambient lighting? (All-room lighting → Overall + Hand lighting)Do you manage power consumption for each department (monthly and daily) (understanding of the actual situation, graph, etc.)?

○

Do you use a demand monitoring device to reduce contract demand?

○

Is the power-receiving end of the electric equipment at the rated voltage (necessary to adjust the voltage when too high or low)?

○[Case E-2]

Is a power factor adequate (e.g. a measure is necessary if it is less than 95%)?
○

When load fluctuations are great (low nighttime power, etc.): Do you install an automatic power factor regulator?
[Transformer] Do you shut off the primary-side power of an unnecessary transformer?

○[Transformer] When a load factor has a margin, do you integrate the transformers or optimize the transformer capacity?

○[Transformer] Do you strike a load balance among three phases?

○[Transformer] Do you examine the load factor to level the load (load control)?
○○
3. Energy
conservation of theautomatic vending ○machines○
4. Management of
the OA equipment

Ⅰ Significance and Procedures ofEnergy Conservation[Boiler] Do you level a steam load?
○○

6. Management of
the heatexchangers

Check item

Ⅱ Energy Audit of Factories andResults

3. Operation andefficiency
management

Ⅰ Ⅱ Ⅲ

Ⅲ Energy Conservation
Improvement Proposals[4] Heat facilities such as boilers and industrial furnaces

Classification[Transformer] Do you upgrade to the high-efficiency transformers?
Do you turn off the backlight?
Do you stop operation on holidays and during nighttime (timer function)?
Do you request a supplier to upgrade to an energy-saving type (heat pump type, etc.)?

○

Do you turn off the power when unnecessary (holidays, etc.)? (Except for fax machines)○

Do you set to the energy-saving mode (nighttime/holidays)?
○

Do you replace with a power-saving type?

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5

[6] Electric motors and electric heating facilities

Classification

Ⅰ Ⅱ Ⅲ
○

1. Management of
the 3-phaseinduction motor,
etc.

Do you notice abnormal heating or noise of the electric motors?

○

Do you check whether the supply voltage and rotating speed of the electric motors are adequate?
○

Do you prevent no-load operation (idling)?

○ Are they operated according to a load (inverter-based rotating speed control, unit numbers control)?
○ Do you introduce the high-efficiency motors (including permanent-magnet motors)?
○

Do you check whether the power factor is adequate?

○

Do you control the thermal insulation and heat retention of the furnace wall?

2. Management of
the electric heating
facilities○

When the supply voltage is low, do you optimize it by reviewing a wiring size, and so on?

○

Are the heating time and temperature adequate?

○

Have you considered centralization of intermittent operation?

○

Do you shorten an opening/closing time at the entrance and exit when preheating a material and loading/unloading a product?

○ Do you enhance the load factor (reduction of heat storage losses, cooling losses, etc.)?
○ Do you scale down a lid or opening, and take a measure to reduce a furnace internal gas leak?
○[7] Production facilities
and drainage facilities

Check item

Do you turn off the facilities when a production line is stopping or when they are not operating (reduction of fixed power)?
○

1. Production
facilities

Do you shorten an idling time of the production facilities?

○ Are the products and production facilities not overcooled?
○ Do you consider introduction of manufacturing facilities with higher production capability and efficiency than conventional ones?
As for aeration tank for drainage treatment, do you reduce a blower’s air blow during a
non-operating time (nighttime and holidays)?

○
2. Drainage facilities○ Can you recover and utilize a gas at the time of methane fermentation?
○ Can you recover waste heat from hot drainage by utilizing a heat pump?
○

Have you reviewed an operation form (working hours, operation rate, load factor, etc.)?

○

Have you considered lowering demand response and raising demand response in viewof your own daily power load curve?

1. Load leveling○

Have you considered introduction of a heat storage unit?

○

Have you considered introduction of an absorption type water heater/chiller?

○

Have you considered introduction of storage batteries (lithium-ion batteries, NAS batteries, etc.)?
Do you improve the operation after checking an operating condition (dependency rate,
power generation efficiency, waste heat utilization rate, overall efficiency, etc.)?

○
2. Cogeneration○[8] Miscellaneous○Have you considered purchasing various menus of renewable energy electricity?

○

Have you considered purchasing a certification of renewable energy electric power?
○

3. Renewable energy

4. Utilization ofunused heat

Have you considered introduction of a cogeneration system (including a fuel cell-based
system)?

Have you considered introduction of wood-burning stoves and pellet-burning stoves?

○

Have you considered introduction of solar power generation?

○

Have you considered introduction of a solar water-heating system?

○

Have you considered introduction of earth thermal/underground water heat pump air conditioning?

○

Have you considered switching to heat supply by a heat pump as to a boiler?

○

Have you considered introduction of a heat source facility (boiler, water heater/chiller,etc.) based on woody biomass, etc.?

○

Have you considered the possibility of switching to electric heating (induction heating,energization heating, etc.) as to a combustion furnace?

○

Have you considered mixed combustion of hydrogen and ammonia as a fuel or switching of fuel?*○

Have you considered switching to a hydrogen burner in a combustion furnace?*[Case G-1]

Have you considered utilization of the waste heat from the equipment (compressor,
furnace) or a building (electrical room) for heating or hot water supply?

○○

Have you considered utilization of the low-temperature waste heat, etc. using a heat pumpor a binary power generator (utilization of cooling water and low-temperature exhaust gas)?

* The future fuels such as hydrogen and ammonia are the items becoming feasible after they have been introduced and spread.

6

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4. Utilization of Energy Audit

・Apply for an audit menu suitable to the usage of electricity and fuels of the factory, building, etc. to be audited.
・After confirming payment of an audit expense, our visit schedule will be coordinated to dispatch experts.
・At site, we will check the actual operating status and management status of the facility to prepare an audit report.
・We will explain the audit results at a briefing and give advice for implementation of proposals.

Application and payment

After about 2 weeks

About 1 month after audit

On-site audit

Submission of report

Audit results briefing

Audit menu

Audit A

Menu to be audited by one expert

Audit B *2

Menu to be audited by two experts(briefing held by one expert)¥9,500 (tax excluded) *1¥10,450 (tax included)¥15,000 (tax excluded) *1¥16,500 (tax included)*1 A bank transfer fee for the audit expense shall be borne by an applicant.
*2 Business establishment having a lot of equipment using the heat such as boilers and large air conditioners, or relatively large-scale business establishment(2) Business operators eligible for the audit
Those meeting one of the following conditions• Small- and medium-sized enterprises (those stipulated by the Small and Medium-Sized Enterprise Basic Act)
Those falling under *1 are excluded.
(The small- and medium-sized enterprises falling under the conditions in *1 are also acceptable if they meet the following conditions.)

Ⅱ Energy Audit of Factories andResults(1) Flow of the audit

Ⅰ Significance and Procedures ofEnergy Conservation"Energy optimized audit" conducted by ECCJ is a project by the Agency of Natural Resources and Energy, "Subsidies for
Promotion of Optimized Energy Utilization for Small- and Medium-sized Enterprises in FY2021".
Energy conservation is the most effective means for decarbonization. Moving one step further forward, "energy optimized
audit" is a new service intended to accelerate decarbonization by adding "renewable energy proposals" to reduction ofenergy consumption by "energy audit".

• Factories, buildings, etc. with annual energy consumption (crude oil equivalent) of 100 kl to less than 1,500 kl inprinciple■Application form

Select "Energy Optimized Audit" at the Energy Conservation and Power-saving portal site (https://www.shindan-net.jp),
followed by "Factory" or "Building". Particularly, in the case of a small-scale building, select and download an application
form for "Simplified Version for Buildings" and send it by e-mail, fax or postal mail to apply.

Ⅲ Energy Conservation
Improvement Proposals(Even if less than 100 kl, acceptable in case of receiving low-voltage power, high-voltage power or extra high-voltage power)*1 ① Small- and medium-sized business operators whose stocks are directly or indirectly possessed 100% by a corporate body with acapital or investment of ¥500,000,000 or more
② Small- and medium-sized business operators whose annual average taxable income of each year or each fiscal year of the mostrecent past 3 years exceeds ¥1,500,000,000■Address (Contact information)

Igarashi Building 5F, 2-11-5 Shibaura, Minato-ku, Tokyo 108-0023 Japan
Secretariat of Energy Audit, The Energy Conservation Center, Japan
Phone: +81-3-5439-9732
Fax: +81-5439-9738
E-mail: ene@eccj.or.jp
Energy optimized audit
Free dispatch of lecturer
Download eachapplication form from here

Energy Conservation and Power-saving Portal Site

* Download the application form at the website, fill in withnecessary information and send it to each secretariat bye-mail or fax to apply.

Energy audit

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7

Ⅱ

Energy Audit ofFactories and Results

The following outlines the energy audits of factories implemented by the Energy Conservation Center, Japan. Utilize
them as reference data for management of the energy consumption and energy intensity, and consideration of
improvement proposals.

1. Outline of Audited Factories
An energy conservation audit ratio of factories (FY2016 to FY2020) is shown by region and scale (capital and number of
employees). For annual energy consumption (crude oil equivalent) of the factories, a histogram is used to show its
distribution.
Kyushu,Okinawa\100,000,000 to\1 billion

3％Over 200 employees

3％\10,000,000 or less

Tohoku15％

25％\50,000,000 to\100,000,000

FY2016 to FY2020

50 to 100
employees

14％

FY2016 to FY2020

21％\10,000,000 to\20,000,000

20 to 50 employees

12％\20,000,000 to \50,000,000

Tokai

32％

27％

18％

Ratio of audits by region

Ratio of audits by capital

Ratio of audits by number of employees

2500

2500

2300

2400

2200

2000

1700

1800
1900

1500

1600

0%

1300

0

1400

20%

1200

100

1000

40%

1100

200

800

60%

900

300

700

80%

500

400

600

100%

400

500

200

120%

300

600

100

Cases

26％

19％

FY2016 to FY2020
1,583 cases
Kanto,
Koshinetsu

2％

20 employees
or less

13％

31％

16％

Hokuriku

8％

100 to 200
employees

8％

Cumulative ratio

3％

Chugoku

Kinki

Over \1 billion

4％ Hokkaido

2100

Shikoku

Energy consumption in crude oil equivalent (kl/year)

8

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2. Number of Audit Cases by Type of Industry
The following shows the number of energy audit cases (FY2016 to FY2020) by type of industry.
240

Food manufacturing industry

235

Metal products manufacturing industry

Production machinery and equipment
manufacturing industry

83

Transportation machinery and equipment
manufacturing industry

82

Textile industry

59

Electrical machinery and equipment
manufacturing industry

56

Printing and allied industries

56

Waste disposal services

49

Iron and steel industry

48

Ceramic, stone and clay products
manufacturing industry

45

Automobile maintenance services

41

Water services

37

Electronic parts, devices and electronic
circuits manufacturing industry

36

Commercial machinery and equipment
manufacturing industry
General-purpose machinery andequipment manufacturing industry

31

Non-ferrous metals manufacturingindustry

31

Miscellaneous manufacturing industries

28

Beverages, tobacco and feed
manufacturing industry

25

Lumber and wood products
manufacturing industry

25

Agriculture

25
18

Furniture and fixtures manufacturingindustry

16

Rubber products manufacturing industry

14

Laundry, beauty and bath services

11

Mining and quarrying of stone and gravel

11

Feed and organic fertilizer manufacturingindustry10

Warehousing industry

9

Food take-out and delivery services

9

Petroleum and coal products
manufacturing industry

9

Ⅲ Energy Conservation
Improvement Proposals

34

Pulp, paper and paper products
manufacturing industry

0

Ⅱ Energy Audit of Factories andResults

73

Chemical industry

Miscellaneous

Ⅰ Significance and Procedures ofEnergy Conservation

111

Plastic products manufacturing industry

26
50

100

150

No. of audit cases

200

250

300

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9

3. Energy Intensity by Type of Industry
The energy intensity is an important index for evaluating the energy management status. This is indicated by energy
consumption per production volume, etc. and calculated by the following formula.

Energy intensity＝

Energy consumption (kl in crude oil equivalent, etc.)
Volume closely associated with energy consumption (production volume, shipment value, etc.)

The following figure compiles energy intensity data obtained by the energy audits of factories and calculates their simple
averages by type of industry. In order to use an identical index for all types of industries, a crude oil equivalent value ofannual energy consumption is divided by the shipment value to be used as the index. Refer to the following values
when evaluating the energy intensity of your company.
200

Laundry, beauty and bath services

137

Mining and quarrying of stone and gravel
Ceramic, stone and clay products
manufacturing industry

109

Petroleum and coal products manufacturing industry

97

Iron and steel industry

96

Food take-out and delivery services

96

Textile industry

91

Chemical industry84

Non-ferrous metals manufacturing industry

80

Electronic parts, devices and electronic circuits
manufacturing industry

73
67

Plastic products manufacturing industry
Rubber products manufacturing industry

58

Beverages, tobacco and feed
manufacturing industry

56

General-purpose machinery andequipment manufacturing industry

54

Electrical machinery and equipment
manufacturing industry

52

Metal products manufacturing industry

51

Food manufacturing industry

48

Lumber and wood products manufacturing industry

40

Transportation machinery and equipment
manufacturing industry

36

Printing and allied industries

34

Commercial machinery and equipment
manufacturing industry

32

Pulp, paper and paper products
manufacturing industry

31

Production machinery and equipment
manufacturing industry

26

Furniture and fixtures manufacturingindustry

23
0

50

1 00

1 50

2 00

2 50

Energy intensity (kl/shipment value (in \100,000,000))

10

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The following shows the distribution of energy intensity as to 6 types of industries with more audit cases. Even within an
identical type of industry, the products range widely, resulting in a broader distribution of the energy intensity.

60

40%

20

20%
0%

30

80%

25

〜150

〜130

Average: 27

60%
40%

10

〜150

〜130

〜110

0%
〜90

0
〜70

20%

0 〜10

5

100%

80%

0
〜150

〜130

〜90

0%
〜110

Energy intensity (kl/in \100,000,000)

20%

〜70

〜150

〜130

〜110

〜90

〜70

0%
〜50

0
〜30

20%

0 〜10

5

40%

6

〜50

40%

60%

Average: 89

〜30

10

60%

0 〜10

Average: 3480%
Data count: 72

12
Cases

Data count: 81

Ⅲ Energy Conservation
Improvement Proposals

Textile industry

18

100%

15
Cases

〜110

15

Energy intensity (kl/in \100,000,000)

Transportation machinery and equipment
manufacturing industry
20

〜90

20

Energy intensity (kl/in \100,000,000)

2580%
Data count: 81

〜150

〜130

〜110

〜90

0%
〜70

0
〜50

20%

〜30

5

100%

〜50

40%

Cases

10

100%

60%

Average: 62

0 〜10

Cases

15

〜70

Production machinery andequipment manufacturing industry〜30

Data count: 110〜50

Energy intensity (kl/in \100,000,000)

Plastic products manufacturing industry
20

〜30

0 〜10

0

Energy intensity (kl/in \100,000,000)

25

60%

Average: 53

〜150

〜130

0%
〜110

0
〜90

20%

〜70

10

〜50

40%

〜30

20

0 〜10

40

60%

Average: 48

80%

Data count: 234

Ⅰ Significance and Procedures ofEnergy Conservation

80%

Data count: 237

30

100%

Ⅱ Energy Audit of Factories andResults

100%

40
Cases

Metal products manufacturing industry

Food manufacturing industry

Cases

50

Energy intensity (kl/in \100,000,000)

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11

4. Improvement Proposal Items by Audit
After investigating the status quo of the factory, theenergy audit presents an improvement proposal.
The right pie chart classifies the target facilities as to theimprovement proposals by the latest factory audits.
The following table totalizes the number of cases by
proposal for each classification of facilities. For yourinformation, you can understand what kind of
improvement proposals are presented more according to
the facility.

Industrial
Water
furnaces, drying Miscellaneous
feed/drainage,
furnaces, etc.
2.3%
sanitary facilities,
3.6%
drainage treatment
4.0%
Power receiving andLighting
transforming facilities
19.9%
6.9%
General management,
production management
8.0%
Air conditioning/ventilation,
freezing/refrigeration
Production facilities,
facilities
miscellaneous facilities
18.3%
9.9%
Steam, hot water Compressors
boilers, water
16.4%
heating, piping
10.7%(Note) Improvement proposals by energy
audits of factories

Lighting

Air conditioning
and ventilation
facilities

Replacing with LEDsThinning out the lights and turning off unnecessary lights
Replacing with LED guidelights
Optimizing the setting temperature
Upgrading to the high-efficiency equipment
Cleaning the fins of the outdoor unit
Introducing inverters for the fan and pump
Reducing the external thermal loads such as outside air and solar radiation
Cleaning the filter of the indoor unit
Reducing the standby power
Stopping unnecessary facilities

Compressors

Optimizing the discharge pressure
Preventing a leak from the air piping, etc.
Reducing an air blow rate
Upgrading to the high-efficiency equipment
Lowering the feed air temperature
Cleaning the feed air filter

Production
facilities, etc.

Introducing inverters for the pump
Introducing inverters for the fan and blower
Insulating and retaining the heat of the heating facilities, tank, etc.
Stopping unnecessary facilities
Insulating and retaining the heat of the industrial furnace, etc.
Enhancing efficiency (motor, pump, etc.)
Optimizing the setting temperature, flow rate, pressure, etc.
Optimizing the air ratio of the industrial furnace, etc.

Boilers, water
heating andpipingInsulating and retaining the heat of the piping, etc.
Optimizing an air ratio
Recovering the waste heat
Optimizing the steam pressure and temperature
Upgrading to the high-efficiency equipment

Power receiving
and transforming
facilities

Upgrading to the high-efficiency equipment
Integration and suspension

Demand control
and others

Introducing a demand monitoring system
Utilizing the demand monitoring system
Inverter-based control of the water feed and discharge pumps

0

50

100

150

200

250

300

350

Proposals

12

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400

5. Energy Conservation Potentials by Type of Industry
The following compiles the energy conservation rate of the improvement proposals based on the energy audits for eachtype of industry. This energy conservation rate is a ratio of proposed energy conservation to energy consumption of theaudited business establishment.
This figure shows an energy conservation potential for each type of industry, roughly ranging from 6 to 15%.

10.9

12.6

11.7
10.0 9.9

10

8.4

7.2

6.2

6.2

6.0

6.9

7.7

8.9

12.7

11.8

11.7

10.1
8.2

9.4
7.6

5

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fac
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0

6. Presentation Meeting of Energy Audits and Technologies
The "Presentation Meeting of Energy Audits and Technologies" has been held throughout the country since FY2014 forthe purpose of providing energy conservation technologies and information for small- and medium-sized businesses
across Japan.
It provides the information on the successful energy conservation cases with an energy audit as an opportunity, latest
energy conservation technologies, viewpoints of energy conservation promotion and specific implementation methods.
The meeting is planned online in FY2021. For the dates and details of presentation, see the Energy Conservation andPower-saving portal site "shindan-net.jp".

Appearance of the meeting in FY2019

Ⅱ Energy Audit of Factories andResults

15

Ⅲ Energy Conservation
Improvement Proposals

Energy conservation potentials (%)

15.4

Ⅰ Significance and Procedures ofEnergy Conservation

Energy業種別省エネポテンシャル
conservation potentials by type of industry

20

Held online in FY2020 (video streaming)

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13

7. Utilization of Energy Conservation and Power-saving Portal Site
Useful information is provided for promoting energy conservation and power-saving, such as introduction of audit casesand video-based tuning methods in addition to introduction of detailed energy conservation support services andapplication methods. Also, a self-audit tool allows you to compare the energy intensity with the same kind of facilities.

Energy conservation support service
Different services are presented such as the energy optimized
audit and free dispatch of lecturer. Apply for them from here.

Introduction of the energy audit cases
Based on the energy audit cases, many successful cases arepresented as to the viewpoints and specific practicable methods ofenergy conservation promotion, company-wide energy
management, approaches to energy conservation, etc. The cases
can be searched for each major type of industry, facility, energy
conservation technology, etc.

Energy audit tool for buildings
By inputting the information of your own facility, you can see theposition of energy intensity and major energy conservation
measures for the buildings of the same kind of application.

Energy conservation animation channel
Auditing and a typical energy conservation tuning method arepresented in videos for easy understanding.

Energy optimized audit
Free dispatch of lecturer
Download eachapplication form from here

14

Energy Conservation and Power-saving Portal Site

* Download the application form at the website, fill in withnecessary information and send it to each secretariat bye-mail or fax to apply.

Energy audit

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Ⅲ

Energy Conservation
Improvement Proposals

Case A-1: Energy Conservation Activities Approached by All Employees
1. Background to approaching the activities
Based on the management's conviction, "A manufacturing company should pay attention to the environment", allemployees participated in the energy conservation activities, centering on visualization of energy and elimination of waste.

2. Improvement measure
MeasureImplementation items and effects

Energy conservation promotion
structure (energy management
structure participated by all employees),
human resource development

A responsible person was decided for each management item so that all employees have theirroles in the energy conservation activities, and recording and management by objective were
implemented, thereby ensuring periodic assessment by a manger.

Setting the goal
Posting the posters

Power consumption was graphed by season and hour (Fig. 1). The effect of turning off the PCs
and lighting during a lunch break was confirmed, leading to a motivation.
The weight of waste was measured, recorded and posted for each workplace, enhancing a motivation for reduction.
While all employees were implementing the energy conservation activities, they noticed different
things for the first time, further promoting the activities.
Based on the values obtained by visualization, a specific reduction goal and an activity plan wereprepared through discussion. The plan was presented and the activity status was entered every 3months and checked by a manager.
The posters were posted for power saving, PC power-off, standby power reduction, etc.

The activities began with the following readily practicablemeasures.
・Turn off unnecessary lighting.
・Utilize remote switches to thin out lighting.
・Visualize an air leak from the piping, etc. with foams to repair
a leaking area.
・Utilize a reed screen or a curtain to prevent sunlight fromentering the room.
・Paste an insulating sheet to a glass door.

Aug.

0

1

2

3

4

5

Sep.

6

7

Oct.

8

Nov.

Dec.

Jan.

Feb.

Mar.

Ⅲ Energy Conservation
Improvement Proposals

Measurement, recording,maintenance (visualization) andmanagement of energy consumption

All employees visited the waste disposal facilities to enhance their environmental awareness.

Ⅱ Energy Audit of Factories andResults

A. Energy Conservation Activities, Management Structure, etc.

Ⅰ Significance and Procedures ofEnergy Conservation

The following describes the typical energy conservation improvement cases in the energy audits provided by the Energy
Conservation Center, Japan (the information has been changed for the public).

9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

Fig. 1 Hourly average power consumption by month

3. Results
The activities participated by all employees produced not only the effects of energy conservation, but also the following
results.
・There was a change in the employees’ environmental awareness.
・Work efficiency was improved from a viewpoint of energy conservation.
・Communications between the employees were facilitated.
・Utility costs were reduced to improve a profit rate.

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15

Case A-2: Approach to the Energy Conservation Activities as Part of Management Reform
1. Background to approaching the activities
Under the management’s policy, "Enhance efficiency of production activities as well as eliminate energy waste", theenergy conservation activities began with visualization of energy which leads to enhancement of the employees’
awareness.

2. Improvement measure
MeasureImplementation items and effects"What is actually wasted" was shown to the employees to notify that they can do it if they try.
Waste, namely power consumption on holidays, was "visualized" and it was habituated to turn off
the circuit breakers on the weekends to greatly reduce power consumption on holidays (Fig. 1).

Energy conservation promotion
structure(Full-participation energy
management structure)

As a result of quantifying the effect by implementing readily practicable matters such as turning off
unnecessary lighting, controlling the air conditioner's temperature setting and operating time
thoroughly, and repairing a leak from the compressed air piping, the employees were motivated toactively approach the energy conservation activities at each workplace (Fig. 2).
With scores of wattmeters installed, power consumption for each facility was "visualized" by an
in-house data collection system to check daily. Importance of "visualization" was realized.

Measurement, recording,maintenance (visualization),energy consumption management
and human resource development

An "Energy Conservation Committee" was launched to clarify the scope of power management foreach department, and a PDCA cycle for energy conservation was advanced for sure throughpower audit, improvement, monthly report, etc.
Young employees were elected for the "Energy Conservation Committee" for each department
and instructed by external experts.

As a result of approaching the following readily practicable measures, there were the effects of energy conservation
beyond the management's expectation.
・Turning off unnecessary lighting
・Controlling the air conditioner’s setting temperature and operating time thoroughly・Investigating and repairing an air leak from the compressed air piping
・Optimizing the compressor discharge pressure

Fig. 1 Indication for easy lights-out check

Fig. 2 Posting wasted power consumption
due to air leak

3. Results
By visualizing actual waste to show the effects of reducing standby power, turning off unnecessary lighting, and so on,each workplace built a structure to actively approach the energy conservation activities.
Management’s comment:
It is important to maintain the employees’ motivation and visualize energy consumption and the results of activities.
We would like to actively introduce energy-saving equipment down the road.

16

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B. Air Conditioning and Freezing/Refrigeration Facilities, etc.
Case B-1: Optimizing the Setting Temperature of the Freezer

Control the freezer temperature at the setting criterion of –25°C. The evaporation temperature of a refrigerant can beincreased by increasing the setting temperature, thereby improving efficiency of the chiller and reducing power
consumption.

3. Effect estimation

Controller(1) Calculation formula
Current power consumption: Chiller motor capacity (kW) x Motorload factor (%) x Operating time (h/year)
Power consumption after improvement: Power consumption(status quo) x Ratio of current power to improved power(2) Prerequisites for calculation
Chiller motor capacity: 27 kW (refrigerant: R-404A)
Motor load factor: 60%
Freezer temperature: –28°C for the moment, –25°C after
improvement
Refrigerant evaporation temperature: 10°C lower than the
refrigerator temperature
Refrigerant condensation temperature: 35°C
Operating time: 24 h/day x 365 days/year = 8,760 h/year
Ratio of current power to improved power: 88% (power ratio drops
to 88% by alleviating the temperature by 3°C)

Indoor unit

Refrigerant
pipingFig. 1 Freezer

Outdoor unit

4. Effects① Power consumption (current)

141,900

kWh/year②

Power consumption (improved)

124,900

kWh/year③ Reduced power consumption④ Energy conservation rate
⑤ Saved amount of money

17,000⑥ Reduction in crude oil equivalent⑦ CO2 reduction*

kWh/year

①−②

12

%

③/①

323

\1,000/year

4.4

kL/year8.0

t-CO2/year

Ⅱ Energy Audit of Factories andResults

2. Improvement measure

Ⅲ Energy Conservation
Improvement Proposals

A setting criterion of –25°C has been specified for a certain freezer where frozen foods are stored, but it is actuallyoperated at –28°C, well below the criterion. At lower temperatures, more energy is consumed to generate the cold heat.

Ⅰ Significance and Procedures ofEnergy Conservation

1. Current problem③ x \19/year③ x 9.97 GJ/1,000 kWh x 0.0258 kL/GJ③ x 0.470 t-CO2/1,000 kWh(* For a CO2 emission factor, use the one provided by your contracted power company.)

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17

Case B-2: Replacing the Air-cooled Chiller with the Heat-Cold Simultaneous Feed Heat Pump
1. Current problem

Brine
-5°C

A certain noodle-making factory heats noodles in a 98°C
boiling tank heated by a boiler and cools them in 2°C cold
water in the next process. Cold water is produced by an ice
heat storage system based on an air-cooled chiller, but thechiller has aged and the waste heat is not utilized.

Well water 18°C

Ice heatstorage

Air-cooled
chiller
0°C

Heat
exchanger

Boiler(Steam)Boilingtank 98°C

Coolingtank 2°C

2°C
Well water 18°C

Fig.
Current flow
図 11 現状のフロー

2. Improvement measure
Well water
18°C

Replace the aged chiller with a heat pump capable ofsimultaneously feeding the heat and cold (HP in Fig. 2) andinstall a new hot water storage tank. Conventionally, 18°C
well water has been directly heated by boiler steam. After
improvement, however, feed water is heated to 60°C by therecovery heat from cold water production to reduce theboiler's load.

Hot water
storage
tank

Brine
-5°C

60°C

New

Ice heatstorage

HP
65°C

0°C

Replaced

60°C

Boiler(Steam)Boilingtank 98°C

Heat
exchanger

Coolingtank 2°C

2°C
Well water 18°C

3. Effect estimation

Fig. 2 Improved flow

(1) Calculation formulaPower consumption: Cooling heat quantity (GJ/year) / Cooling COP / 0.0036 (GJ/kWh)
HP heating volume: Cooling heat quantity (GJ/year) / Cooling COP x Heating COP
Boiler heating heat quantity (improved): Heating heat quantity (GJ/year) – HP heating volume (GJ/year)
Fuel consumption (improved): Boiler heating heat quantity (GJ/year) / Boiler efficiency / Lower heating value offuel (GJ/1,000 m3)(2) Prerequisites for calculation
Specific heat of water: 4.2 MJ/(t･K)
Water temperature: Well water 18°C
Cold water (2°C) volume: 6 t/h x 5 h/day x 300 days/year = 9,000 t/year
Cooling heat quantity: 9,000 t/year x (18°C – 2°C) x 4.2 MJ/t･K = 605 GJ/year
Hot water (98°C) volume: 3 t/h x 5 h/day x 300 days/year = 4,500 t/year
Heating heat quantity: 4,500 t/h x (98°C – 18°C) x 4.2 MJ/t･K = 1,512 GJ/year
Current heat source: Air-cooled chiller (COP 1.6), boiler (efficiency 85%)
Heating value of fuel (City gas 13A): Lower 40.5 GJ/1,000 m3
Improved heat source: Heat pump (heating COP = 2.75, cooling COP = 1.75)* It is assumed that there was no other increase or decrease in heat storage losses, pump power, etc.

Table 1 Status quo
Cold water

Hot water

Item

Cold water

Hot water

Required heat quantity (GJ/year)

605

1,512

Required heat quantity (GJ/year)

605

1,512

Input

Cooling

Boiler

378

605

1,512

Air-cooled chiller(GJ/year)

COP

18

Table 2 Post-improvement status

Item

1.00

1.60

HP
(GJ/year)

Input
346

COP

1.00

CoolingHeating

Boiler

605

952

560

1.75

2.75

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4. Effects
kWh/year

43.9 1,000 m3/year
96,000kWh/year④ Fuel consumption (improved)

16.3 1,000 m3/year⑤ Reduced power consumption

9,000⑥ Reduced fuel consumption

kWh/year①−③
27.6 1,000 m3/year ②−④⑦ Energy conservation rate43

⑧ Saved amount of money

2,986⑨ Reduction in crude oil equivalent⑩

CO2 reduction%

Calculated in crude oil equivalent\1,000/year⑤ x \19/kWh + ⑥ x \102/m3

34.3

kL/yearCalculation formula omitted

65.9

t-CO2/year

Calculation formula omitted[Reference] Heat pump system and COP

Fig. 3 shows a configuration of the heat pump system. A substance called a refrigerant circulates in the heat pumpthrough a compressor, heat exchanger (condensation), expansion valve, heat exchanger (evaporation) and compressor inthat order. When the refrigerant is compressed, it is turned from a gas into a liquid while emitting the heat (condensation),
and when it is expanded, it is turned into the gas while absorbing the heat (evaporation). Thus, the refrigerant circulates
while repeating compression and expansion (condensation and evaporation), thereby pumping up the heat from thelow-temperature side to the high-temperature side.
On the cooling process side in Fig. 3, brine (antifreeze liquid like ethylene glycol solution) leaving the heat pump system at–5°C cools an object in the cooling process and returns to the heat pump system at 0°C. Because it leaves at –5°C andreturns at 0°C, the heat Q1 moves from the cooling process to the heat pump system.
On the heating process side, the hot water returning from the process at 60°C is heated to 65°C and returned to theprocess. On this side, the heat Q2 moves from the heat pump system to the process.
A drive force to compress and circulate the refrigerant is input to the heat pump system as an external task L (motor drive
power).

Configuration ofheat pump system

Compressor

Motor

Brine
-5°C

60°C
Heating
process

Cooling
process

Condensation Evaporation

65°C
Heat
exchanger

Expansionvalve

Ⅰ Significance and Procedures ofEnergy Conservation③ Power consumption (improved)

105,000

Ⅱ Energy Audit of Factories andResults② Fuel consumption (current)

Heatexchanger

0°C

Ⅲ Energy Conservation
Improvement Proposals① Power consumption (current)

Fig. 3 Conceptual diagram of heat pump
Q1/L is referred to as a cooling COP (Coefficient of Performance) and Q2/L as a heating COP. Because more heat is
moved with respect to input as a COP value becomes higher, it means that the heat pump system has high performance.
L (kJ/h) is converted to electric power according to the formula, W (kW) = L (kJ/h) x 3,600*.
* The unit of power consumption and that of cooling/heating capacity are both kW in the specifications, etc. Care should be taken not to
confuse them.

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19

C. Pumps, Fans, Compressors, etc.
Case C-1: Inverter-based Flushing Pumps
1. Current problem

Pump head (m)The degreasing and flushing processes of
the coating facilities have flushing pumps forshower washing of products. Currently, a flowrate is controlled with a valve and pressure
losses due to the valve result in power
losses.

I: Resistance curvewhen controlled withthe valve
II: Resistance curvewhen the valve isfully opened
A: Current performance
curve
B: Performance curveafter installation of
the inverter

2. Improvement measure
Install an inverter for the flushing pump andopen the valve fully to control the flow rate by
motor rotating speed. This will reduce power
consumption of the pump.

Flow rate (m3/h)

Fig. 1 Pump characteristic curve

3. Effect estimation(1) Calculation formula
Current power consumption: Current power consumption of pump motor (kW) x Operating time (h/year)
Improved power consumption: Current power consumption (kW) x Ratio of current power to improved power / Inverter
efficiency(2) Prerequisites for calculation
Power consumption of pump motor (current): 14.3 kW
Operating time: 20 h/day x 250 days/year = 5,000 h/year
Total pump head: Currently 38 m, After improvement 30 m (The flow rate remains unchanged before and after
installation of the inverter, but the total pump head is lowered by the pressure losses of the valve.)
Actual pump head (shower pressure): 20 m
Ratio of current power to improved power: 0.79
Inverter efficiency: 0.95

4. Effects① Power consumption (current)

71,500kWh/year② Power consumption (improved)

59,500kWh/year③ Reduced power consumption

12,000kWh/year①−②③/①④ Energy conservation rate17%

⑤ Saved amount of money

228\1,000/year⑥ Reduction in crude oil equivalent

3.1

kL/year

5.6

t-CO2/year⑦

CO2 reduction*③ x \19/kWh③ x 9.97 GJ/1,000 kWh x 0.0258 kL/GJ③ x 0.470 t-CO2/1,000 kWh(* For the CO2 emission factor, use the one provided by your contracted power company.)

20

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5. Implementation of the proposal and tuning
In implementing the proposal, measure the current flow rate,pressure (pump head), power consumption, etc. to examine energy
conservation effects thoroughly. After installing the inverter, control
the rotating speed to a conventional cooling water rate andmeasure the actual results of energy conservation effects.

Full valve
opening(100%)

Pressure P (kPa)

70% rotating
speed (Rotating
speed control)

Destinationof useRequiredpressure
for
destinationof usePressure

Pressure at each point (after adjustment)

Fig. 2 Concept of inverter frequency control
Clamp type wattmeter

Data logger

Current clamp
Transmitter

Cock

Heat-retaining
material

Piping Heat-retaining
material

Voltage clip

PipingElectric motor or chiller

Fig. 3 Main measuring instruments(Source: Newly published Energy Conservation Tuning Manual, The Energy Conservation Center, Japan)(3) Tuning procedure①Preparation (understanding of the status quo)・Check and record the current operating condition through measurement. To make it double sure, record the valve
opening so as to restore the status quo.
・Check the current operating level on the pump performance curve.
②Implementation
・Start operation under the current operating requirements (control the flow rate with a regulating valve and ensure
100% rotating speed of the pump).
・Checking that there is no abnormality with the pump current, etc., open the regulating valve gradually and lower therotating speed of the pump to adjust to the conventional flow rate.
・After fully opening the regulating valve, check that the flow rate, pressure (pump head), current (electric power), etc.
are compatible with the characteristics of the pump performance curve.
・Changing the rotating speed within the possible range, measuring the flow rate, pressure and pump electric energy,
and organizing them in a graph, etc. will be useful for future operation.
・By forecasting the rotating speed and pump electric energy for each operating condition throughout the year, it ispossible to calculate reduced electric energy when the pump is controlled by the inverter.

Ⅲ Energy Conservation
Improvement Proposals

Receiver

Ⅰ Significance and Procedures ofEnergy Conservation

Flow rate
Q (m3/h)

Ⅱ Energy Audit of Factories andResults

Pressure gauge

Requiredpressure
for
destinationof usePressure at each point (before adjustment)

Pressure measuring
instrument
Pressuretransmitter

Destinationof usePressure(2) Measurement items (See Fig. 3.)①When a flowmeter is not installed, install an external ultrasonicflowmeter, etc. which is not accompanied by facility
remodeling.
②Utilize an existing pressure gauge for the pressure (pumphead). When continuous measurement is required, remove andreinstall the existing pressure gauge.
③Use a pump current and power for monitoring a pumpovercurrent and checking an energy conservation volume.
There is also a clamp type wattmeter which measures a
voltage with a clip.

Display

Pressure P (kPa)

100% rotating speed(Commercial
operation)(1) Tuning point
Change flow rate control from adjustment by valve opening to
inverter-based control of pump rotating speed. Gradually opening
the valve, lower the pump rotating speed by the inverter. Checking
that there is no abnormality, fully open the valve at the end. (SeeFig. 2.)Ultrasonic flowmeter

50% valve
opening

Flow rate
Q (m3/h)

The following page introduces an explanatory video of the detailed procedure.
https://www.shindan-net.jp/movie_ch/

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21

Case C-2: Inverter-based Scrubber Fan
1. Current problem
An exhaust scrubber in a factory has an airflow rate adjusted with a damper, having power losses corresponding to thepressure losses of the damper. The airflow rate is constant throughout the year, but it can be lowered on holidays because
there is less generation of odor.

2. Improvement measure
Install an inverter for a scrubber fan and adjust the airflow rate by changing the motor rotating speed instead of using thedamper. On holidays, lower the airflow rate to reduce power consumption of the fan.

olled

ontr

er-c

Power ratio (%)

p
Dam

Holiday

c

er-

ert

Inv

Operating day

ed

oll

tr
on

Airflow ratio (%)

Fig. 1 Airflow ratio and power ratio of fan

3. Effect estimation(1) Calculation formula
Current power consumption: Fan motor capacity (kW) x Motor load factor (%) x Power ratio (current) x Operatingtime (h/year)
Improved power consumption: Power consumption (current) x Ratio of current power to improved power / Inverter
efficiency(2) Prerequisites for calculation
Fan motor capacity: 37 kW
Motor load factor 90%
Air feed ratio: Currently 90%, After improvement 90% on operating days and 45% on holidays
Power ratio: Currently 98.7%, After improvement 72.9% on operating days and 9.1% on holidays
Motor run time: Currently 8,760 h/year, After improvement 6,000 h/year on operating days and 2,760 h/year on
holidays
Inverter efficiency: 0.95
Ratio of current power to improved power: 0.535 = (6,000 x 0.729 + 2,760 x 0.091) / (8,760 x 0.987)

4. Effects① Power consumption (current)

287,900

kWh/year② Power consumption (improved)

162,100

kWh/year③ Reduced power consumption

125,800

kWh/year①−②④ Energy conservation rate

44

%

③/①

⑤ Saved amount of money

2,390\1,000/year⑥ Reduction in crude oil equivalent

32.4

kL/year⑦ CO2 reduction*

59.1

t-CO2/year③ x \19/kWh③ x 9.97 GJ/1,000 kWh x 0.0258 kL/GJ③ x 0.470 t-CO2/1,000 kWh(* For the CO2 emission factor, use the one provided by your contracted power company.)

22

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Case C-3: Preventing the Leak from the Air Piping
1. Current problem* A ratio of an air outflow rate by leak to an air feed rate to the air piping(1) Simple leak rate estimation method
A leak rate can be obtained by the following method.
①When factory operation is suspended, close all the valves on the part of the facility using the compressed air and start
the compressor to boost the air pressure in the piping (Figs. 1 and 2).
②Preset P1 and P2 (P1 > P2) in the vicinity of the normal pressure and measure the time t1 required for P2 to turn to P1 at
the time of boosting the pressure.
③Stop the compressor (or close the main compressor valve) and measure the time t2 required for P1 to turn to P2 at thelater time of stepping down the pressure.
④Based on t1 and t2, the leak rate is expressed by the following formula.
Leak rate = t1 / (t1 + t2)

Slow
declineElapsed time

Fig. 1 Air piping leak check chart(Normal time, with low leak amount)

Pressure

Pressure

In case the leak is low (Fig. 1), the piping pressure drops slowly, extending t2 (if the leak is zero, t2 becomes ∞). In casethe leak is high (Fig. 2), on the other hand, the pressure drops rapidly, shortening t2. The leak rate differs from one system
to another, depending on the piping length, number of branches, number of valves, etc. Manage the leak rate, and if its
value increases, find a leak spot and take a measure.

Rapid
declineElapsed time

Ⅱ Energy Audit of Factories andResults

Reduce compressor power by identifying a leak spot of the air piping which feeds the compressed air from the compressor
to the facility using compressed air, and taking a leak preventive measure. In addition to a daily sequence of finding a leakbased on air leak sound to repairing the leak, manage a leak rate* regularly; once it increases, find individual leak spots
and take a measure.

Ⅲ Energy Conservation
Improvement Proposals

2. Improvement measure

Ⅰ Significance and Procedures ofEnergy Conservation

A leak from the air piping is repaired at the time of daily inspection, but not measured quantitatively. The piping used for along period has many leaks, resulting in a higher airflow rate of the compressor.

Fig. 1 Air piping leak check chart(With high leak amount)(2) Detection of a leak spot
Prior to detecting a leak spot, prepare an air piping system diagram so that you can see a piping system and connected
equipment at a glance (Fig. 3). Find the leak spot along the air piping. Easily leaking spots include a piping joint, valve,rubber hose joint, solenoid valve, etc. To detect the leak spot, there is a method to use a leak detector designed to detect
an ultrasonic wave generated at an air leak spot, in addition to simply relying on your ears. Some detectors are capable ofobtaining a rough leak rate at each part besed on the signal strength.

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23

ReceivertankUltrasonic leakdetector
Compressor

Factory facilities

Fig. 3 Measurement of compressed air leak

3. Effect estimation(1) Calculation formula
Current power consumption: Compressor motor capacity (kW) x Motor load factor (%) x Operating time (h/year)
Improved power consumption: Power consumption (current) x Ratio of current power to improved power(2) Prerequisites for calculation
Compressor motor capacity: 37 kW (inverter-controlled)
Motor load factor: 80%
Operating time: 20 h/day x 300 days/year = 6,000 h/year
Leak rate (current): 20% (measurement result)
Leak rate (improved): 4% (If the number of leaks is reduced to prevent 80% of them, the improved leak rate is 20% x(1 – 0.8) = 4%.)
Ratio of current airflow rate to improved one: 0.84 (Fewer leaks reduce the airflow rate of the compressor.)
Ratio of current power to improved power: 0.84 (The inverter-controlled compressor controls the airflow rate with therotating speed, and the ratio of airflow rate and power is almost same.)

4. Effects① Power consumption (current)

177,600

kWh/year② Power consumption (improved)

149,200

kWh/year③ Reduced power consumption

28,400kWh/year①−②③/①④ Energy conservation rate

16%

⑤ Saved amount of money

540\1,000/year⑥ Reduction in crude oil equivalent

7.3

kL/year⑦ CO2 reduction*

13.3

t-CO2/year③ x \19/kWh③ x 9.97 GJ/1,000 kWh x 0.0258 kL/GJ③ x 0.470 t-CO2/1,000 kWh

The following page introduces an explanatory video of the detailed procedure.
https://www.shindan-net.jp/movie_ch/

24

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Case C-4: Reducing the Compressor Discharge Pressure
1. Current problem

3. Effect estimation(1) Calculation formula
Current power consumption: Compressor motor capacity (kW) x Motor load factor (%) x Operating time (h/year)
Improved power consumption: Power consumption (current) x Ratio of current power to improved power(2) Prerequisites for calculation
Compressor motor capacity: 74 kW (37 kW x 2 units)
Motor load factor: 80%
Operating time: 20 h/day x 250 days/year = 5,000 h/year
Discharge pressure: Currently 0.7 MPa → After improvement 0.6 MPa
Ratio of current power to improved power: 0.92 = (93 / 101) See Fig. 1.

Power ratio (%)[Requirements]
Suction air temperature

20℃

Suction air humidity

60％

Suction pressure-50mmAq.

Compression stages

1 stage

Flow rate

Constant

Discharge pressure (MPa)Fig. 1 Compressor discharge pressure vs. power consumption (theoretical values)

Ⅱ Energy Audit of Factories andResults

Because the discharge pressure is higher than the required pressure, lower the former from 0.7 MPa to 0.6 MPa.

[Note] Lowering the discharge pressure is effective to the positive displacement compressors such as reciprocating and screw
compressors.

Ⅲ Energy Conservation
Improvement Proposals

2. Improvement measure

Ⅰ Significance and Procedures ofEnergy Conservation

A compressor has been installed as a common air pressure source for the factory and the pressure is regulated by areducing valve for use. The compressor consumes more electric power as the discharge pressure increases.

4. Effects① Power consumption (current)

296,000

kWh/year② Power consumption (improved)

272,300

kWh/year③ Reduced power consumption

23,700kWh/year①−②④ Energy conservation rate

③/①

8

%

Saved amount of money

450\1,000/year⑥ Reduction in crude oil equivalent

6.1

kL/year11.1

t-CO2/year⑤⑦

CO2 reduction*③ x \19/kWh③ x 9.97 GJ/1,000 kWh x 0.0258 kL/GJ③ x 0.470 t-CO2/1,000 kWh(* For the CO2 emission factor, use the one provided by your contracted power company.)

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25

5. Implementation of the proposal and tuning
To reduce the discharge pressure, there are measures on the part of using the compressed air (reducing and optimizing therequired pressure of each equipment, reducing the piping resistance, preventing a leak, and so on), but the following
describes a method for regulating the discharge side while monitoring the end pressure.
(1) Tuning points
Measure the discharge pressure and flow rate of thecompressor, and the end pressure of the piping, andcheck whether the discharge pressure can belowered. If the consumption of the compressed air
fluctuates, consider with the data at the highest
consumption. When the destination of use isdiversified and the timing is unknown, it isnecessary to continuously measure and record.

Dryer
Compressor
FilterReceivertank

Reducing
valve

FilterPressure(MPa)

Margin ofpressure
losses(2) Measurement items▪ Pressure (compressor discharge pressure, endpressure of the piping)Measurement is imperative. If a pressure gauge is
not available, find a spot such as a drain port or apurge line, where the pressure can be extracted.
▪ Electric power
A clamp type wattmeter, etc. is convenient, which
combines a clamp ammeter and voltage measurement with a clip. An airflow rate can be estimatedfrom an electric power value, using the characteristic curve of the compressor. When multiple
compressors are used, record individual electric
powers.

Pressure at each point (unregulated)

Requiredpressure fordestination of
use PdPressure(MPa)

Requiredpressure fordestination of
use PdPressure at each point (regulated)

Fig. 2 Reduction of compressor discharge pressure(3) Tuning procedure①Preparation (understanding of the status quo)
▪ Prepare an air piping system diagram to check and record the current valve (reducing valve) opening, etc.
▪ Continue measurement during a pressure fluctuation period in order to grasp the pressure fluctuations of the compressor.
▪ When the working pressure fluctuates from one product to another, make measurement during the maximum working
pressure period.
▪ Record the production requirements such as a type of product and a production volume.
▪ Based on the trends of pressure and flow rate, check a difference between the discharge pressure and the end pressure,a margin and stability for the required pressure, pressure fluctuations at the time of a sharp increase of the flow rate, andso on to determine the reduction range of the discharge pressure.
▪ When there is a large difference between the discharge pressure and the end pressure, and it is throttled with the reducing
valve, there is a potential to lower the discharge pressure, which corresponds to a margin of pressure regulation with the
reducing valve.
▪ When there is a large pressure difference without much throttling with the reducing valve, it is likely that the piping size issmall in comparison with the flow rate, or that the inside of the piping has been contaminated more.
▪ By forecasting the discharge pressure and compressor’s electric energy for each operating condition throughout the year,
it is possible to forecast reduced electric energy when the compressor discharge pressure is lowered.
②Implementation▪ Lower the discharge pressure in two steps or so, not at once. When this is done, regulate the reducing valve as well.
▪ Patrol periodically to check for any abnormality during implementation of tuning.
The following page introduces an explanatory video of the detailed procedure.
https://www.shindan-net.jp/movie_ch/

26

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Case C-5: Replacing the Compressor with the Roots Blower
1. Current problem
The aeration air of a drainage treatment tank (required pressure of about 60 kPa (0.06 MPa)) is fed by the compressor(discharge pressure of 0.69 MPa), wasting pressurization energy.

Aeration airflow rate
Reducing
valve

Replace the compressor with a roots blower because thepressure of about 60 kPa required for aeration is obtained fromthe roots blower. It is operable at lower power because thedischarge pressure is low. Use a pulley or an inverter to regulate
an airflow rate of the roots blower.

* Airflow rate in the standard suction
condition (20°C, absolute pressure =101.3 kPa, relative humidity = 65%)

3. Effect estimation

Fig. 1 Current operating condition of aeration tank(2) Prerequisites for calculation
Compressor: 30 kW, 0.69 MPa, 5.9 m3/min
Current aeration tank inlet pressure: 60 kPa
Aeration airflow rate: 3.9 m3/min
Compressor airflow ratio: 3.9 m3/min / 5.9 m3 = 66.1%
Compressor power ratio: 90% (See Fig. 2.)
Roots blower motor capacity: 11 kW
Roots blower rated pressure: 60 kPa
Roots blower rated flow rate: 6.1 m3/min
Operating time: 8,760 h/year

Power ratio (%)(1) Calculation formula
Current power consumption: Compressor motor capacity (kW) x Power ratio x Operating time (h/year)
Improved power consumption: Roots blower motor capacity (kW) x Aeration airflow rate (m3/min) / Rated flow rate
(m3/min) x Operating time (h/year)

Airflow ratio (%)

Fig. 2 Compressor (suction throttle control)
power ratio

4. Effects① Power consumption (current)

236,500

kWh/year② Power consumption (improved)

61,600kWh/year③ Reduced power consumption

174,900

kWh/year①−②④ Energy conservation rate

74

%

③/①

⑤ Saved amount of money

3,323\1,000/year⑥ Reduction in crude oil equivalent

45.0

kL/year⑦ CO2 reduction*

82.2

t-CO2/year

Ⅱ Energy Audit of Factories andResults

Compressor

Ⅲ Energy Conservation
Improvement Proposals

2. Improvement measure

Ⅰ Significance and Procedures ofEnergy Conservation

Pressure gauge③ x \19/kWh③ x 9.97 GJ/1,000 kWh x 0.0258 kL/GJ③ x 0.470 t-CO2/1,000 kWh(* For the CO2 emission factor, use the one provided by your contracted power company.)

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27

Case C-6: Pulsed Air Blow
1. Current problem
Company A, a plastic products manufacturer, continuously blows the air to remove plastic refuse, but the compressor
power has been increasing.

2. Improvement measure

Flow rate (ℓ/min)

Change an on-going continuous blow to a pulsed blow. A compressor airflow rate can be lowered by 50% without affecting
a blow effect. Some pulsing equipment is opened and closed by only air feed to generate a pulsed blow without requiring
the power supply.
Pulsed blows

Continuous blow

Reduced parts by pulsing

Time

Fig. 1 Continuous blow vs. pulsed blow

(Source: FY2012 Successful Cases of Energy Conservation Grand Prize)

3. Effect estimation(1) Calculation formula
Current power consumption: Unimproved nozzle blow rate (m3/h/nozzle) x No. of nozzles x Blow time (h/year) x
Rated compressor specific power (kW/m3/h)
Improved power consumption: Power consumption (current) x Compressor power ratio (%)(2) Prerequisites for calculation
Unimproved nozzle blow rate: 12 m3/h/nozzle (200 ℓ/(min▪ nozzle))
No. of nozzles: 5Compressor specific power: 0.164 kW/m3/h (9.8 kW/m3/min)Compressor power ratio: 85% (at 50% lower airflow rate by suction throttle control)
Annual blow time: 10 h/day x 360 days/year = 3,600 h/year

4. Effects① Power consumption (current)

35,400kWh/year② Power consumption (improved)

30,100kWh/year③ Reduced power consumption

5,300

kWh/year①−②④ Energy conservation rate

15

%

③/①

⑤

Saved amount of money101\1,000/year⑥ Reduction in crude oil equivalent

1.4

kL/year2.5

t-CO2/year⑦

CO2 reduction*③ x \19/kWh③ x 9.97 GJ/1,000 kWh x 0.0258 kL/GJ③ x 0.470 t-CO2/1,000 kWh(* For the CO2 emission factor, use the one provided by your contracted power company.)

28

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D. Boilers, Industrial Furnaces, etc.
Case D-1: Thermal Insulation for the Steam Valve

Dissipated heat (W/m)

Attach a detachable thermal insulation jacket to the bare steam valve to prevent heat dissipation and save energy.

Steam temperature (°C)

Fig. 1 Dissipated heat from bare steam piping(Calculation requirements: Horizontal pipe, natural convection, ambient
temperature = 20°C, emissivity ε = 0.7)

Fig. 2 Example of thermal insulation of
steam header valve

3. Effect estimation(1) Calculation formula
Reduction of heat losses by thermal insulation: Σ {Valve length equivalent to straight pipe (m/pc.) x Dissipated heatfrom bare steam pipe (W/m) x No. of valves} x Thermal insulation efficiency (%) x Operating time (h/year)
Fuel reduction: Reduction of heat losses by thermal insulation / Lower heating value of fuel / Boiler efficiency (%)

Table 1 Dissipated heat of piping
Name

Size

Qty.

Lengthequivalent tostraight
pipe(Note 1)(pcs.)(m/valve)

Dissipatedheat/m(Note 2)(W/m)(MJ/m･h)Flange typeglobe valve
10 kg/cm2

Dissipatedheat(MJ/h)

Note 1: Datasheet for energy
management (The Energy
Conservation Center,
Japan)
Note 2: See Fig. 1 for the dissipatedheat/m.

Ⅱ Energy Audit of Factories andResults

2. Improvement measure

Ⅲ Energy Conservation
Improvement Proposals

The steam valve of a steam header in a boiler room is not provided with thermal insulation, resulting in useless heatdissipation.

Ⅰ Significance and Procedures ofEnergy Conservation

1. Current problem

Total(2) Prerequisites for calculation
Steam pressure and temperature (saturation): 0.5 MPa-G, 159°C
Thermal insulation efficiency: 89%
Boiler efficiency: 85%
Operating time: 2,400 h/year
Lower heating value of fuel: 40.5 MJ/m3 (City gas 13A)

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29

4. Effects①

Reduced fuel consumption

4,100

②

Energy conservation rate

-

%

③

Saved amount of money

418\1,000/year④

Reduction in crude oil equivalent

4.7

kL/year⑤

CO2 reduction

9.2

t-CO2/year

m3/year① x \102/m3① x 44.8 MJ/m3 x 0.0258 kL/GJ① x 44.8 MJ/m3 x 0.0136 x (44 / 12) t-CO2/GJ

5. Thermal images (infrared thermography)
Fig. 3 and Fig. 4 show the examples of thermal images of the bare steam piping around the boiler. Some non-contact
radiation thermometers digitally measure the spot temperature. To find a high-temperature area, there are thosecapable of measuring in the form of image.

<Examples of thermal images of bare steam piping>

Fig. 3 Side flange area of boiler

Fig. 4 Steam trap

30

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Case D-2: Replacing the Boiler for Higher Efficiency
1. Current problem
The current heavy oil-fired water tube boiler is inefficient. It was installed more than 30 years ago and has greatly aged.

3. Effect estimation(1) Calculation formula
Boiler output: Current fuel consumption (kL/year) x Lower heating value of heavy oil A x Current boiler efficiency
Improved fuel consumption: Boiler output (GJ/year) / Lower heating value of city gas 13A (GJ/1,000 m3) / Renewedboiler efficiency(2) Prerequisites for calculation
Current fuel consumption: 600 kL/year (heavy oil A)
Fuel heating value (lower): 37.1 GJ/kL (heavy oil A), 40.5 GJ/1,000 m3 (city gas 13A)
Boiler efficiency (average): 80% (current), 93% (renewed)

4. Effects②

600kL/yearHeavy oil A

1,000 m3/year City gas 13A

Fuel consumption (improved)

470③ Energy conservation rate

9.8%

Crude oil equivalent basis④ Saved amount of money

2,460\1,000/year① x \84/L – ② x \102/m3⑤ Reduction in crude oil equivalent

62.0

kL/year⑥ CO2 reduction

575.8

t-CO2/year(① x 39.1 GJ/kL – ② x 44.8 GJ/1,000 m3) x 0.0258 kL/GJ(① x 39.1 GJ/kL x 0.0189 – ② x 44.8 GJ/1,000 m3 x 0.0136) x (44 / 12)
t-CO2/GJ[Reference] Small once-through boiler
After feed water pressurized by a pump is preheated as shownin Fig. 1, it is heated, evaporated and overheated in a generatingAir
tube, flows into a steam-water separator, and is separated into
steam and water. A start-up time is short because of a structure
Exhaust gas
retaining less water, and followability to load fluctuations has
been enhanced by advanced control.
Feed water
Small once-through boilers, which are provided with an economizer preheating feed water with exhaust gas, have highefficiency, and some gas-fired boilers, which particularly have
Combustion
almost no sulfur content in their fuel, recover the waste heat until
Preheating gasof feedthe exhaust gas temperature drops below a dew point andwater
exceed 98% in terms of rated efficiency.
An evaporation volume is about 2 to 3 t/h. Multiple units of them
are installed to substitute for a large boiler.

Fuel

Steam

Ⅲ Energy Conservation
Improvement Proposals① Fuel consumption (current)

Ⅱ Energy Audit of Factories andResults

Considering a deteriorated heavy oil tank and piping, switch a fuel to city gas and introduce a small once-through boiler.
Also, the facilities with a remote monitoring function are capable of always monitoring the operational status of the boiler toalarm at the time of an error, and browse and manage boiler operation data via the Internet network by the IoT technology.

Ⅰ Significance and Procedures ofEnergy Conservation

2. Improvement measure

Steamwater
separator

Generating
tubes

Fig. 1 Small once-through boiler

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31

Case D-3: Recovering the Steam Drain
1. Current problem
Drain discharged from a mold steam heater is supposed to be returned into a tank via the piping, but its heat is notrecovered because impurities flowing out of the heater accumulate in the tank.

2. Improvement measure

Fuel reduction rate
(For 20°C feed water)

Clean inside the drain tank and the mold in order to remove the impact of the impurities, coat inside the tank to prevent
rust, and utilize the drain as make-up water for boiler feed water.

Feed water temperature (°C)

Fig. 1 Feed water temperature and fuel reduction rate

3. Effect estimation(1) Calculation formula
Drain recovery rate (ratio to feed water volume) ηd : Drain recovery volume (t/year) / Boiler feed water volume (t/year)
Water feed temperature after drain recovery: Original feed water temperature (°C) + ηd x (Drain temperature – Original
feed water temperature) (°C)
Fuel reduction: Current fuel consumption (kL/year) x Fuel reduction rate after drain recovery (%)(2) Prerequisites for calculation
Current fuel consumption: Heavy oil A, 340 kL/year
Evaporation volume: 340 kL/year x 10.9 kg/L = 3,706 t/year (evaporation ratio: 10.9 kg/L)
Boiler feed water: 3,706 t/year x 1.08 = 4,002 t/year (blow rate: 8%), Temperature: 20°C
Drain recovery rate: 50%
Drain recovery volume: 3,706 t/year x 0.5 = 1,853 t/year, Recovery temperature: 90°C
Drain recovery rate (ratio to feed water volume) ηd : 1,853 t/year / 4,002 t/year = 0.463
Feed water temperature after drain recovery: 20°C + 0.463 x (90°C – 20°C) = 52°C
Fuel reduction rate after drain recovery: 5.0% (See Fig. 1)

4. Effects① Fuel consumption (current)

340

kL/year② Reduced fuel consumption

17

kL/year③ Energy conservation rate

5%

④ Saved amount of money*

2,873⑤ Reduction in crude oil equivalent

17.1⑥ CO2 reduction

kL/year46.1

t-CO2/year

See Fig. 1.

\1,000/year② x \84/L + 1,853,000 L/year x Unit price of tap water: \780/1,000 L② x 39.1 GJ/kL x 0.0258 kL/GJ② x 39.1 GJ/kL x 0.0189 x (44 / 12) t-CO2/GJ(* The saved amount of money includes the reduction effect of the feed water volume.)

32

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Case D-4: Improvement of Combustion Air Ratios of Industrial Furnaces
1. Current problem

Strengthen combustion control to adjust the air ratio to an appropriate value and enhance energy conservation.

Fuel reduction rate (%)

Oxygenconcentration

Exhaust gas oxygen concentration (%)<Reading the graph>
The current exhaust gas has 9.8% oxygen
concentration and its temperature is
400°C.
① Read the air ratio 1.8 on the horizontal

axis of the graph from the exhaust gas
oxygen concentration 9.8% on the rightaxis of the graph.

② Read the fuel reduction rate 10% on theleft axis of the graph corresponding to
the air ratio 1.2 in the fuel reduction rate
curve of the exhaust gas temperature
400°C, which starts from the air ratio 1.8
on the horizontal axis of the graph.

Air ratio

Ⅱ Energy Audit of Factories andResults

2. Improvement measure

Ⅰ Significance and Procedures ofEnergy Conservation

A steel heating furnace uses a city gas as a fuel. Currently, the air ratio is excessive (high oxygen concentration in an
exhaust gas) and an exhaust gas volume increases, resulting in large energy losses.

Fig. 1 Air ratio reduction effect (13A city gas)

(1) Calculation formula
Fuel reduction = Current fuel consumption (m3/year) x Fuel reduction rate (%)(2) Prerequisites for calculation
Current fuel consumption: City gas 50,000 m3/year
Exhaust gas oxygen concentration: Currently 9.8% (air ratio 1.8), After improvement 3.7% (air ratio 1.2)
according to Fig. 1, Exhaust gas temperature 400°C
Fuel reduction rate: 10% according to Fig. 1

Ⅲ Energy Conservation
Improvement Proposals

3. Effect estimation

4. Effects① Fuel consumption (current)

50,000m3/year② Reduced fuel consumption

5,000

m3/year③ Energy conservation rate

10%

See Fig. 1.

④ Saved amount of money

510\1,000/year② x \102/m3⑤ Reduction in crude oil equivalent

5.8

kL/year⑥ CO2 reduction

11.2

t-CO2/year② x 44.8 GJ/1,000 m3 x 0.0258 kL/GJ② x 44.8 GJ/1,000 m3 x 0.0136 x (44 / 12) t-CO2/GJ

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33

5. Implementation of the proposal and tuning(1) EC Guideline of the Energy Conservation Act
The Energy Conservation Act stipulates the standard air ratios as listed in Table 1 as to combustion management of theindustrial furnaces.
Table 1 Standard air ratios on industrial furnaces (excerpts*1)
Category*2

Gaseous fuelLiquid fuelContinuousIntermittent

ContinuousIntermittent

Metal casting melting furnaces

1.25

Continuous steel billet heating furnaces

1.20

1.35

1.30

1.40

−

1.25

−

RemarkMetal heating furnaces other than the above

1.25

1.35

1.25

1.35

Metal heat treatment furnaces

1.20

1.25

1.25

1.30

Oil heating furnaces

1.20

−

1.25

−

Pyrolyzers and reforming furnaces

1.20

−

1.25

−

Cement combustion furnaces

1.30

−

1.30

−

Liquid fuel value in case of pulverized coal-fired type

Lime combustion furnaces

1.30

1.35

1.30

1.35

Liquid fuel value in case of pulverized coal-fired type

Drying furnaces

1.25

1.45

1.30

1.50

Burner combustion part only

*1 Public notice by METI: Excerpted from EC Guideline of Business Operators for Rationalization of Energy Use at Factories, etc., Appendix
Table 1(A), (2). The standard air ratio values in this table set the air ratio measured at the exhaust outlet of the furnace when combusting at
near the rated load after inspection or repair.
*2 See "Remarks" of Appendix Table 1(A) (2) because the following applications may
Recuperator
be excluded.
Fuel・Those with a rated capacity (burner’s fuel combustion performance) of less than
Exhaust gas
Preheat air
20 L/hr. (in crude oil equivalent)components
・Those requiring a specific atmosphere for oxidation or reduction
at furnace
・Those requiring the diluted air for maintaining a heat pattern or uniformizing theoutletHeating(O2, CO)furnace internal temperature
furnace・Those combusting flammable waste
Steel material
And so on(4) Tuning procedure① Measure the exhaust gas oxygen concentration to confirm thecurrent air ratio.
Example: O2 = 9.8% → Air ratio = 1.8② Set an adjustment target value.
Target air ratio = 1.2 (O2 = 3.7%)③ Adjust the air ratio in a phased manner.
Step 1. Air ratio: 1.8 → 1.4 (O2 = 6.3%)
Step 2. Air ratio: 1.4 → 1.2 (O2 = 3.7%)

Fig. 2 Air ratio adjustment of industrial furnace(heating furnace)

Oxygenconcentration

Fig. 3 Example of air ratio adjustment

34

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Exhaust gas oxygen concentration (%)(3) Measurement items① Exhaust gas components at the furnace outlet (oxygen (O2)concentration, CO concentration)② Exhaust gas temperature③ Fuel flow rate
④ Combustion air flow rate (if possible)<Example of the adjustment method>
Automatic: Change the air ratio.
Manual: Fix a fuel flow rate andminimize an air flow rate (adjust a linkmechanism, etc).

Fuel reduction rate (%)(2) Tuning points
Combustion air may be used more than standard values for purposessuch as securing combustion stability. Reduce the air ratio while
confirming exhaust gas oxygen concentration at the furnace outlet. In
order to prevent incomplete combustion, it is particularly important toconfirm that there is no CO. Also, pay heed to the fluctuations of thefurnace internal pressure.

E. Lighting Facilities, Power Leveling Facilities, etc.
Case E-1: Replacing the Mercury Lamps of the Factory Warehouse with the LED Lighting
1. Current problem

Replace the mercury lamps with the high-ceiling LED lighting which has been enhanced on the performance and productlineup these days. The LED consumes less power than the mercury lamp for the same illuminance, allowing lower power
consumption by renewing the facilities.
Table 1 LEDs with equivalent illuminance to mercury lamps
Mercury lamp

LEDPower consumption including stabilizer

Power consumption including the DC
power supply (luminous flux)

250 W（HF250X）

250 + 10 = 260 W

Equivalent to 250 W mercury lamp

78 W（9,300 lm）

400 W（HF400X）

400 + 15 = 415 W

Equivalent to 400 W mercury lamp

117 W（14,000 lm）(Source: Catalog of Company H)

3. Effect estimation(1) Calculation formula
Current power consumption: Σ {Current power consumption (kW/unit) x No. of lighting fixtures (unit) x Lighting time (h/year)}
Improved power consumption: Σ {Improved power consumption (kW/unit) x No. of lighting fixtures (unit) x Lighting time(h/year)}(2) Prerequisites for calculation
Lighting time: 10 h/day x 242 days/year = 2,420 h/year
Current power consumption (mercury lamps), No. of units
Existing 250 W mercury lamp: 260 W/unit including the power consumption of the stabilizer, 100 units
Existing 400 W mercury lamp: 415 W/unit including the power consumption of the stabilizer, 50 units
Improved power consumption (LEDs), No of units
LED equivalent to 250 W mercury lamp: 78 W/unit including the DC power supply, 100 units
LED equivalent to 400 W mercury lamp: 117 W/unit including the DC power supply, 50 units

4. Effects① Power consumption (current)

113,100

kWh/year② Power consumption (improved)

33,000kWh/year③ Reduced power consumption

80,100kWh/year①−②④ Energy conservation rate

71

%

③/①

⑤ Saved amount of money

1,522\1,000/year⑥ Reduction in crude oil equivalent

20.6

kL/year37.6

t-CO2/year⑦

CO2 reduction*

Ⅱ Energy Audit of Factories andResults

2. Improvement measure

Ⅲ Energy Conservation
Improvement Proposals* By adoption of the "Minamata Convention on Mercury", it was banned to manufacture, export or import mercury lamps on Jan.
1, 2021.

Ⅰ Significance and Procedures ofEnergy Conservation

A factory warehouse has a high ceiling and uses old-fashioned mercury lamps*.

③ x \19/kWh③ x 9.97 GJ/1,000 kWh x 0.0258 kL/GJ③ x 0.470 t-CO2/1,000 kWh(* For the CO2 emission factor, use the one provided by your contracted power company.)

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35

Case E-2: Power-saving and Energy Conservation by Demand Monitoring
1. Current problem
The contract demand of a ceramics-related factory A is 170 kW, same as the annual maximum power. Main facilities
are turned on and off at relatively short time intervals of 1 to 2 hours. Because the maximum power is not managed,
however, many facilities are simultaneously operated, boosting the maximum power.

2. Improvement measure
Adjust the operation schedule of the main facilities to lower the maximum power. (See "Concept of the operation scheduleof the facilities".) Set the target values and try not to exceed them. A demand monitor is useful for monitoring the working
power. Set a maximum power reduction target to 10 kW. (See "Concept of the maximum power target value".) Also,
utilization of IoT technology allows remote-control operation such as stopping unnecessary facilities according to alarm
signals, etc. output from the demand monitoring equipment.

Concept of the operation schedule of the facilities
Fig. 1 shows the operating condition and power consumptionof the main facilities A to D. At the times t1 and t2, all thefacilities operate simultaneously, maximizing the total power.
The maximum power can be lowered by starting the facility D
later at t1 and earlier at t2, for example.

Facility B
Power (kW)Concept of the maximum power target value

Facility A

Fig. 2 shows the transition of monthly electric energy andmaximum power. The maximum power is 170 kW in October,but it is not proportional to the electric energy. Their relations
are made more understandable by preparing a scatter diagramof the electric energy and maximum power. The electric energy
is 19,300 kWh in the month with the maximum power of 170
kW, but the maximum power remains at 160 kW in somemonths even when the electric energy exceeds 20,000 kWh.
Based on this graph and other information, set the target value
to 160 kW for the moment.

Maximum
power

Facility D

Total

Time
All the facilities operating

Fig. 1 Operation schedule of facilities(conceptual diagram)Contract
demandElectric energy (kWh)Maximum power, contract demand (kW)Electric
energyFacility C

MonthFig. 2 Transition of electric energy and maximum power

36

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From now on, consider the relations of the production volume and product type with the electric energy and maximum
power in details, and organize the operation schedule of the facilities to focus on more accurate and greater reduction.
When the electric energy and maximum power fluctuate greatly from one season to another due to the effect of air
conditioning, it is necessary to consider them with an emphasis put on the operating condition of the air conditioners.

Fig. 3 Relations between electric energy
and maximum power

4. Effects① Contract demand (current)

170

kW

② Contract demand (improved)

160

kW

③ Reduced contract demand④ Reduction rate

10

kW

5.9

%

⑤ Saved amount of money

153\1,000/year①−②③/①③ x \1,500/kW x (185 – 100) / 100 x 12 months/year[Reference] Demand and electricity charge
A demand refers to maximum demand power (= contract demand) and is directly connected to the "basic charge". The
electric energy meter installed by a power company memorizes average power consumption every 30 minutes tocalculate a monthly maximum value.
An electricity charge consists of a "basic charge", "energy charge" and "renewable energy surcharge". The following table
describes them. To reduce the electricity charge, accordingly, you can understand that it is effective to reduce not only ①energy consumption, but ② contract demand.
Electricity charge =Basic charge

Description

Basic charge ratex
② Contract demandxPower factor discount and extra＋

Energy charge
Energy charge ratex
① Energy consumptionx
Fuel adjustment charge＋

Renewable energy surcharge
Renewable energy surcharge ratex
① Energy consumption

Ⅰ Significance and Procedures ofEnergy Conservation

Electric energy (kWh)Ⅱ Energy Audit of Factories andResults(2) Prerequisites for calculation
Current contract demand: 170 kW
Target contract demand: 160 kW(Reduced power: 10 kW)
Power factor (pf): 100%
Basic charge rate: \1,500/kW･month(Use the basic charge rate of your contracted power company.)

Ⅲ Energy Conservation
Improvement Proposals(1) Calculation formula
Basic charge
Contract demand (kW) x Basic charge rate (yen/kW･month) x(185 – pf) / 100

Maximum power (kW)

3. Effect estimation

In the case of receiving the high-voltage power of less than 500 kW, calculation of the basic charge uses the highest value
among the maximum demand powers (demand values) in that month and past 11 months.

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37

F. Production Processes, etc.
Case F-1: Recovering the Waste Heat of the Powder Coating Drying Furnace
1. Current problem
Hot blast of a powder coating drying furnace (baking) is produced by heating the outside air with burners (fuel: LPG). Partof the exhaust gas is recirculated to promote energy conservation, but the exhaust temperature is about 210°C,
discharging the waste heat into the atmosphere.

2. Improvement measure
Waste heat recovery heat exchanger

Recover the waste heat discharged into theatmosphere and preheat the introduced
outside air from 20°C to 70°C to reduce LPG
consumption.

Outside air

Exhaust fan
ExhaustPowder coating and baking drying furnace

New
Existing

BurnerCirculation fan

Fig. 1 Waste heat recovery flow diagram

3. Effect estimation(1) Calculation formula
Waste heat recovery temperature difference: {Exhaust gas temperature (°C) – Annual average temperature of outsideair (°C)} x Waste heat recovery efficiency (%)
Waste heat recovery heat quantity: Exhaust gas volume (m3/h) x Waste heat recovery temperature difference (°C) x
Average specific heat at constant pressure (kJ/m3･K)}
LPG reduction: Waste heat recovery heat quantity (kJ/h) x Coating drying furnace operating time (h/year) / Lower
heating value (kJ/kg)(2) Prerequisites for calculation
LPG consumption (current): 92,700 kg/year
Exhaust gas requirements (volume, temperature): Exhaust gas volume 3,600 m3/h, Exhaust gas temperature 210°C,
Annual average temperature of outside air 20°C
Waste heat recovery efficiency: 26.3% (if it is a little less than 30%, preheating is possible by at least 50°C)
Average specific heat at constant pressure: 1.304 kJ/m3･K
LPG lower heating value: 47.0 GJ/t
Coating drying furnace operating time: 9 h/day x 258 days/year = 2,322 h/year

4. Effects

38①

LPG consumption (current)

92,700kg/year②

Reduced LPG consumption

11,600kg/year③

Energy conservation rate

13

%

④

Saved amount of money

1,508\1,000/year⑤

Reduction in crude oil equivalent

15.2

kL/year⑥

CO2 reduction

34.8

t-CO2/year②/①② x \130/kg② x 50.8 GJ/t x 0.0258 kL/GJ② x 50.8 GJ/t x 0.0161 x (44 / 12) t-CO2/GJ

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Case F-2: Reducing the Radiation Losses from the Opening of the Casting Melting Furnace
1. Current problem

Newly install an air cylinder-driven cover over the
opening. Close it as much as possible while operating
the furnace, and open it only when necessary fortemperature measurement, and so on. This will prevent
radiant heat losses and shorten a melting time.

Newly installed
cover

Φ500

Air cylinder

Melting
furnace

3. Effect estimation

Fig. 1 Installation of driven cover on melting furnace(1) Calculation formula
Radiant heat from the opening: 3.26A x (T1 – Ta)1.25 + 5.67 ε1 A × {(T1 / 100)4 – (Ta / 100)4} (W)Radiant heat from the furnace cover surface: 3.26A x (T2 – Ta)1.25 + 5.67 ε2 A x {(T2 / 100)4 – (Ta / 100)4} (W)Where; A: Opening area (m2), ε1, ε2: Surface emissivity, T1: Melting temperature (K), T2: Furnace cover temperature (K),
Ta: Ambient temperature (K)Operating time considered heat dissipation: Heat dissipation from the opening (kW) x (14 min/batch, 3 batches/60 min)
Reduced electric energy: Operating time considered heat dissipation (kW) x Ratio of furnace cover closable time (%) x
Operating time (h/year)(2) Prerequisites for calculation
Opening area: A = 0.196 m2, Surface emissivity of the melted casting: ε1 = 0.3, Surface emissivity of the furnace cover:ε2 = 0.75
Melting temperature: T1 = 1,573 K (1,300°C), Furnace cover temperature: T2 = 523 K (250°C), Ambient temperature:
Ta = 288 K (15°C)
Ratio of furnace cover closable time: 12 min of 14-min operating time → 85%
Furnace operating time: 18 h/day x 20 days/month x 12 months/year = 4,320 h/year
Melting furnace efficiency: η = 80%

4. Effects① Heat dissipation from opening

17.7

kW

② Heat dissipation from furnace cover

0.8③ Reduced electric energy④ Energy conservation rate

77,600⑤ Saved amount of money

1,474\1,000/year⑥ Reduction in crude oil equivalent⑦ CO2 reduction*

20.0

kL/year36.5

t-CO2/year–

kW
kWh/year

Ⅱ Energy Audit of Factories andResults

Opening

Ⅲ Energy Conservation
Improvement Proposals

2. Improvement measure

Ⅰ Significance and Procedures ofEnergy Conservation

A furnace cover at the top of a melting furnace is opened for automatic measurement of the melting temperature, allowing
radiant heat losses from this opening during operation hours.

Operating time considered: (14 min/batch x 3 batches/60 min)Operating time considered: (14 min/batch x 3 batches/60 min)(① – ②) x Ratio of furnace cover closable time x Furnace operating time / η%③ x \19/kWh③ x 9.97 GJ/1,000 kWh x 0.0258 kL/GJ③ x 0.470 t-CO2/1,000 kWh(* For the CO2 emission factor, use the one provided by your contracted power company.)

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39

G. Solar Power Generation, etc.
Case G-1: Introducing the Self-consumption Solar Power Generation System
1. Current problem
The rooftop of the facility to be audited has good solar radiation conditions and a vacant space (roof area of about 1,000m2) for installing a photovoltaic array*, but it has not been utilized so far.
* Array: Multiple photovoltaic panels arranged and connected

2. Improvement measure
Assuming that all generated power is self-consumed, the installed capacity of the photovoltaic array shall be 50 kW in viewof the hourly power consumption characteristic (daytime power consumption is 50 kW or more) of the said business
operator.
Photovoltaic array(Power purchase)Powerconditioner
Photovoltaic array(Power sale)

Distribution
board
Load at regular
operation

Load at autonomous
operation

Fig. 1 Example of solar power generation system configuration

3. Effect estimation(1) Calculation formula
Calculation of generated electric energy (kWh) at an intended facility
Reduced electric energy: Daily generated electric energy (kWh/day) x Self-consumption rate (%) of daily generated
electric energy x No. of operating days (days/year)
Daily generated electric energy: Photovoltaic array output (kW) x Daily amount of solar radiation of array surface(kWh/(m2・day)) x Total design factor x DC:AC ratio / Intensity of solar radiation (1 kW/m2)(2) Prerequisites for calculation
Installed capacity: 50 kW (equivalent to 25% of contract demand)
Array azimuth: 0º (building azimuth)
Inclination angle: 30º (optimum inclination angle of the relevant area)
No. of annual operating days: 365
Self-consumption rate: 100%
Amount of solar radiation of array surface: 4.04 (kWh/(m2・day)) (average value of the relevant area)*1
Total design factor: 0.7 *2
DC:AC ratio: 130%*3*1 NEDO "National Solar Radiation Data Map" NP-9703*2 NEDO "Guidebook for Introduction of Solar Power Generation"*3 Comments on the procurement price, etc. in FY2020, Calculation Committee for Procurement Price, etc.

4. Effects①②

Reduced power consumption

67,094

kWh/year%

Energy conservation rate–③

Saved amount of money

1,275

④

Reduction in crude oil equivalent

17.3

kL/year

CO2 reduction*

31.5

t-CO2/year⑤\1,000/year① x \19/kWh① x 9.97 GJ/1,000 kWh x 0.0258 kL/GJ① x 0.470 t-CO2/1,000 kWh(* For the CO2 emission factor, use the one provided by your contracted power company.)

40

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[Reference] Description of the common matters(2) Crude oil equivalentThis is used to evaluate energy amounts of electricity and different fuels by a common scale.
・Convert the heat quantity of the fuel (quantity x heating value), 1 (GJ), as crude oil, 0.0258 (kL).
・For electric power, convert the heat quantity of fuel required for generating and transmitting that electric energy into
crude oil.
(Energy of electric power, not heat quantity)

Heat qty. (GJ)

Heating value*

1 (kL)

x39.1 (GJ/kL)

⇒

39.1

1 (t)

x

50.8 (GJ/t)

⇒

50.8

1 (1,000 m )x44.8 (GJ/1,000 m )

⇒

44.8

Electric energy (daytime)*** 1 (1,000 kWh)Electric energy (nighttime)*** 1 (1,000 kWh)x9.97 (GJ/1,000 kWh)

⇒

9.97

x

9.28 (GJ/1,000 kWh)

⇒

9.28

LPG
City gas 13A**

3

3

Crude oil equivalent
volume (kL)⇒ 1.009x 0.0258(kL/GJ)⇒ 1.311⇒ 1.156⇒ 0.257⇒ 0.239(The calculations in the cases are partly simplified. For official reports such as periodical ones, comply with the respective methods.)* : The heating value is defined by the enforcement regulations for the Act on the Rational Use of Energy.
** : The heating value of the city gas uses the actual value of the supplied gas. A typical value is used in this Guidebook.
*** : In the cases provided in this Guidebook, the electric power is always converted on the basis of daytime values.

(3) CO2 emissions[For the fuel]As mentioned above, multiply a fuel amount by the heating value to calculate the heat quantity. Multiply this by a carbon
emission factor to calculate a carbon amount. Furthermore, for conversion of molecular weight, multiply by 44/12 to
calculate a carbon dioxide amount.
Type
Heavy oil A

Qty.

Heat qty. (GJ)

Carbon emission factor* (t-C/GJ)

1 (kL) ⇒39.1

x 0.0189

LPG
City gas 13A

1 (t) ⇒

50.8

x 0.0161⇒ 3.001 (1,000 m3) ⇒44.8

x 0.0136⇒ 2.23CO2 emissions (t)⇒ 2.71* Defined by the ministerial ordinance related to calculation of greenhouse gas emissions associated with the business activities of thespecified emitter.

[For electric energy]

Multiply the electric energy by the CO2 emission factor.
Electric energy

CO2 emission factor*

1 (1,000 kWh) x 0.470 (t-CO2/1,000 kWh)

CO2 emissions⇒ 0.470 (t)Ⅱ Energy Audit of Factories andResults

Qty.

RemarkThe emission factor 0.470 is used in the cases, but normally,
use the value of the contracted power company.

Ⅲ Energy Conservation
Improvement Proposals

Fuel and electric power in crude oil equivalent (example)
Type
Heavy oil A

Ⅰ Significance and Procedures ofEnergy Conservation(1) Electric energy unit price and fuel unit price
The electric energy unit price (average unit price including a basic charge) and fuel unit price are unified in the cases. Useyour actual unit prices for your on-site consideration.

* The Act on Promotion of Global Warming Countermeasures obligates a business operator exceeding a certain scale or output to report
the CO2 emissions of the previous year. The actual emission factor and post-adjustment emission factor used for reporting should beannual factors for each electric utility (**).

For the latest emission factor, see "Pages Related to Emission Factors by Electricity Utility"(https://ghg-santeikohyo.env.go.jp/calc/denki), etc. The emission factor, 0.470 (t-CO2/1,000 kWh), mentioned/usedin this guidebook is an alternative value (most recent 5-year average, calculated by the government, of the total
emission factor of utility generation and private power generation in Comprehensive Energy Statistics) in"Emission Factors by Electricity Utility (results in FY2019, published by the Ministry of the Environment and theMinistry of Economy, Trade and Industry on Jan. 7, 2021, partially added and updated on Jul. 19, 2021)".

Unauthorized reproduction prohibited, all rights reserved. Copyright (C) The Energy Conservation Center, Japan 2021

41

Where to Apply and Contact for Energy Audit
The Energy Conservation Center, Japan provides an energy optimized audit(there are certain requirements).
Download an application form from the Energy Conservation and Power-saving portal site(https://www.shindan-net.jp) and send it to the following address by fax, regular mail or E-mail.
■Headquarters(Energy Audit Department)

Igarashi Building, 2-11-5 Shibaura, Minato-ku,
Tokyo 108-0023
Hokkaido Keizai Center Building, 2-2 Kitaichijo-Nishi,
Chuo-ku, Sapporo 060-0001

Phone: +81-3-5439-9732
Fax:+81-3-5439-9738■Tohoku Branch

Main Denryoku Building, 3-7-1 Ichibancho, Aoba-ku,
Sendai 980-0811

Phone: +81-22-221-1751
Fax:+81-22-221-1752■Tokai Branch

Ito Building, 3-23-28 Marunouchi, Naka-ku, Nagoya
460-0002

Phone: +81-52-232-2216
Fax:+81-52-232-2218■Hokuriku Branch

Toyama Kogin Building, 5-13 Sakurabashi-dori,
Toyama 930-0004

Phone: +81-76-442-2256
Fax:+81-76-442-2257■Kinki Branch

Yotsuhashi KF Building, 1-13-3 Shinmachi, Nishi-ku,
Osaka 550-0013

Phone: +81-6-6539-7515
Fax:+81-6-6539-7370■Chugoku BranchInoue Building, 8-20 Kamihacchobori, Naka-ku,
Hiroshima 730-0012

Phone: +81-82-221-1961
Fax:+81-82-221-1968■Shikoku Branch

Takamatsu Kotobukicho Prime Building, 2-2-10
Kotobukicho, Takamatsu 760-0023

Phone: +81-87-826-0550
Fax:+81-87-826-0555■Kyushu Branch

Asako Hakata Building, 1-11-5 Hakataeki-Higashi,
Hakata-ku, Fukuoka 812-0013

Phone: +81-92-431-6402
Fax:+81-92-431-6405■Hokkaido Branch

Phone: +81-11-271-4028
Fax:+81-11-222-4634

Energy Conservation and Power-saving Portal Site

The Energy Conservation Center, Japan
Energy Conservation Technology Division

Phone: +81-3-5439-9733 Fax: +81-3-5439-9738
https://www.eccj.or.jp/
E-mail: ene@eccj.or.jp
Unauthorized reproduction prohibited, all rights reserved
Copyright (C) The Energy Conservation Center, Japan 2021
This booklet has been prepared in the project by the Agency for Natural Resources and Energy, "Subsidies
for Promotion of Optimized Energy Utilization for Small- and Medium-sized Enterprises in FY2021".
This print uses
environmentally-friendly
vegetable oil ink.

Recyclability
This print is recyclable
into printing paper.

2021.08/7K