Source:JASE-W Japanese Smart Energy Products & Technologies

https://www.jase-w.eccj.or.jp/technologies/index.html

O-04

Keywords

Y2

deviceZ4

electricity

S5

renewable energy

LTechnical ServiceHeat Pump & Thermal Storage Technology Center of Japan

Commercial Heat Pump Air Conditioning System(Multisystem Air Conditioner for Highly-Efficient Buildings)
Featuresu The multisystem air conditioner for highly-efficient buildings is a heat pump air conditioning systemcomprising a single external unit connected to multiple internal units. The external unit can also beconnected to other external units to form a large single unit, thereby linking multiple internal units together.
The system is energy-efficient and is suitable for use in large office buildings, hotels and public facilities
requiring independent temperature control in each room.
u Various models have been developed including a cooling and heating switching model, simultaneous
cooling and heating model, ice thermal storage model, replacement (for cooling and heating switchingmodels), and heat pumps for cold regions; latent heat and sensible heat separation air conditioning
systems (humidity control external air processing unit); and water-cooling methods.

Basic Concept or Summary
For cooling and heating commercial buildings using the heat pump principle.
Unlike central systems that use water pipes, the system uses refrigerant pipes to utilize direct heat pumpcycles between internal and external units.
Since the internal unit and the external unit come in a set, the system can be handled as fitting rather thana fixture. As a result, designing and arranging for equipment materials are simple, and energy saving
performance is less subject to installation conditions.
Due to the wide variety in product line, there are equipment to suite each type of building and use (refer tothe information below).
1: Heat pump for cold regions
When the outside air temperature falls below a certain level, the workload on conventional
compressors increases and the operational efficiency drops. In contrast, high heating heat pumps aredesigned for application in cold regions, enabling highly efficient heating even with outside
temperatures of -25 °C.

2: Ice thermal storage air conditioning system (Eco Ice)
The Ice thermal storage air conditioning systems
makes use of less expensive nighttime electricity tostore energy in thermal storage tanks in the form of
ice and then uses the cold energy for air conditioning
during the day. This system minimizes variations inthermal load by catering to daytime air conditioning
loads using stored cold heat. Suppressing peaks in air
conditioning loads this way helps to keep heat source
equipment capacity low, enhance system efficiency
and improve air conditioning economy.

Uses power at night toproduce ice.

The stored ice provides
cooling in the day.

The night unit air conditioning produces
ice by chilling the heat exchanger in thethermal storage unit.

The stored ice provides cooling in theday.

Interior unit

Interior unit
Absorbed heat
Released heat

Released heat
IceIceThermal storage unit Exterior unit

Thermal storage unit Exterior unit

3: Latent heat and sensible heat separation air conditioning system (humidity control external air processing unit)
There was a limit to the level of energy saving and comfort that could be attained from cooling by lowering
the temperature and humidity at the same time (humidity was left to chance). Coefficient of performance(COP) can be improved by raising the evaporation temperature of the refrigerant flowing through the heatexchanger in the internal unit. However, this will reduce the temperature difference between the air and therefrigerant, lower the dehumidification performance and, consequently, not alleviate discomfort from highhumidity. The independent humidity & temperature control air conditioning system combines an external
regulator which can adjust humidity as required, and a highly-efficient multisystem air conditioner forbuildings mainly for temperature management. This new system is thus capable of regenerating andabsorbing humidity even at low temperatures and supplying continuously powerful humidity control while
significantly cutting energy consumption to create a comfortable living environment.
Absorption heat exchanger
emits moisture and adds humidity

Absorption heat exchanger
absorbs moisture from the air

Recycle side
Insideair

Supplies
air to room

Absorption side
Insideair

Refrigerant
flow
Supplies
air to room

Air flowCompressor
Outsideair
Alternating

Compressor

Discharges
air outside

OutsideairDischarges
air outside

Absorption side

Recycle side

Absorption heat exchanger
emits moisture and adds humidity

Absorption heat exchanger
absorbs moisture from the air

Effects or Remarks
u Commercial Heat Pump Air Conditioning System (High-performance Building Multi-Function Air Condition)<Example of standard energy consumption efficiency for top-runner Building Multi-function Air Conditioners (indoorunit individual control)>*Target years are each year after 2015
*APF (Annual Energy Consumption Performance Factor = Total Required Annual Air Conditioning Capacity/PowerConsumption per Model for the Period
[APF]
76

5.7

5.7
5.05

54.8

4.4

43
2
10

Contact:

10kW

20kW

30kW

40kW

50kW

[Cooling Capacity]

Heat Pump and Thermal Storage Technology Center of Japan
International & Technical Research Department
1-28-5 Hulic Kakigaracho Bldg., 6F, Kakigaracho Nihonbashi, Chuo-ku, Tokyo, Japan
Tel: 03-5643-2401 Fax: 03-5641-4501 URL: http://www.hptcj.or.jp/e/index.html

O-04