Sustainable Construction 

in Indian Country

Energy Evaluation and Recommendations

August 6, 2012

Pokagon Band of 

Potawatomi Indians

Dowagiac, MI 

Kekyajek Odanek Elder Housing
Table of Contents

Executive Summary .................................................................................................................................. 1

1. Analysis Approach ................................................................................................................................ 1

2. Facility Description ................................................................................................................................ 2

2.1 Building Envelope............................................................................................................................ 2

2.2 HVAC .............................................................................................................................................. 3

2.3 Domestic Hot Water ........................................................................................................................ 3

2.4 Lighting ............................................................................................................................................ 3

2.5 Additional Plug Loads...................................................................................................................... 3

3. Energy Consumption and Analysis ....................................................................................................... 4

3.1 Utility Consumption Benchmarking ................................................................................................. 4

3.2 Energy Consumption Profiles .......................................................................................................... 4

3.3 Breakdown of Energy Consumption ................................................................................................ 6

4. Energy Cost Reduction Measures ........................................................................................................ 7

4.1 ECRM 1: Lighting Upgrade ............................................................................................................. 8

4.2 ECRM 2: Geothermal System ......................................................................................................... 8

4.3 ECRM 3: Photovoltaic Array ............................................................................................................ 8

4.4 ECRM 4: Additional Attic/Ceiling Insulation ..................................................................................... 9

5. Additional Energy Reduction Measures .............................................................................................. 10

5.1 Install Low Flow Fixtures ............................................................................................................... 10

5.2 Develop an Energy Management Strategy ................................................................................... 10

6. Conclusions and Recommendations .................................................................................................. 11
1 

Executive Summary 

The Pokagon Band of Potawatomi in Michigan constructed 20 single-family elder units in 2005 

as part of an ongoing community master plan for Pokegnek Edawat Dowagiac. Key 

sustainable elements of this phase of the master plan included: dense deep-rooted 

vegetation, permeable pavement, clustering and placement of houses to preserve topography 

and existing vegetation, rain gardens, bioswales, and ENERGY STAR appliances. Each of the 

one-story single-family homes three bedrooms, a two car attached garage, and a screen 

porch. Three different floor plans were used for the 20 houses ranging in size from 1,962 to 

2,593 square feet. 

This report provides information and strategies on how to reduce the annual operation cost 

through load reduction and energy efficiency improvements. It compares a baseline analysis 

of the design by Wightman & Associates, Inc and the actual utility bill consumption and costs 

verses an analysis of proposed alterations to the homes suggested by the Sustainable 

Construction in Indian Country (SCinIC) team. 

1. Analysis Approach 

The basic approach used to develop this report involves several steps. First, initial information 

is collected from the client about the building’s design, building usage, and utility data. Then a 

site visit is conducted where data and observations are recorded by the project SCinIC team. 

A baseline energy model is constructed in computer modeling software that performs building 

energy simulations. The HVAC load design and analysis software e-QUEST version 3.64, was 

used to model the building. This modeled data is calibrated to match the actual building 

energy usage as shown by the utility bills and then used as a baseline for evaluating the 

energy cost reduction measures (ECRMs). The program calculates the amount of energy (and 

the resulting utility cost of that energy) the building is expected to use over an entire typical 

weather year. Model inputs are taken from information collected during the site visit and 

information provided by the client. The weather file for e-QUEST was taken from the Eau 

Claire, Michigan weather station. 

Subsequently, the project SCinIC team performs computer analyses of the ECRMs. The 

baseline model is changed to reflect the implementation of theses ECRMs and the computer 

model generates the expected energy consumption and utility costs. When necessary, some 

ECRMs are evaluated outside of the modeling software using spreadsheet calculations. 
2 

2. Facility Description 

Constructed in 2005, this 2,593 ft2 single story single-family home is used as elder housing 

and is one of 20 similar houses. Each single-family home was constructed from 1 of 3 different 

plans ranging in size from 1,962 ft2 to 2,593 ft2

. The largest of the plans was used for 

evaluation in this report. Each house has 3 bedrooms, 2 bathrooms, an attached two car 

garage, screen porch, living room, kitchen, dining area, laundry room, and basement. 

It is assumed that 6 people will be living in each unit (two people per bedroom). While 

occupancy is highly dependent on the individual lifestyles of the elders and what additional 

family members may be living with them, it is assumed that the elders living in the units will 

spend most of their time at home. Therefore it is assumed that the elders will primarily be in 

the units 80% of the time during the week (approximately 134 hours/week). 

2.1 Building Envelope 

Walls: The typical wall construction from the inside to outside is 5/8” gypsum board, 2x6 wood 

stud construction at 16” on center with 5 1⁄2” fiberglass batt insulation, vapor barrier, and 1⁄2” 

oriented strand board with #15 felt and vinyl siding. It is estimated that the wall assembly has 

a thermal resistance rating (R-value) of R-22.

Roof: The roof is gabled with a 8:12 slope. It is constructed with 2x6 pre-engineered trusses 

at 24” on center, covered in 1⁄2” CDX plywood, #15 felt, and light gray asphalt shingles. There 

is R-38 blown insulation above the ceiling. 

Floor: The basement floor is a 4” reinforced concrete slab on 6 MIL Visqueen and granular fill 

compacted to 98 M.P.D. The main floor is 2x10 wood floor joists at 16” on center with 3⁄4” 

plywood subfloor. The bedrooms and living room are carpeted. The dining area is hardwood, 

and the kitchen, foyer, mud room, laundry room, and bathrooms are sheet vinyl. The screen 

porch, garage, patio, and basement are sealed concrete. 
3 

Windows: All windows have 7/8” insulated glazing, insect screen, and grilles.

2.2 HVAC 

The current NDG proposal of the building places all HVAC equipment in the basement. 

Assumptions were made according to the following heating/cooling design schedule detailed in 

the plans: 

Heating/Cooling: Provide a 93 high efficiency gas forced air furnace with humidifier, a-coil, 

and electronic air filter and condenser system to be sized and designed with all controls to 

maintain the following conditions: 72 degrees (F) inside temperature at 0 degrees (F) outside 

and wind velocity of 15 MPH; 75 degrees (F) inside temperature at 95 degrees (F) outside in 

the summer. System to be controlled by low voltage thermostat with subbase including fan 

switch. Furnace to have a variable speed motor. Outdoor condenser to be high efficiency type 

with 2 speed motor. System to have outlets in all rooms and high returns located as required. 

Returns from all rooms except the kitchen, laundry and bathrooms. All trunk, risers, runs and 

returns to be completely sealed in aluminum, galvanized steel or composite ducts. If ducts cut 

through house plate, contractor is to supply and install a steel plate, 1/8” thick by 3 1⁄2” wide 

with 4 nails. All ducts in outside wall and unconditioned areas to be insulated. All risers to 

have balancing dampers. Use canvas connectors at furnace.

Ventilation: Ventilation air will be provided by infiltration. Each bathroom also has an exhaust 

fan rated at 80 CFM. 

2.3 Domestic Hot Water 

Design calls for a 40 gallon high efficiency natural gas water heater (Lochinvar ETN 040-4) 

with vent through roof and bird screen. 

2.4 Lighting 

When day-lighting from the windows is insufficient, lighting in the building is provided by 

incandescent light fixtures throughout the house, a 4’ T8 in the laundry room, 3’ T8s above the 

sinks in the bathrooms, and from the ceiling fans with incandescent fixtures in the living room 

and screen porch. 

Assumed lighting power density for the base model was 0.80 W/ft2 using a 60 W incandescent 

lamp in each fixture (including recessed can lights and ceiling fans) throughout the house, and 

a 4’ 32 W T8 and 3’ 25 W T8 linear fixture with rapid start electronic ballast in the laundry room 

and bathrooms respectively. 

2.5 Additional Plug Loads 

Additional plug loads in the building include typical residential appliances such as task lighting, 

TVs, washer and dryer, and standard kitchen equipment (refrigerators, stove, and 

microwaves). 
4 

3. Energy Consumption and Analysis 

3.1 Utility Consumption Benchmarking 

Utility data was provided for 6 of the 20 elder houses for the 2011 calendar year. Of these 6 

sets of data, two were for the same floor plan that was chosen to evaluate for this report. The 

Pokagon receive their electricity through COOP Electric and it is delivered at an estimated rate 

of $0.12 per kWh. Their natural gas is supplied by SEMCO Energy at an estimated rate of 

$0.71 per therm. These rates include meter fees and taxes. The estimated annual energy use 

intensity (EUI) of the first elder home is 69 kBtu/ft2/yr and the estimated annual energy cost 

intensity (ECI) is $1.20 /ft2. For home 2 the EUI is 67 kBtu/ft2/yr and the ECI is $0.99 /ft2. 

These two values can be used to benchmark the energy performance of the current housing 

against similar buildings. 

Utility Consumption Analysis Home 1 

Average Annual Consumption Annual Costs Average Unit Cost 

Electricity 13,797 kWh $ 1,656 74% $0.12 $/kWh 

Natural Gas 819 therms $ 586 26% $0.71 $/therm 

Total: $ 2,241 

Total Conditioned Area 1,873 ft2 

Electricity Use Intensity 7 kWh/ft2/yr Natural Gas Use Intensity 0.44 Therms/ft2/yr

Energy Use Intensity 69 kBtu/ft2

/yr Energy Cost Intensity $ 1.20 $/ft2/yr 

Electricity is provided by COOP Electric and natural gas is supplied by SEMCO Energy 

Utility Consumption Analysis Home 2 

Average Annual Consumption Annual Costs Average Unit Cost 

Electricity 10,056 kWh $ 1,207 65% $0.12 $/kWh 

Natural Gas 913 therms $ 653 35% $0.71 $/therm 

Total: $ 1,859 

Total Conditioned Area 1,873 ft2 

Electricity Use Intensity 5 kWh/ft2/yr Natural Gas Use Intensity 0.49 Therms/ft2/yr

Energy Use Intensity 67 kBtu/ft2

/yr Energy Cost Intensity $ 0.99 $/ft2/yr 

Electricity is provided by COOP Electric and natural gas is supplied by SEMCO Energy 

3.2 Energy Consumption Profiles 

The SCinIC team analyzed one year of electric and gas data provided by the client. The utility 

data covers the months from January 2011 through December 2011. The home was then 

modeled using the closest weather station, Eau Claire, Michigan, which recorded 6,215 

heating degree days and 801 cooling degree days. Degree days are indicative of the duration 

and intensity of the heating and cooling seasons and are used in this analysis to track how 

electricity and gas usage correspond to seasonal weather changes. 
5 

Figure 1. Electricity Consumption vs. Cooling Degree Days 

Figure 1 compares the Pokagon elder home’s electricity usage with cooling degree days and the 

modeled electricity usage. Electricity is used for lighting, cooling, plug loads, and fans and pumps. The 

base electrical load for Home 1 is approximately 800 kWh per month and it is about 600 kWh per month 

for Home 2. The homes use this amount of electricity regardless of weather. The graph shows that 

additional electricity use does correspond with the cooling degree days except for the additional use in 

September which could be attributed to a delayed change in seasons, and a spike in December for 

Home 1 which could be from humidification or space heating. The difference in usage for the two 

homes is attributed to the difference in occupancy patterns. The modeled electricity use comes within 

14 percent (average of home 1 & home 2) of the metered annual electricity use. 

Figure 2. Gas Consumption vs. Heating Degree Days 
6 

Figure 2 compares the building’s natural gas usage with heating degree days and the modeled gas 

usage. Natural gas is used for the furnace and domestic hot water. The homes’ gas use does follow 

the heating degree days. The base natural gas consumption is simply the amount of gas used to 

provide domestic hot water. The modeled gas use comes within 6 percent of the metered annual use 

and is acceptable for the purposes of this report. 

3.3 Breakdown of Energy Consumption 

Using the modeled energy data, an energy consumption profile was created for the Pokagon Elder 

Housing. Figure 3 shows the energy consumption breakdown for the homes. The largest category of 

energy usage is space heating. The second largest consumer is miscellaneous loads (including plug 

loads, humidification, and space heating), and then lighting. 

Figure 3. Energy Consumption Breakdown 

The energy cost breakdown is illustrated in Figure 4. When energy consumption is translated to energy 

cost, the most costly operational categories are revealed: (1) Space Heating, (2) Lighting, (3) 

Miscellaneous loads. These are the first areas that should be targeted for energy savings. 
7 

Figure 4. Energy Cost Breakdown 

4. Energy Cost Reduction Measures 

Energy conservation is best achieved through a multifaceted approach that involves load reduction, 

efficiency improvements, and renewable generation. Addressing any one of these pathways will save 

energy. 

Load reduction, whether no cost or low cost, should be the first step. Load reduction involves 

managing energy consumption by simply turning things off when not needed or implementing control 

systems to help manage unnecessary energy use. Examples of load reduction include using nighttime 

thermostat setbacks or turning off lights in well-lit areas on sunny days to reduce lighting loads. 

Envelope upgrades such as adding insulation or window shades can result in load reduction but usually 

require large capital expenditures. 

Energy efficiency improvements should be considered next. While typically more expnsive than load 

reduction, energy efficiency improvements are more cost effective than implementing renewable energy 

generation. Efficiency improvements involve replacing old or failing systems with modern technologies 

which perform the same function while consuming less energy. Examples of energy efficiency 

improvements include installing boilers with greater heating efficiency improvements include installing 

boilers with greater heating efficiencies or installing lighting with increased luminous efficacy. 

The final step is energy generation. This step offsets a portion of the remaining energy consumption 

with onsite energy generation. Onsite energy generation is purposefully recommended after load 

reduction and efficiency improvements. Accomplishing the first two steps makes it possible to install 

lower capacity, therefore less expensive, generation systems. 

The following sections of the report address load reduction and efficiency improvements because these 

measures will be the easiest and most cost effective options. 
8 

4.1 ECRM 1: Lighting Upgrade 

The current lighting in the homes is provided by incandescent light fixtures throughout the house, a 4’ 

T8 in the laundry room, 3’ T8s above the sinks in the bathrooms, and from the ceiling fans with 

incandescent fixtures in the living room and screen porch. This calculates to a lighting power density of 

0.80 W/ft2

 using a 60 W incandescent lamp in each fixture (including recessed can lights and ceiling 

fans) throughout the house, and a 4’ 32 W T8 and 3’ 25 W T8 linear fixture in the laundry room and 

bathrooms respectively. By replacing the 60 W incandescent lamps with 13 W CFLs and using a 28 W 

T8 instead of the 32 W T8 in the 4’ fluorescent fixture, 2,695 kWh may be saved annually resulting in an 

annual cost savings of $299. This lifespan of lighting is calculated at 5 years. The replacement of the 

incandescent lamps with CFLs will pay back in under a year, so implementation of this measure is 

highly recommended. 

Table 1: Lighting Upgrade Energy Savings 

ECRM 1: Lighting Upgrade 

Annual Energy Savings Economic Analysis 

kWh Therms Cost % Energy Investment IRR1 NPV2

2,695 -34 $299 72% $165 180% $1,077 

4.2 ECRM 2: Geothermal System 

The purpose of a geothermal system is to reduce the use of traditional energy sources. This system 

uses the temperature of the earth to moderate the temperature of water which is pumped through the 

structure. When analyzed in the e-Quest model, the following results indicate this measure should be 

implemented only if fuel switching is the goal as the measure will not pay off in its lifetime (20 years). 

Table 2: Geothermal System Energy Savings 

ECRM 2: Geothermal System 

Annual Energy Savings Economic Analysis 

kWh Therms Cost % Energy Investment IRR NPV 

-2,043 711 $266 50% $25,000 -12% -$20,652

4.3 ECRM 3: Photovoltaic Array 

The purpose of a photovoltaic array is to reduce the use of traditional energy sources. This system 

captures solar energy and converts it to electricity for use in the home which cuts down on the amount 

of energy that must be purchased from the utility company. When analyzed using the PV Watts 

calculator, the following results indicate that a 4.0 kW array in the South Bend, IN area will produce 

4,490 kWh annually. The investment cost is calculated with the 30% ($8,400) federal/state tax credit. 

 

1

 Internal Rate of Return: Rate of return on investment for project 

2

 Net Present Value: Shows project earns this amount more or less than the desired rate of return (5%) 
9 

Even with the tax credit, the calculator shows that this array would not pay back within the photovoltaics 

25 year lifespan. 

Table 3: Photovoltaic Array Energy Savings 

ECRM 3: Photovoltaic Array 

Annual Energy Savings Economic Analysis 

kWh Therms Cost % Energy Investment IRR NPV 

4,490 $539 38% $19,600 -3% -$11,434

4.4 ECRM 4: Additional Attic/Ceiling Insulation 

By adding attic/ceiling insulation to at least R38, heating and cooling losses may be minimized. The 

calculations below use $1.20/ sq. ft. for insulation and labor. If this cost could be reduced to $0.90/sq. 

ft. the additional insulation would pay for itself within its 20 year lifespan. 

Table 4: Additional Attic/Ceiling Insulation Energy Savings 

ECRM 3: Attic/Ceiling Insulation 

Annual Energy Savings Economic Analysis 

kWh Therms Cost % Energy Investment IRR NPV 

56 159 $119 7% $3,112 -2% -$1,548 
10 

5. Additional Energy Reduction Measures 

5.1 Install Low Flow Fixtures 

Although stormwater and domestic water management was not addressed as part of the 

building energy analysis, a large amount of savings can be achieved by reducing the amount 

of hot water used on a daily basis. Research shows that along with energy, access to fresh, 

clean water is also becoming a dwindling resource and shortages in certain areas of the United 

States are already causing water to be the next leading concern. Reducing water consumption 

will not only save water, but it will reduce natural gas use by reducing hot water use. 

Low-flow showerheads and aerators are inexpensive, simple to install, and save hot water 

heating costs. Recommended are low flow showerheads (1.6 GPM or less), faucet aerators 

(1.0 GPM or less) and kitchen sink aerators (1.8 GPM or less). Some faucet aerators will 

reduce flow to 0.5 GPM. 

5.2 Develop an Energy Management Strategy 

Organizations that adopt and practice an energy management strategy are rewarded with 

lower energy use. These plans are very effective and are considered low cost. The United 

States Green Building Council (USGBC) recommends using an energy management plan to 

save 10% of energy use. The SCinIC team recommends this plan to the Pokagon community. 

Here are the steps that describe an energy management strategy offered by ENERGY STAR. 

1) Make a Commitment: Recognize that the economic, environmental, political, and social 

impacts of energy consumption are sufficient motivation to change our energy use patterns. 

2) Assess performance: Make a personalized accounting of energy use and costs. 

Benchmark your site by comparing its energy performance with similar sites. 

3) Set Goals: Review your objectives and constraints. Establish priorities and set 

measurable goals with target dates. 

4) Create an Action Plan: Define the technical steps. Apply proven methods to increase 

energy efficiency or get specialized guidance. Assign roles and resources. Consider 

rolling savings from earlier efforts into future, more complex initiatives. 

5) Implement Action Plan: Install equipment and change operational procedures. Establish 

a maintenance schedule. Train equipment operators and building occupants on the 

changes. Track and monitor conditions. 

6) Evaluate Progress: Compare current performance to established goals. Understand 

what worked well in order to identify best practices. Adjust procedures, goals, and 

schedule the next evaluation. 
11 

7) Recognize Achievements: Provide internal recognition for the efforts and achievement of 

individuals, teams, and facilities. Seek external recognition from government agencies, 

media, or third party organizations. 

The quickest, easiest, and cheapest way to reduce loads during peak hours is to ensure 

that lights and equipment are turned off whenever they are not required. This could be 

achieved by developing better occupancy habits by the residents. Savings can also be 

achieved by changing the thermostat settings to minimum cooling during the peak day time. 

Thermostat should be set to 78 °F for occupied zones. 

6. Conclusions and Recommendations 

In summary, this report provides information and strategies on how to reduce the annual 

operation cost through load reduction and energy efficiency improvements. Table 5 includes a 

summary of the quantified results. These results also include calculations using the annual 

rate of inflation on electricity costs for Michigan. The cost/kWh increases on average by 

$0.0023 each year3 as shown in Figure 5 below. 

Figure 5: Michigan Average Cost/kWh by Year 

 

3 http://www.eia.gov/electricity/data/state
12 

Table 5: Summary of ECRMs 

Annual Energy Savings Economic Analysis Study 

Period ECRM kWh Therms Cost % Energy Investment IRR NPV SP4

Lighting 

2,695 -34 

$299 

72% $165 

180% $1,077 0.55 

5

with inflation $316 190% $1,144 0.52 

Geothermal 

-2,043 711 

$266 

50% $25,000 

-12% -$20,652 93.98 

20

with inflation $411 -9% -$18,931 60.83 

Photovoltaics 

4,490 $539 38% $19,600 

-3% -$11,434 36.36 

25

with inflation $618 -2% -$10,371 31.72 

Attic/Ceiling 

Insulation 56 159 

$119 

7% $3,112 

-2% -$1,548 26.09 

20

with inflation $120 -2% -$1,541 25.96 

Total: 5,198 836 $47,877   

 

4 Simple Payback: The number of years it will take the savings of the project to payback the initial investment. If 

this number exceeds the lifespan of the measure (study period), it is not recommended for implementation.