Renewable Energy Systems (ME 416/516) Final Design Project
Analyze an existing small residential home to identify how to reduce the energy use from the baseline conditions. Document what improvements you would recommend by showing evidence of why the improvement is beneficial (energy savings, carbon savings, and/or cost savings). Evidence includes a written explanation and your calculations comparing the existing system to your proposed recommended improvement. You must include at least 1 RES in your recommended improvements. Project Overview Design a renewable energy system to achieve the following goals:
1) Achieve at least a 50% reduction in energy use compared to the baseline design – documented by BTU input required for both cases. (i.e. convert all energy use into Btu/yr AND show all calculations)
a. Detail the baseline energy use and energy cost b. Detail your proposed system’s energy use and energy cost
2) State why your system is an optimum investment. (i.e. – justify by your system costs and your return on investment)
3) Bonus a. For energy reduction greater than 50% b. For a better overall return on investment compared to the baseline case (note – you
must document your cost estimates and include installation costs) Building: Single story, residential house 2”x12” roof construction – 11.25” Fiberglass Batt (R‐38) Wood, 2”x6” wall construction – 5.5” Fiberglass Batt (R‐19) Infiltration/ventilation = 0.45 Air Changes per Hour Windows = 0.6 U-value, 0.4 SHGC Base design: Natural gas furnace, 78% efficiency Electric air conditioning, SEER = 13
70F temperature setpoint, 24/7
The minimum information required in your final report is outlined in the following table. All information must be documented by sample calculations, explanations of methods and appropriate documented sources for costs. Include detailed tables, charts, graphs, pictures, and other supporting information to fully document your analysis in order to achieve the maximum grade. Your analysis should be clear and well formatted.
Table of Required Information in Final Report
Parameter Current Proposed
Lighting Electrical Energy Use (kWh/yr) 720
Cooling Electrical Energy Use (kWh/yr) 961
Appliances & Plug Loads – Electrical Energy Use (kWh/yr) 2,650
Other Electrical Load (if any) 0
Total Electrical Energy Use (kWh/yr) 4,331
Space Heating Fuel Energy Use (Therm/yr) 604
Water Heating Fuel Energy Use (Therm/yr) 186
Total Natural Gas Fuel Energy Use (Therm/yr) 790
Other Energy (if any) 0
Total Energy Use (MMBtu/yr)
Pounds CO2 /yr Produced*
Renewable Energy Generated (-MMBtu/yr) 0
Total Net Energy Use (MMBtu/yr)
% Conventional Energy Reduction
CO2 Saved/yr* (total pounds & % savings)
Total Return on Investment (simple payback period)
Energy Savings/yr (total MMBtu/yr & % savings)
Energy Cost Savings/yr ($/yr)
* use 1,380 lbs CO2 per megawatt-hour of delivered electricity Table of Max Grade for Final Report
Parameter Max Grade
416 / 516
50% Conventional Energy Reduction 70% / 0% 70% Conventional Energy Reduction 80% / 70% 80% Conventional Energy Reduction 90% / 80%
Net Zero 100% / 90% 100% RE (off-grid) 110% / 100%
Minimum: 1 RES added
ME 416/516 Final Project Base Assumptions for Current System
Furnace efficiency 78% Furnace Natural Gas Use 604 Therm/yr
Furnace – heat into house 47,112 MBtu/yr 30,000 Peak Load – Btu/hr
Air conditioner SEER 13 Air conditioner Elec. Use 961 kWh/yr
Air conditioner – heat out of house 12,493 MBtu/yr 20,000 Peak Load – Btu/hr
# of Lamps (60 W incandescent) 12 Lighting (Average ‘On time’ per lamp) 1,000 hr/yr
Total Lighting W 720 Lighting Elec. Use 720 kWh/yr
Water Heater Energy Factor (50 gal tank) 54% EF*
Water Heater Natural Gas Use 186 Therm/yr Hot Water – average use (125F) 44 gal/day
Appliances & Plug Loads Elec. Use 2,650 kWh/yr (Conventional Appliances)
*Energy Factor (EF) is an annual measure of the useful energy coming out of your water heater divided by the amount of energy going into the water heater to heat the water.
Table of Energy Costs
Parameter Metric
Natural Gas $0.90/therm
Electricity $0.10/kWh Electricity (sale price back to electric
utility) $0.04/kWh
Diesel (off-road) $3.00/gal
Biomass / wood $225/cord