Final Report on renewable energy feasibility for the

Final Report on renewable energy feasibility for the Bridgeport Indian Colony Prepared by Josiah Johnston Renewable and Appropriate Energy Lab University of California Berkeley

Feasibility of Large-Scale renewable investment • Looked at projects 1 MW and larger • Ruled out large scale solar for not making a return on investment • Examined 37 sites for utilityscale wind farms and geothermal plants. • No project would produce a return on investment • Medium scale solar (300 -600 k. W) might be financially viable.

Lower Heating bills with Solar Heating and Weatherization • Most houses could save 1 or 2 pallets of firewood annually by installing solar retrofits • Adding insulation to walls and ceilings would reduce heat losses by 20% and take over 9 years to pay for itself with energy savings • I have a lead on implementation funds if the tribe wants to pursue this

Running the electric meter backwards: Solar and Wind on reservation • Wind is not practical – Wind speeds are too low to make enough electricity to justify expense • Solar is practical – Would take less than half an acre of land – Would cost around $500, 000 – At current retail prices of $0. 17 / k. Wh, the savings in electricity bills would pay for the system in 12 to 15 years – Major parts come with 15 to 20 year warranty – System size of 67 k. W (with tracking) or 91 k. W (without tracking) would supply ~100% of reservation’s electricity

Solar Hot Water • I looked at four different systems to get the range of costs and performance. • Costs $7, 000 or 8, 000 per house. – $5, 000 or 6, 000 with a 30% federal tax credit • Saves 150 to 225 gallons of propane per year – $450 to $675 per year at $2. 94 per gallon – Cuts propane use by 35 -50%, depending on collector and number of people • All systems used flat-plate collectors with a closed-loop heat exchanger and active pumping. • Evacuated tube collectors would also work well for your climate. They would provide higher temperatures and work better on cloudy days, but cost significantly more than flat-plate collectors.

Water heater Current hot water heater

Solar + Water heater Solar Collectors (on roof) Storage tank with built in heat exchanger. Pre-heats and stores water for hot water heater Current hot water heater

Solar water heater estimates System Cost Propane Cost after saved Propane 30% tax annually, saved gallons annually, % credit Annual savings at $2. 94 per gallon Current annual fuel costs CO 2 savings (estimate over system d) life, tonnes Skyline 5 - 60 sq. ft. , 5 people $8, 090 $5, 663 229 42% $673 $1, 615 93 Skyline 5 - 40 sq. ft. , 4 people $7, 190 $5, 033 156 36% $459 $1, 283 63 AET Propack - 52 sq. ft. , 4 people $7, 399 $5, 179 214 49% $629 $1, 283 87 AET Propack - 52 sq. ft. , 2 people $7, 399 $5, 179 155 72% $454 $634 63 AET Propack - 52 sq. ft. , facing Southwest $7, 399 $5, 179 207 47% $609 $456 to $503 $1, 283 84 Rheem, 2 -5 people $5, 200 to $8, 280 155 to 171 57 to 64

Solar Hot Water Cost breakdown $ 9 000 $ 8 000 $ 7 000 $ 6 000 $ 5 000 $ 4 000 $ 3 000 $ 2 000 $ 1 000 $- Installation Balance-of-system Tank Collector Skyline 5 - 60 sq. ft. , 5 people. Skyline 5 - 40 sq. ft. , 4 people AET Propack - 52 sq. ft. , 4 people Propane saved, gal 250 200 150 100 50 0 Skyline 5 - 60 sq. ft. , 5 people. Skyline 5 - 40 sq. ft. , 4 people AET Propack - 52 sq. ft. , 2 people AET Propack - 52 sq. ft. , facing Southwest