We cut the carbon dioxide emissions of our 5300sf 1970's house by 43 tons per year getting us to a year round zero-carbon footprint. We are not only saving money, our bills (for heating oil and electricity) are down $11,500 a year, but we are earning a 15% return on our investment. That's 15% after tax and with no volatility. Much better than my stock and bond investments! For more information, check out www.greenzerocarbonhome.com.
Building Type Summary:
Note that HERS index and Energy Star score are only available on new construction this is a renovation. There are no awards that I am aware of that apply to renovations. Perhaps you should start one? Since 99% of the US housing stock is already existing successful retrofits are important to publicize. Especially those that make money. None of your case studies shows the investment or return. In fact your case studies make no mention of money and therefore a reader cannot tell if this makes financial sense for them.
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Annual HDD :
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Number of stories:
Conditioned Floor Area:
Unconditioned Floor Area:
Total floor area of project (all buildings):
Gentle slope, mostly wooded
All wood was FSC certified
All paint was zero VOC
15kW roof mounted solar PV system
2 Bosch 5 ton ducted heat pumps
Heat pump hot water tank
Annual renewable energy generated:
Electric Utility Company:
Gas Utility Company:
Datasets and Utility Bills sources and reliability:
Annual heating oil data is 100% accurate for delivery records. Daily use is from gauges on the oil tank and is not as reliable. It is pretty good if averaged over about 5 days.
Electricity data is from Eversource bills and an Efergy whole house meter. It is 100% accurate.
Solar power data is from the Solar Edge reporting system and has been audited to the net-metering credits on my Eversource bills
Electricity amount (imported from grid):
Electricity amount (credited or exported to grid):
Net electricity usage (purchased electricity):
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Above grade wall assembly:
2x4 walls with fiberglass insulation, approx R12
Space heating - Manufacturer & Model:
Space cooling - Manufacturer & Model:
Domestic hot water - Manufacturer & Model:
Domestic hot water - capacity:
We did it ourselves after a lot of research
Energy Modeling Software:
My own spreadsheets. I created model of our house that has a R-squared of 80% to the actual energy use of the house.
Outcome of project goals:
We got to a zero carbon footprint, zero utility bills and are making a 15% return on investment
All paid in cash
Total Cost of Project:
Gross Cost of Renewable Energy System:
Value of Tax Credits for renewable energy systems:
Net Cost of renewable energy systems:
30% federal tax credit on solar panels, about $23,000
MA SREC2 solar power subsidy, about $29,000
$1500 utility rebate on heat pumps
Annual Electric Savings:
Annual Revenue from SRECs or other renewable energy credits:
Get all the incentives and the low cost, or zero interest, state loans. Get Massive to pay for the insulation.
Foundation wall R-value:
Above grade wall R-value:
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Cost per square foot of Conditioned Space:
Number of Bathrooms:
Renovation. Added triple glazed windows. Added R10 insulation to roof and R38 to basement.
Renewable Energy Sources:
Other Purchased Fuels Description:
Summary of enclosure strategy/description:
renovation of existing 10"x2" joists on flat roof
Loewen triple glazed patio doors. R4 on lower floor R 5 on upper floor.