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Production from the system more than covers all energy needs of this all-electric house.

What You Need to Know


Grid Tied PV The project consists of a full gut renovation of an existing single-family residence on Cottage Street (c. 1890), including the entire envelope and all mechanical and electrical systems. The energy efficiency measures include: Triple-pane Canadian fiberglass windows with low-e coatings; An air-tight envelope with exceptional thermal performance (R20 Basement, R34 Exterior Walls, R57 Roof) and a tested infiltration rate of less than 1 Air Change / Hour at 50 Pascals; A cold-climate Mitsubishi heat pump with a winter COP of 2.5 and a summer COP near 4; A high-efficiency HRV that delivers more than 2CFM/Watt, with heat recovery of 80%+; Energy Star appliances; LED cans and CFLs throughout; an air-source heat pump hot water from Stiebel Eltron; and a 12.5 kW photovoltaic system. A variety of insulating materials were used including: open cell foam in the exterior walls; closed cell foam in the basement and a flash coat in the roof rafters; dense-pack cellulose in remaining space of roof rafters; and two layers of rigid foam board on the exterior. During our first year of residence, we produced 14,898 kWh and used 11,686 kWh to provide all energy needs of the home. In other words, we are net producer of energy. See pre-renovation pictures and pictures throughout construction process at:

Other Benefits:

Goodwill for my business through neighborhood net metering.

Maintenance Requirements:

No servicing or maintenance to perform so far. Because of steep pitch of roof, snow sheds quickly and we lose few production opportunities even after a heavy winter snow.

Efficiency or Sustainability Improvements:

Spray Foam Open Cell Energy Star Appliances, FSC Certified Wood, Non-Toxic Products, Super Insulated Walls/ Roof, Thousand Home Challenge

Open House Info:

Please note: This property will be open from 12:00 PM to 3:00 PM only. From I-91 N: Exit 19 onto Rt. 9 E. Proceed about 6 miles and take a left onto North Pleasant St. Proceed through several lights for 0.5 mi and take a right onto Pray St (just after the Bank of Western Mass). Continue across Triangle St onto Cottage St. We are located 0.2 miles up Cottage St on the left. From I-91 S: Take exit 25 for MA-116 S. Take a left off the exit ramp and then take a right at the lights heading south on Rt 5/10/116. Proceed about 1 mi and then take a left to continue on Rt 116. Proceed 6.6 mi and take a left at light onto Meadow St. At the first light in 0.4 miles, take a right onto North Pleasant St. Proceed through UMass for 1.8 miles. Take a left onto Massachusetts Avenue at T-junction light. Continue straight through next set of lights at East Pleasant St. and turn left onto Cottage St. (across from Jones Real Estate office). We are located 0.2 miles up Cottage St on the left.

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