Electrify Everything:
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Racusin weatherization and electrification project
The Racusin home is a 2800 square-foot, single-story home built in 1989. Renovations in 2015 by New Frameworks Natural Building of Burlington included weatherization, changes to the existing heating system, and air source heat pumps. The renovation won an honor award in the 2016 Efficiency Vermont Best of the Best competition. Additionally, the owners joined an offsite community solar project in 2017 that offsets a large fraction of the house’s energy use. The weatherization project included sealing the envelope, addition of exterior mineral board, attic and eave cellulose, window weatherstripping, and interior mineral board in the garage. These changes reduced energy use by 78% and infiltration by 46%. The photo at left shows how the envelope improvements have eliminated any snow melt from the roof and consequent icicles. Heating updates included simplification of the existing radiant floor system, which eliminated a propane boiler. Three air-to-air mini-split heat pumps were also installed and they now carry the bulk of the heating load. These changes resulted in the elimination of propane from the house and a major reduction in the use of heating oil (see table 2 below). In 2017 the owners joined the Norwich Technologies Bridge Street community solar project, and now receive a credit on their electric bill from the output of 24 panels which reduces their bill by about 8,600 KWh/year. |
Table 1. Project Costs
The project cost a net of $132,000, including a solar component. The majority of this was the very thorough envelope improvements carried out by New Frameworks.
The project cost a net of $132,000, including a solar component. The majority of this was the very thorough envelope improvements carried out by New Frameworks.
Table 2. Project Results
The project resulted in the elimination of propane and a substantial reduction in fuel oil use. There was an increase in total electricity use as much of the remaining heating load was moved from fossil fuels to the electric heat pumps. However, the community solar field now provides about half of the electricity used by the house, resulting in substantial savings overall.
Fuel and electricity cost approximately $4,100 in 2014 before the project and was reduced to about $1,800 in 2020, about a 44% reduction in cost. Additionally, the carbon footprint of the house was reduced by about 3.6 metric tonnes a year.
The project resulted in the elimination of propane and a substantial reduction in fuel oil use. There was an increase in total electricity use as much of the remaining heating load was moved from fossil fuels to the electric heat pumps. However, the community solar field now provides about half of the electricity used by the house, resulting in substantial savings overall.
Fuel and electricity cost approximately $4,100 in 2014 before the project and was reduced to about $1,800 in 2020, about a 44% reduction in cost. Additionally, the carbon footprint of the house was reduced by about 3.6 metric tonnes a year.