Wool-Blanketed Solar Home Sends Electrons to Swedish Grid
Here’s a new solar home, designed from the start not just to supply the home’s occupants with 100% of the electricity they need, but to ship its surplus electrons to the grid.
Karin Adalberth, a doctor of building physics, worked with her local green utility E. ON to design the solar plan for Villa Akarp, which she is building near Malmo in Sweden. During the long dark winters of Sweden, her house will buy electricity from the grid. During summers, her house will supply the grid.
She calculated the solar needs based on her annual energy usage, and then she created the roof to be the exact size and angle that is just perfect for selling her solar electrons off her roof. (One of the great advantages of building from scratch!)
The house will sell back about 4,000 kilowatt-hours of electricity annually while only purchasing 2,600 kilowatt-hours, creating a positive net energy ratio for the year.
Many energy efficiency measures enable a house this size to get by on relatively few kilowatthours of electricity for the year.
The home is protected from Sweden’s frosty winters with a thick wool “blanket” of insulation 5 times as thick as average, enough to save the average family about 75 percent in energy costs.
Foam insulation lines the foundation and triple-glazed windows prevent air from escaping while also letting in lots of natural light. Solar thermal heating keeps baths (and the radiators) piping hot on sunny winter days.
Source: Peak Energy