When a 280-year-old elm tree in George and Jenna Hutchinson’s backyard had to come down, they turned it into a solar power opportunity. With their new south exposure, they worked with All Energy Solar to put up a rooftop Photo-Voltaic solar array in August 2013.
Trained as an architect, and a self-described numbers nerd, George has the data from utility bills and All Energy’s monitoring systems to keep track of the impact solar energy has on his daily, weekly, monthly and lifetime consumption and production. He estimates that 47% of their 1941 Lynnhurst home’s electrical power was created by the rooftop array in 2014.
With tax incentives and rebates that defrayed the costs of installation, George expects that his $8K initial investment will pay itself off with energy cost savings within nine years.
The first step of any climate change-based solution, George points out, is to take inexpensive steps to use less energy. Only after that are more exotic measures taken to help make a more sustainable environment.
Mid-century homes aren’t noted for insulation, or a focus on building envelope. One of the first things the Hutchinson’s did when they purchased the home in the 1980s was add R-30 fiberglass insulation to the attic, while creating a master bedroom space. They also replaced drafty old windows and an old furnace.
The new insulation was protected by a vapor retarder membrane to control moisture that naturally arises when steam from showers, cooking and winter heating — collides with colder materials and air, leading to condensation and freezing issues.
Then the fun stuff began.
The house had always had the basics of a rain garden in the yard. The Hutchinson’s expanded on the effort with a new drainage plan, largely using a sand patio foundation to capture overflow from the rain barrel set up to capture stormwater runoff. They chopped up and scored an old sidewalk to create front yard planter stones — with wire packets in gaps to hold soil — to reduce the turf grass. Native plants are combined with a vegetable garden for a pollinator friendly space.
The Hutchinson’s had composted yard waste for many years before joining the city’s new organics recycling program this year.
In 2013, they purchased an electric vehicle, which is powered by their solar array. It takes roughly 4.5 hours — or about 20 kilowatt hours — to charge the battery in the vehicle, which gives it approximately 90 miles of driving range. (It gets fewer miles in the winter, but one plus of charging it nearly every night in the cold weather is that it can be programmed to heat the cabin and seats in the morning.)
The Hutchinson’s excess solar power from its array is sold back to the Xcel grid system rather than being stored on site for personal use.
Snow has been an issue in the winter, but George created a special rake to help brush it off. The sun heat helps remove the rest, eventually heating the surface of the modules enough to help the snow slide off.
A utility provided “saver switch” system on the centralized air-conditioning unit helps reduce demand in the hottest summer months.
In September 2015, George noted that their household used 682 kilowatts-hours, and produced 491 kWh, or about 72% of consumption. Since the array was installed in 2013, they have produced 9.5 megawatts of energy.
“We can continue to simply live on the planet contributing to increasing temperatures and carbon loads — or we can do something to be part of the solution,” says George. “It’s the raindrop philosophy. A few of us making changes might not do much. But when you get a lot of us together, you get a flood.”
And the little things add up. When they replaced their 1941-era thin plywood front door, Hutchinson said, instead of getting an inexpensive model, they opted to get a high performance insulated door that would leak less energy.
It’s also about a switch in mindset. Conservation is about deciding if you need to run the dishwasher half full, he said, and if you can combine errands into one trip instead of several.
Recent homes featured in the Minnesota Renewable Energy Tour included:
- A Minneapolis Southeast Como home with a straw bale construction that is heated and powered by solar energy. This super-insulated building with a high mass thermal foundation is a training, demonstration and research site.
A Lake Minnetonka home features vertical axis wind turbines and solar PV for an off-grid electrical system.
- The Minnesota Center for Energy and Environment and the Neighborhood Energy Connection helped a Highland neighborhood family find the most cost-effective ways to reduce their energy use and become an Energy Fit Certified Home. The Sandeens cut their energy use by 50% and meet 75% of their electrical needs with a small 2.7kW solar PV system.
- A Net Zero Energy Home Case Study is featured in the Battle Creek neighborhood of St. Paul. The home has an amazing Home Energy Rating System score of 4 — the typical new construction is around 100.