Harnessing power from the sun was, until recently, the providence of those living off the power grid or those with deep pockets.
But there is a modestly-sized house on West Geyser Street in Livingston that breaks the mold for a solar powered house. The photovoltaic system produces about 375 kilowatt hours per month. That’s about half of what an average household uses in 30 days, but enough to run the Geyser home, according to Conor Darby, general manager of Independent Power Systems, which is installing the system.
By Peter Vandergrift, Enterprise Staff Writer
“Solar came from a backwoods beginning, but has become mainstream,” said Darby, whose company specializes in solar and wind power generation systems.
Now, companies like Microsoft and Google use solar energy to help power their office buildings, he said.
Darby’s brother Sean renovated the house a couple of years ago, and the two decided to try to make the house a “net-zero” house.
A net-zero energy home, at a minimum, supplies the power grid an annual output of electricity equal to the amount of power purchased from the grid. In many cases, the entire energy consumption of a net-zero home can be provided by renewable energy sources like solar or wind, Darby said.
Sean also put in energy-efficient electric appliances.
The house is owned by the Darby brothers’ parents and is lived in only about six months a year, Darby said.
On Tuesday, Darby and electrician Gary Brumley installed the second set of solar panels on the roof of the 800-square-foot home. The panels are tied to the house and the energy grid so any extra energy not used to by the appliances or baseboard electric heat flows into the power grid. Those kilowatts are credited to the house.
“The meter runs both ways,” said Brumley.
In the past, grid-tied system were the minority of solar projects IPS installed. But as solar has become more efficient and renewable production of energy has more trendy, 75 percent of Darby’s 30 or more installation jobs last year were for homes tied into the grid.
How the system works is not complicated, Darby said.
When photons in sunlight hit the solar panels on the home’s roof, they are absorbed by semi-conducting material, such as silicon. Negatively charged electrons are knocked loose from their atoms and flow through the material to produce electricity.
The current flowing from the panels is direct current (DC), like battery current, and must flow through an inverter that changes it to the alternating current (AC) found in homes.
“I came from a DC background, while Gary came from an AC background,” Darby said.
Brumley was a home electrician in Colorado but became interested in doing something different and started working with IPS, which has offices in Bozeman and Boulder, Colo.
With the two 20-foot-long solar panels in place, Brumley carefully connected some wires in a junction box.
“Three hundred and sixty volts in DC is lethal,” he said.
The panels should be installed at a 45 degree angle in Montana to receive good sunlight on fixed systems like that of the Geyser house, according to Brumley.
Some pedestal-mounted solar arrays will follow the path of the sun, maximizing efficiency, but these are more expensive — about $3,500 more per mount, Darby said.
The Geyser project cost $24,000, but with an energy grant and tax credits adding up to $9,500, it will pay for itself in 25 years at current power prices, Darby said.
“The next 25 years could see much steeper prices,” which would shorten the payoff period, he said.
Having solar capability increases the resale value on a home, and many new subdivision homes in Colorado and California have solar panels or the hookups for panels for future installation, said Darby.