I heard from readers when I wrote about the pioneering solar home that Lexington architect Richard Levine built for himself in the 1970s and recently upgraded with new technology.
I heard from more readers when I wrote about Warren County's new "net-zero" school, designed to generate as much power as it uses.
Many readers wanted to know this: How could they use solar power and innovative design to help the planet and lower their utility bills?
As solar technology gets better and cheaper, it is becoming a viable alternative for more Kentucky homeowners, said Andy McDonald, director of the Kentucky Solar Partnership, an advocacy organization in Frankfort. Options range from solar-powered water heaters to super-insulated "passive" homes.
Because Kentucky isn't sunny year-around, McDonald said, "Many people believe that solar is not viable here, but that isn't true. Germany leads the world in solar energy, and Kentucky has better solar resources than Germany does."
The difference, McDonald said, is government policy and incentives. The United States lags many countries in policies promoting renewable energy, and Kentucky lags many states in incentives. But help is out there.
Since 2004, Kentucky homeowners have been able to hook solar generators into their local utility, getting credit for power they feed into the grid to offset power they draw at night and on cloudy days. It is possible for homeowners to break even — and even earn a profit if their utility's power comes from the Tennessee Valley Authority.
The federal government since 2005 has offered tax incentives for installing solar and other renewable energy systems. The state also offers some incentives, and the Mountain Association for Community Economic Development has flexible loans for some systems installed in Eastern Kentucky.
The most popular systems are solar water heaters, like the one Dave Kollar had installed in his Madison County home two years ago. The water heater is powered by two small solar panels on his roof that charge batteries. When the sun isn't shining, the water heater can run on regular current.
Solar water heaters in Kentucky typically produce about 70 percent of a home's hot water over the course of a year.
Kollar said the system cost him about $5,000, after incentives. With what he is saving so far, he estimates it will pay for itself within 12 years. "For me, though, that's just part of the equation," said Kollar, chief engineer for Fox 56 television.
"I don't know that we're saving the planet, but fossil fuel is a finite resource and it seems silly to waste it," said Kollar, who also supplements his home's furnace with a wood stove. "Besides, I didn't want to go through another ice storm without hot water and heat."
For homeowners wanting to do more than heat water, there is one key thing to understand: Success is not so much about how much power your solar system can produce; it is about how energy-efficient you can make your home so it uses as little power of any kind as possible.
The first step toward lower utility bills is weatherizing an existing home or designing a new home to minimize energy loss and take advantage of natural sunlight.
Basic design principles include having a home's long axis facing south, with windows that let in winter sunshine but are shaded against summer heat. Likewise, minimize windows on a home's west side, which gets a lot of summer sun, and the north side, which catches winter winds, McDonald said.
While Kentucky may be behind other states in solar incentives, it is ahead of most when it comes to green building design. Levine, who last year received a "pioneer" award from the American Solar Energy Society, runs an architecture practice that is bringing European "passive" home design to Kentucky.
So-called passive homes are so heavily insulated that little energy is lost. They use only about 10 percent of the energy needed to heat and cool a well-built conventional home. Because these houses are so airtight, they are equipped with special ventilators that bring fresh air in from the outside with minimal heat and cooling loss.
Levine's firm, CSC Design Studio, is designing five passive "net-zero" homes for Kentucky Highlands Investment Corp. intended for sale to middle-income people. The first is under construction near Williamsburg.
CSC also recently designed a net-zero home for a client who will begin construction in July along the Kentucky River, said Michael Hughes, an architect who works with Levine. Power needed for these passive homes will come from solar panels on the roof.
Passive homes can cost as much as 25 percent more to build than conventional homes, but Hughes thinks prices will fall as more builders learn how to build them and domestic companies step in to compete with European manufacturers of super-insulated doors and windows. "I think it's the future of home building," Hughes said.