With Boulder's much-touted "300 days of sunshine a year," solar power seems like a no-brainer for residents who want to green their home energy. Once financially out of reach for most homeowners, solar is becoming more accessible due to decreasing technology costs and incentive programs that help offset the cost of solar systems.

But despite solar's growing popularity and affordability, it isn't the only green energy option out there, nor should it be the first one residents consider, say local energy experts. There are numerous alternatives to solar and, luckily, numerous sources of information to help homeowners choose the right ones to fit their energy needs.

Eric Doub, CEO and founder of Boulder's EcoSmart Homes, says that a homeowner's first step should be a professional energy audit. Among other things, an energy auditor will check your home for air leaks and inadequate insulation and assess appliances for energy efficiency.

To obtain an audit, homeowners can contact the county's EnergySmart program, which offers homeowners subsidized energy audits for $120. Afterwards, an adviser helps the homeowner find qualified contractors to do the recommended work and guides him or her through the various incentive programs and financing options.

Alternately, homeowners can hire a home-performance contracting company, such as EcoSmart Homes, which will perform both the energy audit and the necessary upgrades. Either way, "that assessment is vital," said Julie Herman, executive director of the Boulder Green Building Guild. "It can help you understand where you're wasting energy and allow you to prioritize what steps to take next."

Those steps usually include a slate of energy-efficiency measures to reduce energy use (and loss) in the home. "The cheapest unit of energy is the one you don't use in the first place," Doub said.

That's why he and other experts suggest tackling this "low-hanging fruit" first. For instance, EnergySmart auditors switch out incandescent light bulbs for compact fluorescent ones and install energy-saving showerheads as part of the initial energy audit. Other efficiency recommendations may include air sealing and adding insulation to crawl spaces and attics, recommissioning or replacing inefficient appliances and mechanical systems, and installing a programmable thermostat to regulate heating and cooling.

In addition to lessening greenhouse gas emissions and lowering utility bills (adding insulation and air sealing can reduce heating and cooling costs by up to 20 percent, and a compact fluorescent bulb can save up to $40 in electricity costs over its lifetime), these energy-efficiency measures can make a home healthier and more livable.

"Most of what we do is actually driven by comfort concerns," Doub said. "Say you've got a room above the garage that you can't use because it's too hot or too cold. Fixing drafty windows and adding proper insulation can make it comfortable."

Once you've made your home as energy-efficient as possible, you can move on to investigating greener sources of power. "Focus on reducing your energy demands first, then let those alternate sources of energy be like the icing on the cake," Herman advised. In addition to solar panels, two emerging eco-energy sources are ground-source heat pumps and small wind turbines.

Although the geothermal energy from a ground source heat pump isn't technically considered a form of "renewable energy," it's still an eco-friendly way to heat and cool your home, said Laura Hutchings, CEO of Populus, a sustainable design consulting company and administrator for Boulder's residential EnergySmart program.

With a ground source heat pump, a network of piping is laid underground. Liquid refrigerant is pumped through the pipes, where it absorbs heat from the ground. The refrigerant is pumped back up and compressed, increasing the heat energy temperature to approximately 120 degrees, which is then used to heat a home's interior or to produce hot water.

What makes this technology so eco-friendly is its high level of efficiency. Monte Schmidt, owner of geothermal company Blue Valley Energy, explains that, for each watt of electricity used, a heat pump generates about four watts of heat energy, making it up to 400 percent efficient. In contrast, electric heaters and natural-gas furnaces top out at around 100 percent efficiency. And, because the systems utilize off-peak power, geothermal can help smooth out power-grid peaks and valleys.

This efficiency can result in substantial savings. Schmidt said that one customer who switched from propane to geothermal heating saved almost $5,000 in one year. And geothermal can be especially cost-effective when paired with solar power: "I got a call just this week from a client," Schmidt said. "We put in a geothermal system for him years ago, and he recently added solar panels and extra insulation. Now his house is running at net zero energy use."

Small wind is a trickier subject. Although the cost of commercial wind energy has gone down significantly in recent years, the technology generally isn't economically feasible at the residential level. At least not yet.

"You can do small wind in Boulder County, but it's difficult," said Brad Queen, energy division director at the Center for ReSource Conservation. Not only does the investment take longer to pay back, but the logistics pose a problem as well. "To get good wind, you need to get the turbine up pretty high, which can be a problem in a residential neighborhood," he explained. "And you can't just bolt the turbine to your roof — that will cause damage to the roof and probably still won't be high enough anyway."

However, Queen said that small wind does have its place. "It can make sense if you have an off-grid house up in the mountains where there's lots of wind at night, especially if you couple it with solar panels that produce energy during the day."

"As the technology improves and the small turbines are better able to handle our dramatic wind storms, I think small wind will become more popular," Hutchings said.

But despite these recent and potential technological developments, the experts reiterate that reducing your energy demands should come before seeking out alternate sources of energy.

"Solar, ground source heat pumps, small wind turbines — these can make sense in the long-run, but you have to make sure that the design is solid," Queen said. "And you should only pursue them after you've exhausted all the avenues for energy conservation."


Financing green energy

"With all the incentives right now, there's a lot of money out there to get back," Herman said. Here are just a few of the loans, rebates and other incentives out there to help fund your green energy project. Consult your energy auditor for a more comprehensive guide.

• The federal government offers a personal tax credit for up to 30 percent of the cost of installing solar water heaters, solar panels, small wind turbines, geothermal heat pumps, and other green technologies.

• EnergySmart offers rebates of up to $1,000 and low-interest microloans of up to $5,000 to Boulder County residents to help pay for home-energy upgrades such as air sealing, adding insulation, replacing windows, and purchasing high-efficiency furnaces and water heaters.

• Xcel Energy's Solar Rewards offers rebates to customers who install photovoltaic panels.

• Longmont Power & Communications offers matching grants of up to $500 to residents who implement qualified energy-efficiency measures such as air sealing, adding insulation, and replacing furnaces, refrigerators and water heaters with more efficient models.