When does solar or other alternative energy make sense for your home? Are you looking for lower utility bills? Concerned about our effect on the planet from burning fossil fuels? Would you like more energy independence so you’re less inconvenienced by downed power lines, blackouts, brownouts, or other utility disruptions?
Here are good reasons for considering solar and alternative energy:
- Cut your electric bill. Let the sun, earth, or wind help with the bills. Most alternative energy systems supplement the fossil fuels your house uses. Less purchased fuel means more money in your pocket.
- Help to save the environment. Using more renewable energy means using less electricity generated by burning fossil fuels, which emit harmful greenhouse gases.
- Improve your home’s resiliency during power outages. When storm-related power outages occur, a home with photovoltaic (PV) panels can generate its own electricity.
- Improve your home’s green value. The resale value of a house increases when it has clean energy features like a PV system or a geothermal heat pump.
- Take advantage of state and federal incentives. There are a surprising number of incentive programs for energy-saving improvements that include renewable energy upgrades—rebates, low-interest loans, tax breaks, and more. For up-to-date details, visit www.dsireusa.org.
How to Reduce Your Carbon Footprint
Today we have more options for harnessing renewable energy than ever before. And energy-saving upgrades like solar panels and geothermal heat pumps are becoming more affordable to install, too. But no matter how our homes’ energy is generated, it’s important to reduce consumption by employing energy-efficient practices.
In 2018, U.S. residential utility customers used on average 10,972 kilowatt-hours (kWh) a year. That works out to about 914 kWh each month. Residential customers in Tennessee used the most electricity each year on average 15,394 kWh. While residential customers in Hawaii used the least each year on average: 6,213 kWh.
Here’s what consumes the most energy in your home:
- Cooling and heating: 47% of energy use
- Water heater: 14% of energy use
- Washer and dryer: 13% of energy use
- Lighting: 12% of energy use
- Refrigerator: 4% of energy use
- Electric oven: 3-4% of energy use
- TV, DVD, cable box: 3% of energy use
- Dishwasher: 2% of energy use
- Computer: 1% of energy use
A cost-effective alternative energy system does not need to provide all your home’s energy needs. Understanding that concept will help you decide which system is right for you, and what size makes the most sense.
Alternative Energy Sources: Solar, Geothermal and Wind
With a massive energy-emitting battery in the sky—the sun—it’s amazing that we use so little of the energy that comes our way. Today, solar energy accounts for about 1.6% of U.S. electricity generation and there are more than 1.4 million solar panels in use.
To consider retrofitting your home with solar power, many variables must be considered:
- Do you live in a sunny area? While the sun hits Minnesota as well as Arizona, the power generated in Arizona will be much greater based on the intensity of the sun and how many sunny days the area experiences. Solar systems do not produce as much power on foggy or cloudy days as on clear, sunny days.
- Are the energy bills higher or lower in your area? When electrical power or gas is cheaper, the installation of solar arrays becomes less financially attractive. If energy rates are higher, solar investment becomes a better deal.
- Are rebates and incentives available? Local governments and utilities may encourage solar retrofits to decrease the draw on the energy grid during times of peak use, such as blazing hot days when air conditioners are turned up.
- Does your utility offer a grid-tied option? While the original solar energy systems relied on large banks of expensive batteries to store the energy produced during the day to be used at night (when no solar energy is generated), the current model is to feed your excess energy production back into the power grid during the day, then draw from the grid at night. How much you are paid for the energy you feed into the grid makes a big difference in your overall energy savings. If your area has no grid-tied option, you can encourage the utility to start one up.
Solar Power: How a PV System Works
Solar arrays (a collection of solar panels) generate energy by absorbing light from the sun. An inverter transforms the DC (direct current) energy produced by the panels into the AC (alternating current) power that your house runs on. General guidelines call for 1 kilowatt, or 1,000 watts, per 1,000 square feet of house area, but you should work with your contractor to determine the right size for your home for solar heating and cooling.
There are two main locations for home solar system installation:
Rooftop: For neighborhood homes, a rooftop solar array makes the most sense. But some communities consider rooftop solar arrays to be eyesores. In that case, a new generation of solar-power-generating roofing materials may be considered. They look like tile or slate but are actually solar energy receptors. (It’s not hard to imagine a future where window glass and even house paint contain micro solar energy receptors to help power a house.)
Stand-alone: For larger properties with more expansive yards, a metal-framed stand-alone system might be appropriate. The advantage is that the panels are not dependent on the slope of the roof or the direction the roof is facing. The panels can be tilted to take maximum advantage of the sun’s rays. One innovation is an array that moves like a sunflower to follow the arc of the sun across the sky.
Cost: With the many variables involved—the size of the home, insulation, the efficiency of appliances, geographical location, rebates, and incentives—the cost of a home solar system is hard to determine. You can expect to spend more than $20,000 on such a system and expect to recoup the cost in 10 to 20 years.
DIY Projects to Consider: Even if you’re not ready to install a whole-house solar array, smaller projects can produce solar power for specific tasks. A roof-mounted solar water heater may be within the budget and within a homeowner’s skill level. Costs could run about $5,000, and less with rebates and incentives. Solar-powered landscaping lights add ambiance without running up the electric bill.
When to Hire a Pro: Many companies have emerged over the years that not only design and install solar systems but also help with permits, financing, and the tie-in to the utility grid. In some cases, you pay no money down, and your monthly payments for the system are lower than your current utility bills. Upon paying off the system, you own it and reap the benefits thereafter.
Another alternative energy option, geothermal, relies on an extremely consistent source: the earth itself. More specifically, geothermal systems take advantage of the consistent temperature of the earth at a depth of at least 8 feet—about 50 degrees F.
Geothermal systems work by integrating heat pump technology with the constant moderate temperature of the earth to supply a home with heating and air conditioning. Like conventional heat pumps (including refrigerators and portable air conditioners), geothermal (aka ground source) heat pumps are powered by electricity and work by pumping a refrigerant compound through condensing and evaporative cycles to move heat from one source to another. But geothermal systems use much less energy all year round, no matter how hot or cold it is outside. You can expect a geothermal heat pump to be twice as efficient as a top-rated air conditioner, and nearly 50% more efficient than the best gas furnace.
Unfortunately, the energy-saving benefits of ground-source heat pumps come at a high installation cost. The “ground loop” in a geothermal system consists of long lengths of plastic pipe that can be placed horizontally, in trenches, or vertically, in deep holes. Soil conditions and available land determine which type of ground loop is used. Either way, the installation work can easily push system costs to $20,000 or more. But once the installation is complete, these systems usually deliver many years of low-cost, trouble-free performance.
Wind Power for Homes
Like other alternative energy systems, wind-generating equipment continues to become more sophisticated and less expensive. Wind accounted for about 6.5% percent of energy produced in the United States in 2018. And you don’t have to live in a wind tunnel. Even light winds of eight miles per hour can generate power. But a windier area will generate more energy. Most manufacturers suggest that at least an acre of land unobstructed by trees or structures surround the turbine for optimal performance. Obviously, a turbine between tall buildings would not be effective.
How Home Wind Power Works
In a typical residential setup, a wind turbine is mounted on a tall tower. Turbines are not installed on the roof, as they would cause your house to vibrate. As with solar power, an inverter converts the DC energy generated into the AC power your house runs on. Concerns about home turbines range from aesthetics to noise to bird deaths. Yet some users claim the noise is no greater than that of an electrical transformer.
Cost: Like solar, a wind-powered system depends on weather and location. More wind, more power. One family near Lake Erie in Ohio, for instance, erected a 45-foot-tall, 1.8kilowatt wind turbine system for $15,000. That includes the turbine, the tower, the foundation, installation, inverter, permits, monitoring systems, and tie-in to the power grid. Such a system provides up to 400 kWh of energy, about half the family’s needs. Such a system could pay back in 12 years.
DIY Options: Because of the scale of the equipment, erecting a wind turbine sufficient to power most or all of a home’s power needs is not considered a DIY project.
Bottom Line: Even if a wind turbine is not right for your home, you may be getting some of your electricity from a wind farm. At least 26 states require a percentage of energy to be produced from alternative, renewable sources.
How to Make Your Home More Energy Efficient
- Air conditioning and heating—As noted above, these account for almost half of your home’s annual energy use. When it’s time to replace your system, choose the highest efficiency you can. And make sure your current systems are maintained. Check the filters and make sure the ducts in the attic are not leaking.
- Appliances—When it’s time to replace your appliances, choose models with the highest energy efficiency ratings. We now have 98-percent-efficient boilers, furnaces, and tankless water heaters. Energy Star programs push for more efficient appliances, fixtures, and heating-and-cooling equipment.
- Windows—Make sure your windows are in good working order. Do they close properly? Are the seals compromised? If window replacements are in order, choose the most energy-efficient models available.
- Lighting—Replacing incandescent bulbs with LEDs is the easiest, most cost-effective way to minimize utility costs.
- Phantom Power Drain—Beware of “phantom power” drains, which stem from devices that are using electricity even when they’re off, like microwaves, printers that are plugged in, etc. Try plugging devices into power strips and keeping those power strips turned off when the appliances aren’t in use.
- Energy Audit—Consider hiring an energy auditor to test your house for energy leakage. They can tell with various testing methods where your house is letting in the cold or hot outdoor air, depending on the season.