Home Solar Energy

Solar power has come a long way in recent years. Newer, more efficient solar technology allows homeowners to reduce their use of electricity and fossil fuels without filling the backyard with solar panels. Thanks to tax credits and the ability to sell power back to your electric company, an investment in solar can pay for itself over the long run.

How Solar Cells Work
The principles of solar power were built upon the work of 18th century French physicist Antoine-Cesar Becquerel, who discovered that changing the pressure in a piece of metal produced an electrical current. In 1883, Charles Fritts built the first true solar cell, but the materials he chose, gold and selenium, only allowed an efficiency of 1%.

American inventor Russell Ohl replaced the selenium and gold with silicon in the 1940s, creating the first modern solar cell with an efficiency of 5%. Further refinements have increased the efficiency to 20%, which is what allows solar cells to power a home.

So how does solar power work? In the simplest terms, when a ray of sunlight hits a material, there's a chance that some photons will be released. These photons contain an electrical charge. Solar cells capture these photons and force them to move in a single direction, which produces an electrical current. This current can be tapped immediately, as it is in a solar-powered calculator, or used to charge a battery, as it is in the solar-powered walkway lamps available at home centers. The larger the solar panels, the more power you can generate.

Adding Solar Power to Your Home
Tapping solar energy once meant installing huge photovoltaic panels to the roof or backyard. Those panels are still available and they're among the most efficient choices, but a newer, more architecturally pleasing option is solar shingles. Apart from some extra shine, these look like regular asphalt shingles and they turn your entire roof into a giant solar power plant.

Whether you use panels or shingles, the solar power is collected and sent to a solar junction box, where it's converted into current to power your home. While the sun shines, you'll get free power, and most states will allow you to sell any excess power that you generate back to your utility company, which will greatly lower your bill. The solar junction box works alongside a standard electrical hookup to provide power at night or when it's cloudy.

Some state-of-the-art systems incorporate large rechargeable batteries to keep the current flowing even after sundown, but these can't provide enough power for all of our modern creature comforts, such as air conditioners, computers, refrigerators and TVs. For that reason, a solar-only home still isn't possible, but continued improvement in solar cell and battery design could make it a reality within the next 50 years.

You can also use the sun to generate hot water. A solar thermal system uses panels to collect heat rather than electricity. In warmer parts of the country, the water is heated directly by the panel and sent to a hot water tank. In areas with below-freezing temperatures, an antifreeze solution is pumped into the panels. The solution is then pumped to a heat transfer unit to warm the water.

This cuts down the amount of oil or gas needed to generate hot water in your home. You'll still need a gas or oil hookup for cloudy days, but you may find that your use of these fossil fuels drops dramatically.

Passive solar heating can also be incorporated into the design of a new home or a home addition. A good example of this is a sun room or conservatory with glass walls. By using materials that collect heat during the day and radiate it at night, such as brick or stone, the sun room can help to raise the overall temperature of your home, which means less work-and less energy consumption-for your furnace.

Out in the yard, almost anything that runs on electricity can be powered by the sun. There are those solar walkway lights, as well as solar wall lights and security lights. You can warm your pool or hot tub with a solar heater, and the first solar lawn mowers are making their way to US markets, though their lengthy charge times and short battery life make them most suitable for smaller yards.

Savings Build Over Time
Converting to solar involves some steep up-front costs. A typical home electrical system costs around $20,000, including the solar panels and solar junction box. Shingle systems can be more expensive, depending on how much roof you need to cover.

It can take some time for the system to pay for itself, depending on your energy use and costs. It's rare for consumers to get a check from the local utility for producing energy, but it can happen in sunnier parts of the United States. Most homeowners will see their savings build each month, in the form of lower utility bills.

The federal government also offers tax incentives for installing solar systems. As part of the Economic Emergency Stabilization Bill of 2008, all homeowners can deduct 30% of the cost of solar equipment from their income taxes. The $2,000 cap is eliminated for solar systems installed after December 31, 2008, and taxpayers who use the Alternative Minimum Tax are eligible for the credit. You may also be eligible for tax deductions at the state and local levels.

A solar pool or hot tub heater will cost a few hundred dollars, while a solar thermal system costs a few thousand. These will pay for themselves within a few years in annual energy savings.

While solar energy hasn't been perfected yet, it's come a long way in terms of efficiency and performance. As energy prices continue to rise, adding solar to your home is a way to go green with long-term savings benefits.