More homeowners are creating a solar flair by installing sunlight-capturing panels or shingles on their homes. Powered by photovoltaic cells, the future for solar energy has never been brighter, says Dan Whitten, Solar Energy Industries Association (SEIA) spokesperson, based in Washington, D.C.
"The case for solar has become increasingly strong as the United States' energy system has evolved," he says. "Solar energy is becoming more efficient to deliver, with fuel from the sun that is free, renewable and sustainable."
Since the dawn of civilization, humans have tried to harness the energy of the sun to warm their homes. But it wasn't until the 1970s -- through the technological development of photovoltaic cells fabricated into panels -- that solar energy began its modern residential ascension.
Photovoltaic (PV) or solar cells convert sunlight (or photons) directly into electricity (or voltage) that can be used as power. PV cells were initially manufactured using silicon (found in sand) after scientists discovered that the element released an electrical charge when exposed to sunlight.
"Today's solar energy isn't your grandparents' solar panels from the '70s. The last three years have seen tremendous growth in residential solar energy, thanks to technological advances," Whitten says. "In 2016, according to our data, 1 million solar units had been installed in the United States. In 2018, that number jumped to 1.7 million."
In 2020, every new construction project of single family homes in California will be required to have solar units built onto roofs. And while California is the first state to pass this mandate, it won't be the last to do so, says Jim Turner, spokesperson for RGS Energy, a Real Goods Solar Company, based in Denver. RGS Energy was one of the first solar panel installers in 1978 and, to date, has installed more than 25,000 solar power systems across the country.
"In 40 years, we've seen the cost of solar energy fall from $100 to $4 per kilowatt," Turner says. "The technology is such that solar modules have not only gotten smaller, but more efficient."
Solar panels that are rack-mounted are still the most prevalent way to capture solar energy. Panels may be ground-, rooftop- or wall-mounted, with a fixed mount or adjustable mount fitted with a solar tracker to follow the sun across the sky.
Nearly 10 years ago, Dow Chemical Company developed the first viable solar shingle system, called the Powerhouse. A solar shingle system is intermingled with conventional roofing materials and designed to combine the performance and protection of a conventional asphalt roof with an integrated photovoltaic system that powers the home.
RGS Energy has entered into an exclusive agreement with Dow to lead all commercial activities for the Powerhouse shingle system, including supply chain management, installation and warranty responsibilities. The third generation of Powerhouse shingles is expected to hit the market later in 2018, and Turner says it is a cost-effective option only with new roofing projects.
"Panels have become less clunky and have lower-profile rails, but some people want the seamless look that a solar shingle can provide," he says. "The more technical part of a solar power system is the efficiency with which the solar energy is converted into electricity."
Solar cells generate direct current (DC), giving off an electrical charge that flows in one direction into an inverter. The inverter converts the solar DC power into alternating current (AC), which is the prevalent electrical system used within homes.
A net energy meter keeps track of the all the power a home's solar system produces. Any solar energy not used simultaneously with production goes back into the electrical grid through the meter. When a home's solar power system is producing less than a user's needs, the home will consume electricity from the grid as normal. A home's utility bill will reflect the net consumption and provide a credit for any excess solar energy generated and not used during a given period.
But solar power systems don't always have their day in the sun and are reliant on exposure to direct sunlight, Whitten says. "Installing a solar power system in a home is as individual as the homeowner itself," he says. "Begin discussions with a reputable solar power system installer, and the company can tell you if your home is a good candidate for collecting solar energy and pricing."
When consulting a local, reputable solar company, consider the following:
-- Location, location, location. Check to see if your home is a good candidate for a solar energy system. Homeowners associations and local governments might also have restrictions about the types of solar power systems allowed. An unobstructed, sunny southern exposure yields high solar energy output.
-- Maintenance. Solar cell modules generally come with an industry-standard 20-year warranty, which guarantees panels will produce at least 80 percent of the rated power after 20 years of use. Ongoing maintenance includes keeping solar modules free of debris and snow.
-- Cost and incentives. Contact a reputable solar installer for a cost analysis to determine whether to lease or buy solar panels or solar shingles for your home. Factors are determined by weather, how a home is situated on a property and the amount of energy a household uses. Check into local and federal tax incentives available to homeowners that install solar power systems.
Advances in solar power technology and increased manufacturing scale have reduced costs, increased reliability and created greater efficiency of photovoltaic installations, Whitten says. "There are visionaries in the solar industry that dream of the day when our homes and automobiles will all be powered by the sun with zero emissions into the atmosphere," he says. "The share of solar energy is only going to grow with time."
A Place in the Sun
-- SEIA.org: Scroll to the Solar Energy Industries Association's "Where It's Happening" section and click "Explore the Map" for a list of reputable solar companies and statistics in your state.
-- RGSEnergy.com: Click "Solar Pricing" to receive a quote on solar power system options for your home.