The rooftop solar panel, once a badge of distinction for energy nerds and greens, is going mainstream.
While firm numbers are hard to pin down, homebuilders and industry experts say the number of newly constructed homes with a solar energy system preinstalled is surging, from as little as a few hundred units a decade ago to tens of thousands of units entering the market today.
And according to newly published data from McGraw Hill Construction and the National Association of Homebuilders, more than half of all U.S. homebuilders are expected to offer solar PV energy systems as an option in new single-family homes by 2016, up from just 12 percent in 2013.
The surge in solar-ready and solar-equipped homes, according to experts, is being driven by a variety of market forces, including rising consumer awareness of renewable energy and home-based electricity generation; a steep decline in costs for solar photovoltaic (PV) systems; the marked expansion of net metering and distributed generation; and overall rising interest in "green building."
"Solar panels are a very visible manifestation of a home's construction," Kevin Morrow, NAHB's director of sustainability and green building, said in an interview. "Increasingly, people understand what they can do for them, either by reducing their environmental footprint or by reducing their energy costs."
Experts say estimates of energy costs savings from home-based solar systems vary widely from home to home and depend on multiple factors, including local solar intensity, the size and configuration of the solar system, the amount of energy consumed by a home's electrical systems, and a home's overall "thermal envelope," or its ability to hold cool air on hot days and warm air on cold days.
Yet even with these variables, home-based solar systems have been shown to save homeowners hundreds or even thousands of dollars per year on energy bills, and single-family homes designed to maximize energy efficiency are capable of producing much -- and in some cases all -- of their electricity needs from their own rooftops.
Those kinds of pocketbook benefits are fueling a growth market in solar-ready homes nationwide, according to NAHB, with the greatest concentration of homes in parts of the sun-drenched Southwest but as far east as North Carolina and New Jersey.
In his May 9 executive order aimed at expanding solar power and energy efficiency in the United States, President Obama applauded the efforts of roughly two dozen homebuilders that have committed to building solar homes, including a private-sector program by 22 firms to build nearly 10,000 solar-equipped houses as part of an effort to advance zero-net-energy housing.
'Cash-positive from day one'
Among the top builders identified by the president and NAHB is Meritage Homes Corp. of Scottsdale, Ariz., the nation's ninth largest homebuilder by volume.
Under a partnership with SunPower Corp. of San Jose, Calif., Meritage has provided solar-ready homes to customers across its eight-state market from North Carolina to California, with applications ranging from small-scale solar water heaters to large rooftop arrays capable of powering all of a home's major systems.
C.R. Herro, Meritage Homes' vice president for environmental affairs, said in an interview that the company currently installs approximately 500 solar systems per year and anticipates that number to grow sharply over the coming years as more homebuyers reap both the environmental and financial rewards of distributed energy.
In most cases, the cost to install solar in a Meritage home is about $4 per watt, Herro said, and the financing of the systems is often rolled into the homeowner's mortgage at an additional monthly cost of between $40 and $80, depending on the size of the system.
"For most of our customers that choose to go solar, it boils down to a simple financial play, just like better windows or better insulation," Herro said. "It creates value in your home and lowers your operating costs." On average, he said, a 3.5-kilowatt solar system installed on a home that is rated as highly energy efficient can reduce total energy costs by 75 percent, according to Meritage estimates.
And when factoring for those overall energy savings, Herro said such systems can be "cash-positive from day one," meaning the additional monthly mortgage costs are lower than what the homeowner would have paid for electricity in a conventional grid-connected home.
Beyond the financial cost-benefit equation, experts say that consumers are motivated largely by aesthetics when choosing a home. Here, too, solar has advanced in ways not imagined a decade or more ago.
Now you see them. Soon you won't
Gone are the unsightly aluminum frames and hulky PV panels that used to give a solar-equipped home's rooftop an armor-plated look, or what Cerro called "the UFO on the back of the house." Modern solar technologies allow for much lower-profile systems that are color-matched to traditional roofing materials can be flush mounted to a rooftop.
"Most of our panels, you can't see them unless you climb up on a ladder and look," Cerro said.
Where homebuyers aren't choosing solar on an individual basis, developers are increasingly choosing it for them. Meritage has been a leader in such developments, called "solar standard" communities, along with PulteGroup Inc. of Bloomfield Hills, Mich., whose Phoenix subsidiary Dell Webb is building two of the nation's largest solar standard communities, with a combined 11,200 solar-equipped homes.
According to PulteGroup, every home in the Sun City Anthem and Sun City Festival communities, which are marketed to retirees and people 55 and older, includes the option of a solar system that seamlessly blends into the roof and supplements homeowners' energy needs.
"With the 55+ market trending to more energy efficient options, we wanted to provide solar as standard, not just an option," Rebecca Lundberg, vice president of sales for PulteGroup's Arizona Division, said in a statement last December announcing the Sun City home designs.
In addition to the solar systems, installed by SolarCity Corp. of San Mateo, Calif., other standard features in PulteGroup's Sun City developments include high-efficiency heating and cooling systems, compact fluorescent lighting, enhanced attic insulation, tankless water heaters, and low-water use toilets and fixtures, according to company spokeswoman Jacque Petroulakis.
To date, about half of the homes planned for the two Sun City developments have been sold, she said.
Also tapping the new solar home market, but with its own niche, is Pennsylvania-based Balfour Beatty Communities, a subsidiary of Balfour Beatty PLC of London.
Since 2012, Balfour Beatty has spearheaded the construction or renovation of solar homes on and around U.S. military installations under a long-term contract with the Department of Defense. More than 1,200 of those homes now are at least partially powered by solar arrays, according to the company, and the panels' electricity output is pooled and redistributed to meet energy demand throughout the broader communities.
The installations, which are continuing, are part of Balfour Beatty's plans to improve as many as 44,000 military homes in 26 states for active-duty members of the Army, Navy and Air Force, including major new construction and rehabilitation projects for the Army at Fort Bliss in Texas and Fort Carson in Colorado, where the company oversees a combined 7,300 homes.
Big deals in military housing
But unlike other developers that sell new homes to individuals and families, Balfour Beatty Communities is in the business of renting homes to soldiers, sailors and airmen. As such, all of the homes remain owned by a public-private partnership, which also is responsible for providing most utility services to the residents, including electricity.
"We have some advantages when testing new technologies that reduce energy in that we own and operate the homes and are able to view the energy consumption for nearly every home," said Tabitha Crawford, a Nashville, Tenn.-based spokeswoman for Balfour Beatty Communities. "One of those advantages is we can see very quickly what is working and what's not working."
What has worked exceptionally well, Crawford said, is rooftop solar panels, which the company has now installed on many of the 4,700 homes it manages at Fort Bliss and the nearby White Sands Missile Range in New Mexico. When fully built out, Crawford said, those panels will form the backbone of a 13.2-megawatt solar power system that feeds electricity into a shared grid for all of its duplexes, townhomes and single-family homes on the base.
The Fort Bliss solar systems are also leased from SolarCity, which itself has invested $1 billion in its SolarStrong Initiative to power 120,000 military houses using solar technology.
Balfour Beatty agreed to buy the power from SolarCity at a fixed rate with escalators over a 20-year period, and the panels' output is expected to meet 26 to 38 percent of the Fort Bliss homes' electricity demand, Crawford said.
Balfour Beatty is negotiating the terms of a similarly sized solar project for its housing units at Fort Carson near Colorado Springs, Colo., but Crawford could not disclose details of that proposal, which still awaits formal approval. Fort Carson is already home to the military's largest solar installation, a 2 MW utility-scale PV array covering 12 acres of a former landfill.
Both Fort Carson and Fort Bliss have been designated by the Defense Department as facilities that are trying to achieve "Net Zero" status, meaning they must meet stringent targets for conserving electricity, water and waste.
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