New solar maps help homeowners and installers

Nov 3, 2008 - McClatchy-Tribune Regional News - Matt Nauman San Jose mercury News, Calif.

Innovations in online mapping are contributing to the rapid growth of solar energy. The high-tech tools benefit everyone from homeowners and solar-panel installers to the developers and financiers of large-scale power projects, industry experts said at a recent solar conference here.

Google Earth allows aerial views of rooftops that help installers prequalify solar-system buyers. Using Google Maps, San Francisco offers residents and businesses a chance to see the city's solar hot spots. And a new map from 3Tier, a Seattle company, provides a detailed study of how much sun shines at any spot in the Western Hemisphere.

"It's fantastic," said Lyndon Rive, chief executive officer of SolarCity, the state's largest solar-panel installer based in Foster City. "It makes our business a lot more efficient."

And with the credit crunch and the perilous economy, precise solar maps will be increasingly important as investors seek assurance that deals will be profitable, said Kenneth Westrick, founder and CEO of 3Tier, a Seattle company that just released a solar-irradiation map with information as broad as a continent and as specific as the house down the street.

Here's a look at some new or emerging solar-mapping technologies and applications:

It's a solar world

Released last month, 3Tier's solar map of the Western Hemisphere provides a detailed view of where, when and how intensely the sun shines in North and South America.

"This is really the tip of the iceberg," Westrick said. "The map is the paint on house. It's what you really see, but what's behind that is a very rich data stack."

That's perhaps an understatement. 3Tier had to buy a supercomputer, he said, to process 11 years of solar data captured every half hour at three-kilometer resolution from satellite images. Company spokesman Todd Stone called that type of detail "a technological breakthrough."

While not intended as a consumer product, 3Tier's map does allow a user to see how much sunshine his or her home gets. The product's real audience is developers of large-scale solar installations and the entities that finance those projects as they need the exhaustive day-by-day, half-hour-by-half-hour solar data to verify the best locations for their facilities.

Better information means quicker decisions, Westrick said, saving money and bringing renewable-energy resources into production more quickly.

"What used to take six months or a year to evaluate, now maybe you can do it in six weeks or six days," he said. "That's really going to move this process forward."

3Tier's map is available online at firstlook.3tiergroup.com/solar. (Access is free, but registration is required.) The company sells customized versions to project developers for $4,000 to $7,000, and makes the bulk of its revenue selling energy-generation forecasts based on its solar and wind maps, Westrick said.

Finding the right location is crucial, he said, because a move of just a few kilometers can mean more or less sunshine. "Over a period of years, there's going to be a huge difference in how much power is going to be produced."

The company plans to create solar maps of the rest of the Earth in the next year or so.

Installer's best friend

With the help of Google Earth, an installation company can quickly tell you if your home is in an appropriate location for a solar system and how big a system your roof can handle.

Borrego Solar, based in San Diego County, will do more than 200 solar installations this year, including homes, businesses and schools. A 165-employee company, Borrego has six locations, including San Jose, San Francisco and Berkeley, said Aaron Hall, its CEO and chairman.

Using Google Earth maps allows his staff to do much even before a homeowner signs up for a system, and before the first visit to the home takes place.

"We can look at your property and right away tell you, 'Oh, you have 15 trees around your house,' " Hall said. "You can get a lot of quick information that's not just Web-site generic information."

Further advances are coming soon, he said. Currently, Borrego and many other installers rely on hand measurements of roof dimensions. When they're off, even slightly, it means re-engineering a system on the fly and having to tell a homeowner that the system will look slightly different than what had been anticipated.

Rive said SolarCity already uses Google Earth to measure roofs. That, and an analysis of a customer's electric bill, allows his company to provide a "99 percent accurate" estimate of how much energy a solar system can produce, he said. Touring a solar city

San Francisco's solar map provides a virtual look at the sunny side of that city. Created by CH2M Hill for the city and county of San Francisco as part of the Department of Energy's $5 million Solar America Cities program, it provides frequently updated information and an interactive experience.

"In San Francisco, we get a lot of people who say, 'San Francisco is too foggy. Does solar even make sense for us?' We thought, wouldn't it be great to not only show their solar assessment, but also show them some of their neighbors who had done solar," said Johanna Partin, renewable energy program manager for the city's department of the environment.

The map, at sf.solarmap.org., shows many of the city's residential, commercial and municipal solar installations. It features daily reports from the city's 27 solar monitoring sites, includes photos and stories from some of the solar-system owners, and offers updated statistics showing that 871 solar systems are generating 5.9 megawatts of power in San Francisco.

San Jose also is one of 25 Solar America Cities, and will create a solar map that also includes energy-efficiency efforts in various neighborhoods, said Mary Tucker, the city's energy program manager in the environmental services department.

The San Francisco map allows homeowner to determine if their home is appropriate for solar, how much it might cost, what incentives are available and even provide links to installers, said Steve Herrmann, client service director for CH2M Hill, a Denver-based engineering/construction company that won the Energy Department contract to administer Solar America Cities activities.

"Today, when you call up (a solar company) to figure out if you have any solar potential on your roof, they roll out a truck, get out the ladder and the guy climbs on your roof," he said. "We think this technology improves on that."

Contact Matt Nauman at (408) 920-5701 or at mnauman@mercurynews.com.