The Power of the Sun

An article on solar energy from an online newspaper was a real eye opener.It seems that even though the sun rays shines on everyone and everything-it does not fall equally on them. The development of solar power has been hindered due to this fact of reality. Depending on where exactly in the city you live — the same array of photovoltaic solar panels can produce enough electricity to power your house with watts to spare, or barely enough to reduce your electricity bill. It all boils down to the exact amount of sunlight that hits your roof.

An engineering company in San Francisco, CH2M Hill is now joining hands with the U.S. Department of Energy to provide Internet solar maps of 25 American cities, using Google Earth technology to chart the precise solar potential of neighborhoods, literally measuring the sun's rays from rooftop to rooftop. The company has just finished mapping all of San Francisco, allowing residents to enter their address and take the solar measure of their own home. "People in San Francisco think we don't have any solar potential,' says Gavin Newsom, the city's deep-green mayor. "But the map implies that a lot more sun energy can be tapped."

CH2M Hill has already labeled all 925 existing solar systems throughout San Francisco, including commercial sites, government sites and the handful of residential sites. But the most interesting part comes when you enter in an address — any address in San Francisco — into the website. The camera zooms in to your rooftop collecting data on the size of the roof, its estimated solar energy potential, the estimated electricity that could be produced and the utility bill savings, as well as the amount of carbon savings that can be gained by converting to solar energy panels. It will estimate the cost of conversion— with the federal, state and city incentives factored in — and you will be linked directly to a number of Bay Area-solar panel installers.

CH2M Hill is not the only company conducting such solar surveys, and others are even going global. Seattle-based 3Tier is steadily mapping the solar, wind and hydro power potential of the entire planet, with its REmapping the World initiative. Utilities and businesses can use the 3Tier website to prospect for the best locations for wind power projects, while ordinary citizens can check the rough solar potential of their home address. What kind of dividends this will pay in an energy hungry, globally warming world is hard to say, but if San Francisco is any indication, they could be big ones.

San Francisco already has about 6.5mW of solar power hardware installed in the city, most of it from a relatively small number of big commercial and municipal projects. The target aimed is for 31mW of solar by 2012, part of a bigger plan to provide 50mW of total renewable energy by the same year. Mayor Newsom's office is also identifying the 1,500 business that have the biggest solar potential in San Francisco — saving them equally big money — and is offering a special incentive to solar contractors who employ graduates of San Francisco's workforce training program, part of the mayor's push for green jobs. "Everyone's talking about green jobs, but to say is not to do,' he says. "We want to actually do this.'

The shift to renewable energy won't happen on its own — it needs smart government policies and smart technological innovations. Solar mapping is a good example of both.Incentives plus innovations go a long way to make solar power a reality.

To most of us, having solar power is still a long time from now. The high investment costs certainly put many people off. The government should lead the away by making compulsory for public buildings to be green and create a demand for photovoltaic cells. At the same time, offer good tax incentives or rebates for installing them. Only when there is a healthy demand can the solar panels be made and sold at affordable prices.