You are here

Solar and the City: Online Map to Show NYC's Solar Potential

October 13, 2010 - 11:32am



Think Google Maps for solar.

Type in an address and instead of directions to a restaurant or movie theater, a home’s solar potential comes up—and not just that, but energy and cost savings too.

San Francisco and Boston have solar maps, and soon New York City will publish its own extensive online tool.

That means starting early next year people will be able to determine how much solar power can be obtained from the rooftops of their homes or businesses in just a few clicks.

“This is about streamlining the process,” says Tria Case, university director of sustainability for the City University of New York (CUNY), which partnered with the city to create the maps.

“Some people hear solar and think it’s complicated and expensive. But once they see the step-by-step actions they can take and calculate its true value, it will be easier to see the real worth of solar on their roof,” says Case.

Imitate success

Click on San Francisco’s map, and you’ll see hundreds of little, yellow, red and purple dots marking rooftop solar panels splashed across the aerial-view map, similar to a Google Earth platform. 

These maps not only offer up solar information, but also populate themselves with symbols when users—home owners, businesses and schools—enter in their solar panel installation projects.

When the tool launched in summer 2007, San Francisco had 554 solar installations marked on the map. Today, that number is 2,073, with a total capacity of 11 MW. 

“The solar map has absolutely played a big part in supporting interested building owners and increasing solar installations,” says Danielle Murray, renewable energy program manager for the San Francisco Department of the Environment.  She cites their municipal incentive and outreach program, GoSolarSF, as another key factor in the four-fold increase in solar installations San Francisco has experienced since mid 2007.

“We wanted to make it easier for people to understand the technologies, costs and available incentives by providing this one-stop resource, and show them that they are not alone—no matter where you live in the city, you'll find a neighbor with solar,” she adds.

Officials in New York, which experts say has enough solar energy to power the city twice over, are hoping to mimic San Francisco’s success.

Designated a Solar America City by the U.S. Department of Energy in 2007, the Big Apple had an initial goal of 8.1 MW of photovoltaics installed by 2015.

"Now that we have addressed key barriers, and continue to do so,” Case says, “they are projecting that NYC will have 45 to 70 MW installed by 2015.”

With a $200,000 award from Recovery Act funds administered through the Solar America Cities program, CUNY was tasked with generating a solar map for the entire city. The total project cost was about $640,000.

How did they do that?

They say New York never sleeps, and that expression couldn’t have been truer last spring.

To get all this data, a twin-engine Shrike Commander flew serial missions during the nights over a couple weeks in May, zapping lasers to collect highly precise images of the city, including wetlands, trees and rooftops, with an emphasis on sun and shade.

Each flight took about nine hours, and the images were captured by a team from Sanborn Map Company, using a technology known as LIDAR, or Light Detection and Ranging.

The maps, which will also be used to generate up-to-date flooding maps, are being developed by the Center for Advanced Research of Spatial Information (CARSI) at CUNY’s Hunter College.

The New York City solar map will also contain unique tools that city planners and Con Edison, the utility company, can utilize to plan where best to integrate solar, like planning for new substations for the ever-growing city.

“A transition to clean energy sources requires a cohesive, strategic plan—and not just a plan, but the tools to implement it.” Case says.  “The NYC solar map will be a tremendous tool for selling, planning and installing solar in NYC.”