Project Sunroof's red dots display neighborhood view on solar installations

Launched in 2015, a Google project has been holding the hands of people interested in going solar in their homes with the how-to and as important the why-to if to save on costs.

It is a walk-through called Project Sunroof, a find-out tool for people thinking about .

Project Sunroof has walked people through all the information-gathering steps of installing solar panels: How do you tell if your house gets enough sun to make this a good idea? How many panels do you need? How much money do you save? Who can install them?

"After you tell it where you live, its algorithms estimate how much solar energy falls on your roof, calculate how much solar panels would reduce your electricity bill, and deliver estimates from local installation firms like Solar City," said The Atlantic.

The project web site said you can "Compare loan, lease, and purchase options for your solar panels based on your results. You can also "See a list of local solar installers."

Project Sunroof is again in the news.

Roger Cheng in CNET reported on what's new on Monday. "Google on Monday showed off a new update to its Project Sunroof initiative that lets you look at the existing solar installations in the US. More importantly, Project Sunroof Data Explorer can show you if your neighbors have already upgraded to solar."

Robinson Meyer, an associate editor at The Atlantic, talked about the showing of houses with solar. Project Sunroof In its map view puts red dots over houses that appear to have solar panels on the roof, and this brought Meyer into observations about keeping-up-with-the-solar-joneses.

"One of the best predictors of whether people install solar panels on their house isn't their age, their race, their level of income, or their political affiliation. It's whether their neighbors did it first."

He said, "Project Sunroof will now not only inform users how much sun hits their roof, or how much solar panels would save them per month, but also which of their neighbors have taken the plunge first."

He mentioned Kenneth Gillingham, a professor of economics at Yale University, who did a study that helped to establish the finding.

But wait. Is there a privacy issue? Carl Elkin, an engineer at Google who launched the project in 2015, made several points in the article.

He said that this is already satellite imagery. He also said that Google only stores its installation data at the latitude-longitude level.

"We're not looking at individuals, we're looking at buildings," he told Meyer. "And we're not publishing a list of these buildings."

Project Sunroof provides data for homes across the United States, assessed with its algorithms. "Now—in a nod to the powerful peer effects of solar power—it will also show you which of your neighbors have already installed panels," Meyer said.

Cheng: "Google said it combined machine learning with Google Maps and Google Earth imagery to determine which houses have ."

Explore further: Google can tell you if solar roof panels will pay off

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