Clean Power

Published on May 25th, 2016 | by Joshua S Hill


Google’s Project Sunroof Expands To 42 US States

May 25th, 2016 by  

In an innocuous announcement last month, Google has expanded Project Sunroof to 42 states across the US, up from 10 states in December.

We first heard of Google’s Project Sunroof nearly a year ago. At the time, it was simply the latest in a number of Google’s 20% projects. In the company’s 2004 IPO letter, Google founders Larry Page and Sergey Brin explained the idea: “We encourage our employees, in addition to their regular projects, to spend 20% of their time working on what they think will most benefit Google,” they wrote. “This empowers them to be more creative and innovative. Many of our significant advances have happened in this manner.”

In August of 2015, Carl Elkin wrote about his 20% project, Project Sunroof, an online tool which helps “homeowners explore whether they should go solar or not” by providing access to high-resolution aerial mapping to help calculate a roof’s solar energy potential “without having to climb up any ladders.” We soon discovered that Project Sunroof had teamed up with big names such as SunPower, SunEdison, Sungevity, and more.

Project Sunroof-1

At the time of conception, Project Sunroof was limited to the San Francisco Bay Area, Fresno (in central California), and the Boston area. A few months later it had expanded to include Napa, Sacramento, and Long Island.

In a catch-all post explaining “How technology can help us become more sustainable” on the Google Official Blog, published back in April, Google announced that Sunroof had now expanded to 42 states across the US, making free solar information available to 43 million rooftops and those living beneath them.

Speaking to Greentech Media last week, Nicole Lombardo, head of business development and partnerships at Project Sunroof, explained part of the rationale behind Google’s plans for Project Sunroof:

“Google is in the business of providing universal access to information. So being able to take the imagery that we have and find new use cases for it that can help, in this case catalyze the renewable energy transition here in the U.S. …is within our core.” 

Google is aiming to reach all 50 US states in the coming months, with only Texas, Hawaii, Rhode Island, Idaho, South Dakota, Mississippi, Tennessee, Alaska, and the District of Columbia unable to participate as of writing.

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  • ADW

    Looking at my location they are 2 houses away away from me. Looks like they are using images from 2 years ago so it will not be a good reading for me as I just had three trees come down (rotted) that were shading my southern roof line. I expect it will not see I have solar hot water already in place.

    The tool did get my in-laws house 1.5 miles away and made pretty good estimate on the size of the roof.

    Its not perfect, but it gets people to think about it and that is needed right now.

  • jamesjm

    Make that nine states. Looks like New Jersey is also not a state it currently covers.

  • Matt

    “Your roof may not be ideal for solar panels. Contact a solar provider to learn more.”
    95% of my roof is due east or due west so what I expected.
    Now two overlays would be neat, but harder.
    1) A zoning/policy rating. Are in in a good area to install or one where install don’t even want to try.
    2) HOA restrictions. Even harder to get. But if like mine you can do any PV. And changing a HOA by-laws is harder than cutting your own arm off.

    • Frank

      Mine says the same thing, but I want them, and I am going to try to do it myself. One thing I considered, is maybe adding ground mounted pannels later.

      • GCO

        And funnily enough, the same tool pretends I have many times more the available area and sunlight I actually get (I had solar installed years ago) and, surprise, surprise, also suggests I click on the linked installers/advertisers.

        Project Sunroof may be cute eye-candy, but the numbers it provides are close to purely random, certainly not something to base a multi-thousands$ decision on.
        In my opinion, it’s only about selling leads.

        Want a free assessment with at least some connection to reality? Simply call a local installer directly, one who’ll come on site.

        • Freddy D

          Hopefully it will motivate both owners and vendors to prioritize and schedule the on site visits.

    • Freddy D

      East west use turning out to be better than we thought a few years back because late afternoon power is worth more than noon power.

    • AaronD12

      My HOA by-laws say “no solar”, but the Texas state laws say they must allow solar. (Yes, Texas!) I understand the HOA’s concern — they want the homes to look pretty and consistent, so I’m not going to change their by-laws until the rest of the homes in my area are built out. Then, game on!

    • ddobs

      In 2010 I moved into my home in GA, which is governed by an HOA. The architectural guidelines said “Solar panels: submit for approval.” After submitting very detailed plans for a 16-panel rooftop PV system, and showing the plans to surrounding neighbors, most of them said things like “I don’t think it would be a good idea. It could affect my property value.” Those tepid comments were all it took for the HOA to reject my plans. I submitted two more plans, each one downsizing the systems, but they were all rejected. The last plan had low visibility and the proposed system would be partially seen by the two neighbors directly across from me. The rejection letters were very heavy handed, as if I wanted to build a pig pen in my yard. The HOA has since changed the architectural guidelines to state that solar panel design plans will be rejected if occupants in neighboring homes would be able to see them!, thus effectively banning solar PV systems for all but three homes in the 140 home development. My story was later picked up by the Associated Press and was seen in major English speaking countries around the world. You can read the full story if you do a web search: “Georgia HOA denies couple their solar dream.” I have given up my plan to install a solar power system on my home, but have since become an advocate for Solar Rights legislation in Georgia.

      • Calamity_Jean

        How infuriating.

  • neroden

    Google only covers select cities within these states, so this isn’t really as big a deal as it appears. When they start covering an entire state, that’ll be news.

    It’s theoretically present in my zip code, but it’s doing quite terribly in my neighborhood. I put in my address and it has one of my neighbor’s roofs. And none of my other neighbors, and not mine — drag the target and it refuses to do so because it hasn’t done an estimate for any of the houses in several blocks except that one.

  • Harry Johnson

    This is a great way for people to be introduced to the possibility of rooftop PV.
    Why are 8 states and DC “unable to participate” in this project? Sunny Hawaii and huge Texas should be near the top for solar.

  • RobertM

    Figures Tennessee is one of 8 states not yet in the project.

    • Freddy D

      Hopefully coming soon. Should have pretty reasonable sunshine there and pretty healthy summer AC bills waiting to be reduced.

    • Bob_Wallace

      What’s happened to our Volunteer state? Has it become the We’ll Come Along Later state?

      • RobertM

        What’s happened to our Volunteer state? Has it become the We’ll Come Along Later state? — Bob_Wallace

        Tennessee doesn’t have any state programs for Solar so it makes sense that we have very few installers and will be less likely included in something like this.

  • Freddy D

    Interesting that Google doesn’t account for the higher value of power in the late afternoon vs at noon. As more solar comes on and Time of use pricing becomes more prevalent, mid-day power will sell for less and less. To optimize dollars, west will be the new south when siting solar.

    • GCO

      No idea what this tool actually accounts for, none of its assumptions (e.g. utility rates) are explained — probably because it’d make its shortcomings more glaringly obvious.
      It gets all roofs in my neighborhood completely wrong; misses skylights, edges, shading, existing solar, sees “bumps” where none exist (and still suggests putting PV on top anyway), considers balconies part of the roof, completely fails to account for mandatory setbacks for the fire dpt, and so on.

      The website may be nice, but its conclusions, for all the roofs I looked up, are wildly off, sometimes by an order of magnitude.

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