Solar neighborhoods

Neighbors that go solar together, stay together.

Research proves the spread of solar is a deeply social affair.

Word-of-mouth is key to the spread of disruptive technologies. People often seek out the trusted opinion of a friend or family member before they are willing to try something outside of the status quo.

Solar technology spreads in a similar way, with one striking difference: neighbors can be so influential to a person’s decision to go solar that one solar home has the power to set off a chain reaction in their community.

‘The Neighbor Effect’ fuels solar’s exponential growth

Just how big is the neighbor effect when all the circumstances are right? The 2014 paper “Spatial Patterns of Solar Photovoltaic System Adoption” looked at the neighbor effect for an average Connecticut town with roughly 21,000 people. If two households within half a mile of each other go solar less than six months apart, this will set off a chain reaction in the neighborhood. A year later, 26 households in close proximity of each other will have done the same.

solar San Jose

Interactive chart showing the contagious spread of solar in San Jose, California. Source: The Economist.

Increasing the distance between solar installations decreases the contagion effect, but doesn’t make it disappear. When installations take place 1 to 4 miles from each other, it will still trigger 7 more new installations within a year.

And the neighbor effect not only wields its influence on individual households but also on neighboring towns. Towns with a high adoption of solar actually inspire nearby towns to investigate how they can encourage solar power at a local level as well. The paper’s authors described the resulting pattern as a “wave-like centrifugal” growth, providing visual proof that solar is indeed a deeply social affair.

The solar revolution originates in small towns, not big cities

The study also discovered that small towns are the quiet heroes of the solar revolution.

Typically, we expect the first people to adopt new technologies to live in big cities where population density is high. With solar technology, on the other hand, it’s people living in small towns that lead the way.

Why does solar break with the regular way new technologies spread? Analyzing patterns and clusters of new solar installations in Connecticut, the research suggests that the apartment buildings dotting Connecticut’s larger cities are the culprit. Although roofs on most of these buildings are perfectly suitable for a solar system, plans get typically tripped up by red tape and split incentives: the uneven distribution of costs and benefits between landlords and tenants. Dominated by owner-occupied, single-family homes, most smaller towns avoid these pitfalls.

Another factor might be that, despite high density, the social fabric in bigger cities is more loosely knit than in smaller towns. If your neighbors pop in for coffee now and then, more gets discussed than when you keep struggling to remember the names of the people in your building.  

But even though solar is having a harder time in bigger cities, this doesn’t mean density isn’t important. To influence each other or to just see that intriguing new installation on your neighbor’s roof, people still need to live close enough together.

Solar isn’t just for rich people, either

Finally, the paper tears down one more popular misconception about solar.

The researchers discovered the adaptation of solar in the wealthiest parts of Connecticut was actually lower than average. Solar turned out to be most popular in the middle income range, suggesting that wealthy neighborhoods may not find the prospect of locking in predictable solar electricity costs for years to be as compelling.

Or, maybe they just live too darn far away from their neighbors.

States and towns can use incentives to accelerate solar growth

Of course, advice from neighbors or friends is not the only thing that convinces people to hop on the solar train. Financial incentives also play an important role. The state of Connecticut smartly blends both factors. It not only subsidizes the purchase of a solar system, it also tries to fuel the neighbor effect.

Connecticut’s Solarize program, which started in 2012, mostly targets medium and smaller towns. First, it helps them choose a preferred installer and negotiate a group discount that gets better once more people sign up. Then, the program kicks off an intense grassroots campaign with information sessions, local advertising and local ambassadors. The researchers see Solarize’s community approach as a key factor in the rapid spread of solar in Connecticut.

Sungevity’s referral program builds on the ‘Neighbor Effect’

Does all of this sound eerily familiar? That’s because Sungevity has been working in very similar ways for years to tap into the ‘Neighbor Effect.’ Our online referral center gives our customers the power to instantly reach out to their friends and family and share their enthusiasm for solar. Our local ambassadors tirelessly educate and excite people about solar at events and local Lowe’s stores.

We also see the power of these social interactions every day: the friend-to-friend advice that inspires a domino effect; how one glittering solar system on a street can kickstart hundreds of neighborhood conversations.

Ready to start the conversation on your block? Click here to see if solar could work for you.

Posted by Leslye Penticoff

Leslye is the Content and Community Manager for Sungevity. She's also an avid coffee drinker and rock climber, and serves on the Board of Directors at Margination, a nonprofit in Troy, NY.