Solar power grew at a record-breaking pace in 2015 — and it looks on track to do so again in 2016. Large cities have been leading the way on this growth. In fact, they now account for about 6% of the country’s solar, despite only having 0.1% of the land area.

As population centers, major cities continue to play a key role in solar’s growth. And they stand to benefit substantially as a result. Cities are major sources of electricity demand, and with millions of rooftops suitable for solar, they have the potential to be major sources of clean energy as well.

Which cities are leading the charge?

Each year, the Environment America Research & Policy Center releases its Shining Cities report. The report looks at the top 20 cities for solar power throughout the country.

Top 20 cities

Looking down the list, many of these cities should come as no surprise. We expect to see places like Honolulu, Los Angeles, and San Francisco on the list.

Solar’s unexpected hotspots

What about cities like Las Vegas and Indianapolis? It may surprise some people to see them on the list. It turns out that these cities benefit particularly from utility-scale solar. That’s not to say rooftop solar doesn’t have its place in them, but they’ve done better than most cities at attracting large-scale installations.

Indianapolis, for example, has a 17.5 MW system located at its airport, as well as a 9 MW array at the Indianapolis Motor Speedway. And Las Vegas is pursuing a goal of completely powering itself with renewable energy — much of that being solar.

City rooftops

While utility-scale solar can boost a city’s solar ranking, city rooftops can support a surprisingly large amount of solar. As a recent Department of Energy study found, we could get 40% of all the electricity we need in the U.S. just from rooftop solar.

That’s true for any city in the U.S. But people in any of the top 20 cities are in an even better position to be part of the solar trend. That’s especially true in states with strong solar policies, like California and New York.

Incentives and policies still key for solar

Whether it’s at the state or local level, incentives like rebates and net metering are still important for the continued success of solar. Looking through the list, 6 of the top 20 cities are located in California. California also has the number 1 and 2 spots in Los Angeles and San Diego. This isn’t just a coincidence. California has been a leader in strong policies for clean energy.

Hawaii is another state with fairly good solar incentives, which is part of the reason why Honolulu has the most solar installed per capita. With the highest electricity prices in the nation, solar is even more attractive there. The need to ship fuels to the island means a technology like solar offers substantial savings to residents and businesses alike.

Cities have only begun to tap their solar potential. Cities like Los Angeles, New York, and Austin have the potential to add tens to hundreds of times more solar energy than they currently have. Continued support for strong solar policies at all government levels will be key for solar’s continued growth in these cities and throughout the country.