Cities like Reykjavik and Zurich have already quit using fossil fuels to produce power, and others plan to cut back. A new survey reveals just far 162 of them have gone.

As global climate talks near, Beijing and 10 other Chinese cities recently announced they will peak their heat-trapping emissions (about equal to those of Brazil) before China’s national target of 2030. More than a dozen U.S. cities including New York joined in pledging emission cuts.

How well, though, are other cities doing in quitting fossil fuels? A glimpse emerges from a survey, released Thursday, of the current power mix of 162 cities worldwide. Many are moving to reduce carbon emissions, but some are further along than others.

Share of electric power obtained from nonfossil fuels Data provided by cities NG STAFFSOURCES: CDP; AECOM

Brazil’s cities fared best. They reported getting an average of 76 percent of their electricity from cleaner sources, primarily hydropower, and their European counterparts averaged 59 percent, according to the data compiled by CDP (formerly the Carbon Disclosure Project), a not-for-profit group nudging cities and companies to address climate change.

Overall, North American cities weren’t quite as green, but Asian Pacific ones fared the worst, receiving only 15 percent—on average—of their electricity from cleaner sources such as nuclear, biomass, geothermal, hydro, solar, or wind.

Still, in almost every region, some cities stand out. Hong Kong, now heavily dependent on coal and gas, reports using financial incentives to boost investments in renewable energy. Austin, Texas, aims to get 55 percent of its electricity from renewables by 2025. Stockholm, San Francisco and Vancouver are aiming for 100 percent by mid-century.

“We definitely see cities as being on the leading edge. This is their moment,” says Kyra Appleby, head of CDP’s cities program, noting most are using a variety of technologies to shift from fossil fuels. She says they’re often hubs of innovation and can act more quickly than states or countries.

Plus, many see the need to act. “Climate change isn’t a political issue—it’s a reality for cities, many of which are right now enduring drought, extreme weather, and wildfires as a result,” the mayors of Los Angeles, Philadelphia, and Houston said last month in launching the #ClimateMayors Twitter campaign in advance of the United Nations’ climate summit that begins Nov. 30 in Paris.

The CDP survey, which relies on self-reporting from cities because of a dearth of global data at the city level, reveals vast gaps between those relying on fossil fuels and those nixing them.

No fossil fuels . Twenty-one cities say they use no fossil fuels to produce electricity. They include 16 smaller cities in Brazil that rely entirely or almost entirely on hydropower. The other five cities (aside from Reykjavik and Zurich ) are Canada’s Winnipeg, Ethiopia’s Addis Ababa and Italy’s Padova—each of which relies heavily on hydro.

. Twenty-one cities say they use no fossil fuels to produce electricity. They include 16 smaller cities in Brazil that rely entirely or almost entirely on hydropower. The other five cities (aside from Reykjavik and Zurich ) are Canada’s Winnipeg, Ethiopia’s Addis Ababa and Italy’s Padova—each of which relies heavily on hydro. Very few . Another 15 say less than 10 percent of their power comes from fossil fuels, including Paris, Oslo, Stockholm, Seattle as well as four cities in Brazil and four in Canada. Many also rely heavily on hydropower, but two of them—Toronto and Paris—get at least half their power from nuclear plants.

. Another 15 say less than 10 percent of their power comes from fossil fuels, including Paris, Oslo, Stockholm, Seattle as well as four cities in Brazil and four in Canada. Many also rely heavily on hydropower, but two of them—Toronto and Paris—get at least half their power from nuclear plants. Mostly . Eight say they use fossil fuels to produce at least 90 percent of their power. They include Tokyo, Singapore and Seoul, which rely mostly on gas, Gibraltar (oil) and South Africa’ Cape Town (coal.)

. Eight say they use fossil fuels to produce at least 90 percent of their power. They include Tokyo, Singapore and Seoul, which rely mostly on gas, Gibraltar (oil) and South Africa’ Cape Town (coal.) Only fossil fuels. Another eight say they’re 100-percent reliant on oil, gas or coal to generate electricity. They include Sydney and Pretoria, which use mostly coal, Moscow and Mexico City (gas) and Venezuela’s Caracas (oil.)

The story is part of a special series that explores energy issues. For more, visit The Great Energy Challenge.

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