The overall carbon emissions associated with electric cars decrease as the electricity used to recharge them gets cleaner.
And the latest statistics from the International Energy Agency (IEA) will be good news indeed for electric-car drivers.
Last year saw record growth in renewable energy, according to the IEA, which surpassed coal to become the largest source of new installed capacity in the world.
Based on that impressive performance, the agency is raising its five-year renewable-energy growth forecast.
The revised forecast predicts 13 percent greater renewable-energy growth between 2015 and 2021 than last year's forecast.
That optimism is due largely to what the IEA views as stronger backing by policymakers in the U.S., China, India, and Mexico.
Predicted regional electricity growth 2015-2021 (from IEA Medium-Term Renewable Market Report 2016)
Over the same period, costs are expected to drop by 25 percent for solar and 15 percent for onshore wind generation.
Last year, renewable-energy sources represented more than half the new power capacity around the world, according to the IEA.
The 153 gigawatts of renewable-energy generating capacity installed was 15 percent higher than the previous year.
That total included a record 66 GW of wind installations, as well as 49 GW of solar installations, the agency said.
China accounted for about 40 percent of all renewable-energy installations, including about half of the wind installations.
However, a presentation by IEA executive director Fatih Birol (pdf) showed that, in China and other developing economies, renewable energy is just part of overall growth in electricity supply—including added fossil-fuel capacity.
Globally, renewable energy should represent the majority of that growth in the "medium term," the IEA noted.
In contrast, the presentation showed that in the U.S., Europe, and Japan, renewable-energy growth is starting to displace other forms of electricity generation.
Over the next five years, the IEA predicts that renewable energy will remain the fastest growing source of electricity generation.
The agency expects it to expand its share of the global generating mix from 23 percent in 2015 to 28 percent in 2021.
But this will be what the IEA calls "two-speed" growth, with Asian nations continuing to add renewable energy as part of overall increases in generating capacity.
Only the U.S., Europe, and Japan will actually use renewable energy to replace fossil fuels, it says.
Photovoltaic solar power field at Volkswagen plant in Chattanooga, Tennessee
In addition, the IEA is concerned that current policies supporting renewable energy may be reversed in some countries.
Integrating new renewable-energy capacity is also proving to be a challenge in certain countries, the agency noted.
Nonetheless, the IEA believes these obstacles can be overcome—and that the true potential of renewable energy still remains largely untapped.