Solar power may currently make up less than 2% of the world’s energy mix, but the outlook of solar company executives is, uh, sunny.

“What’s important is new [energy] generation, and in the US, renewables are 70% of new generation. It’s game over,” said Tom Werner, CEO of SunPower, the California-based solar company, speaking at the Fortune Global Sustainability Forum on Thursday in Yunnan, China. “That’s why big companies in electric distribution, oil and gas are flooding into renewables.”

Christian Rynning-Tønnesen, CEO of Statkraft, the Norwegian renewable producer, was similarly bullish. “Solar will be the biggest source for electricity on the planet from 2035,” he said, adding that his calculations show renewables accounting for 80% of electricity production by 2050.

“The conversion to renewables is inevitable and it’s happening—it’s climate change and it’s costs…capitalism works,” said Werner, who claims solar will continue to benefit from the equivalent of technology’s Moore’s Law (the price of the technology has been plummeting).

What about the argument that you can’t power things when the sun isn’t out and the wind isn’t blowing?  Werner conceded storage is a challenge—particularly going from summer to winter—but argues that’s a tired argument. He points to ongoing innovation around storage and energy distribution, and says a flexible grid will be a large part of the solution.

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