Axios' Amy Harder explores why, despite rapid renewables growth and falling costs, future grids powered by these resources alone would face daunting hurdles.
Driving the news: A 100% renewable electricity system would greatly increase the risk of blackouts, per internal modeling by the consultancy Wood Mackenzie.
- Renewable energy would also need significant government support to remain afloat, the work described to Axios in an interview shows.
- It's part of the analysis conducted for a study released in June which found that such a transition would cost $4.5 trillion within a couple decades.
What they’re saying: “Not only are [renewables] causing intermittency issues, they can no longer recover costs in the power market,” said Robert Whaley, a senior WoodMac analyst.
- "At the point of 100% saturation, they’re completely dependent upon government policy or subsidy," he said.
- Whaley said a lot of markets could eventually handle 45%–50% wind and solar. "It’s when you get past that 50% mark that it gets trickier and more nuanced."
But, but, but: The analysis doesn't assume technological breakthroughs, which could lower costs and improve storage capabilities that minimize blackout risks.
By the numbers: Right now America’s electricity mix is mostly gas and coal (63%) and about 17% renewable sources. This includes 6.5% wind, 2.3% solar and 7% hydropower.
Where it stands: The chart above illustrates steep declines in wind and solar costs compared to natural gas and coal. The visualized renewable costs exclude federal tax credits (they’re even cheaper with them).
Why you'll hear about this again: There's an ongoing fight between advocates who argue a 100% renewable grid would be affordable and stable, and those who say other resources — including nuclear and gas with CO2 capture — should be on the table.