Source of this article: AAAS
9/21/2015 — Much of the nation's energy policy is based on the idea that clean renewable energy sources like wind and solar require huge quantities of storage before they can make a dent in the greenhouse gas emissions from the generation of electricity. A new Harvard study contradicts that conventional wisdom. The analysis published today in the journal Energy & Environmental Science says the supply of wind and solar power could be increased tenfold with no additional storage.
"There's no question that it would be better to have more and better storage and a sensible long-term strategy for the grid will have much more storage than today," said coauthor David Keith, Gordon McKay, a physics professor at Harvard. "But you don't have to wait for that before deploying more variable renewables."
The study conducted by Keith and graduate student Hossein Safaei asked: In order to drastically reduce planet-warming carbon emissions from electricity generation, what amount of electricity storage is economically efficient?
Since the wind doesn't always blow, nor the sun always shine, many assume that lots of storage capacity is needed if wind turbines and solar farms are to contribute a significant share of the nation's energy demands.
But storage "is not the only strategy to achieve a low-carbon electricity grid," according to Safaei.
The finding that renewable energy can be dramatically increased without widespread deployment of batteries is "good news," says Sally M. Benson, a professor of energy resources engineering at Stanford University, because "more time and R&D is needed to decrease the cost of [bulk electricity story] and to scale-up production." Benson was not involved in the Harvard research project.
Another independent observer, Jay Apt, a professor of engineering at Carnegie Mellon University, added that the Harvard study makes clear that "the cost of removing pollution from electric generation is lowest when an all-of-the-above strategy is used."
Keith and Safaei hope their analysis will inform both R&D investment decisions and government policy directions.
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The study was funded by Bill Gates through the Fund for Innovative Climate and Energy Research.