Natural gas, best friend of renewables?
You don’t need to know much about wind and solar technologies to realize that they’re not much use when the sun doesn’t shine and the wind doesn’t blow. That’s why power grids need some other source of energy to draw from at nights and on calm days — most often natural gas plants that can be turned on and off quickly, so as to minimize wasted energy.
But it also appears that having those “fastreacting” fossil fuel plants around may have fostered the growth of renewables as well, according to a working paper published Monday by the National Bureau of Economic Research.
Researchers from France, Italy and the U.S. took a historical look at the question, by measuring adoption of wind and solar energy across developed countries between 1990 and 2013. They found that over the long term, natural gas generating capacity was correlated with greater investments in renewables, suggesting that the two are complementary, not in conflict.
Now, it’s important to note what’s not included in the “fast-reacting” category: coal and nuclear plants. Those tend to operate as ei-
ther on or off, making them not very useful as backup power for wind and solar. For that reason, we might not need more fossil fuel capacity overall, study coauthor David Popp of Syracuse University says — just fewer so-called baseload generators that operate all time and more flexible natural gas plants.
And of course, that’s already happening on its own, since the U.S. shale boom has made gas cheap and abundant. The Energy Information Administration already thinks 2016 will be the year in which natural gas consumption surpasses that of coal. Accordingly, some big companies — like Shell — are shifting away from oil in favor of gas and renewables.
The need for that backup capacity will also shrink as scientists come up with better ways to store energy from wind and solar.
It’s unclear whether there is a causal link between natural gas capacity and renewable investment, or if it’s just a correlation, cautions Patrick Luckow of the Cambridge, Mass.based consultancy Synapse Energy Economics.
“The countries with more fast-reacting fossil fuels might have more modern power systems in general, and be more amenable to, accepting or encouraging of renewable fuels as well,” Luckow says. “But it is absolutely true that flexible resources help integrate renewables significantly.”
This balancing act is perhaps most advanced in California, which has set ambitious renewable fuels targets and has added natural gas capacity to help meet them. Luckow says there’s no standard ratio of how much natural gas capacity you need for every kilowatthour of solar or wind, but it’s less than one-to-one, meaning it shouldn’t be too hard to get up to 50 percent renewables.
But backup power isn’t the only variable in advancing renewables. To become a major player in the energy mix, wind, solar and other renewables must navigate obstacles such as financing, regulatory holdups and competition with lowercost sources.