The current build-out of solar and wind worldwide is enabled by a parallel buildout of natural gas fired power plants. This from a recent article in The Washington Post:
“We’re at a time of deeply ambitious plans for clean energy growth…
“Only, there’s a problem: Because of the particular nature of clean energy sources like solar and wind, you can’t simply add them to the grid in large volumes and think that’s the end of the story. Rather, because these sources of electricity generation are “intermittent” — solar fluctuates with weather and the daily cycle, wind fluctuates with the wind — there has to be some means of continuing to provide electricity even when they go dark. And the more renewables you have, the bigger this problem can be.
“Now, a new study suggests that at least so far, solving that problem has ironically involved more fossil fuels — and more particularly, installing a large number of fast-ramping natural gas plants, which can fill in quickly whenever renewable generation slips.”
The abstract of the study (all that’s available free), which was published as a working paper by the National Bureau for economic research, says: “All other things equal, a 1% percent increase in the share of fast reacting fossil technologies is associated with a 0.88% percent increase in renewable generation capacity in the long term.”
Nuclear and coal plants are very slow to start and stop; they provide baseline power but can’t be used to top off the grid. Oil plants are possible as peakers but can’t spool up as fast as gas turbines and are both dirty and expensive to run even at the current cost of oil. Hydro can be turned on and off if there is the right amount of water behind the dam; but hydro is not available everywhere. Hauling electricity long distances (for example from where the wind is blowing to where it’s not) involves transmission loss and requires grid infrastructure which may or may not be where it needs to be. Large scale battery technology is still in the grant-sucking phase and involves huge amount of toxic waste from used batteries. That leaves natural gas to take up the slack. It’s the “fast reacting fossil fuel” the study is talking about.
The abstract of the study doesn’t mention it but the fact that small natural gas generating plants can be built economically means that these plants can be located near the renewable sources so that new grid capacity doesn’t have to be built to get the backup power to where it’s needed. Moreover, a distributed grid with power usually generated and consumed in the same locations is much more resistant to either natural catastrophes or sabotage including hacker attacks (subject for a future post).
So the economics of renewables depends heavily on the price and availability of natural gas. See Natural Gas vs. Climate Change for steps I think we should be taking now to assure we have natural gas when and where we need it at a good price as well as for the objections to use of natural gas and my conflict of interest in recommending it.
If you believe that we are on the cusp of a climate meltdown, you should support abundant natural gas both because it emits 50% less CO2 per kilowatt of electricity generated than coal AND because it is an essential part of reliable electricity in a grid which also uses renewable sources. Even if you are just interested in cheap and reliable electricity, the combination of well-sited renewables and cheap, clean natural gas makes sense.
Other posts in the climate change series:
Combating Climate Change (the nuclear option)