How Much Do Solar and Wind Require Natural Gas Backup?
Windmills in a row on cloudy weather, wide shot, denmark
As I’m mentioned, I’m a part of a pro-nuke online community that has a strange antipathy toward renewables. One might think that proponents of one low-carbon energy solution would respect those of another, but not in this case. They offer a variety of reasons that I find interesting, but every one of them seems spurious at least to some degree.
One of maybe a dozen is that, because solar and wind are intermittent, they require the construction of natural gas plants for back-up. To be fair, there is some truth to this, at least the way wind has been implemented in the U.S. to this point, representing, as it does, about 5% of the total grid-mix. Of course, there are other forms of backup, i.e., hydro, there are energy storage technologies coming online, and, as more wind is built across huge expanses, less point-backup is required since wind velocities tend to balance out across larger geographies.
Here’s an article in GreenTechMedia that provides a few case studies, showing specifically why gas backup is not as strict a requirement as naysayers claim.
Craig,
The article doesn’t refute the (true) challenge of balance power. It measures overall gas demand compared with prior years when less renewable power had penetrated the grid. But while gas (or hydro) is needed to balance wind and solar when the wind or solar generation falters, the gas demand is specifically reduced when the wind and solar generation are producing strongly… On average, you should have a reduction in gas demand overall, as the renewables offset some of the gas generation.
The only way that gas could remain constant would be if baseload generation were tamped back – dispatch switching from coal to gas… showing that indeed the grid itself had to accommodate the increased penetration of renewables by utilizing gas balance power.
That’s not a bad thing (switching from coal to natural gas is a bigger step forward for the environment than switching from natural gas to full renewables), but the Greentech Media article is disingenuous by attempting to claim that constant gas utilization disproves the claim of the need for balance power.
In many cases, the needed balance power can easily come from uprating hydroelectric dams, so that the volume flowing through the turbines can be varied to whatever extent that the natural geology and ecosystem can handle… but still there will be a need for spinning reserves and balance power.
It’s a curious criticism from a nuclear group, since there is no load-following nuclear reactor in America, and there is not likely to be one within the next two decades. So nuclear power requires balance power and pumped hydrostorage as well.
There are energy storage technologies coming online, and, as more wind is built across huge expanses, less point-backup is required since wind velocities tend to balance out across larger geographies.
One of maybe a dozen is that, because solar and wind are intermittent, they require the construction of natural gas plants for back-up.