This article echoes a lot of points made when pointing out how renewable energy will not solve our load shedding problem.
Excerpts from the article are presented below, however the article is very detailed and well referenced, so it is highly recommended that it is read in its entirety:
In the early stages of moving toward increasing generation from intermittent renewables – say, to get 10% of the generation from the renewables — a grid operator can start by simply adding some new wind turbines or solar panels to the system, and by then accepting that power onto the grid when it is available. However, there will be substantial times when no such power is available (e.g., calm nights). Therefore, all or nearly all pre-existing fossil fuel capacity must be maintained, even though some of it may be idle much of the time. Although the fuel cost of the renewables is zero, the operator must pay the capital cost of two overlapping and duplicative systems to the extent of the renewable capacity.
However, no amount of excess capacity can make a wind/solar-only system generate any electricity on a completely calm night, nor any meaningful amount on a heavily overcast and calm winter day. If the backup comes from fossil fuel facilities, very nearly the full fleet must still be maintained.
But, since much of the time will be dark and/or calm, still the percentage of electricity coming from the renewables will only be around 30%, and the decrease in carbon emissions from the backup fossil fuel plants will be even less, since they must often be kept on “spinning reserve” to be ready to step in when the wind and sun die.
Germany is the leader in Europe in its power generation per capita from renewables, through its so-called Energiewende, having gotten the percentage of its electricity from wind and solar all the way up to about 30%, and at times somewhat beyond. However, the consequence of that effort has been an approximate tripling of the cost of electricity to consumers, to about 30 cents per kWh. (The average consumer price of electricity to the consumer in the U.S. is approximately 10 cents per kWh.) Analyses of the soaring price of electricity in Germany place the blame squarely on excess costs that have been necessarily incurred to try to get to a stable, functioning, 24/7 system with so much input from intermittent renewables.
First, massive “excess” wind and solar capacity has been installed to try to deal with days of light wind and heavy clouds. And for the completely calm nights and overcast winter days when the wind and solar sources produce nothing or next-to-nothing, nearly the entire fleet of fossil fuel plants has been maintained and ready to go, even though those sources end up being idle much of the time. (Actually, since Germany during this time has been shutting down all of its nuclear power plants, it has been building additional coal plants to back up its renewables.) And then, some means have had to be found to deal with the surges of available electricity when the wind and sun suddenly blow and shine together at full strength at the same time.
Every 10 new units worth of wind power installation has to be backed up with some eight units worth of fossil fuel generation. This is because fossil fuel plants have to power up suddenly to meet the deficiencies of intermittent renewables. In short, renewables do not provide an escape route from fossil fuel use without which they are unsustainable.https://www.manhattancontrarian.com/the-disastrous-economics-of-trying-to-power