Electricity demand must always have the right amount of supply, not too much or not too little. Too much or too little will cause blackouts. Blackouts are when they shut off your electricity.
Without enough power the lights go out – blackouts!
The first thing you must know about electric grids is that they store no power themselves. What this means is that as users take electricity off of a grid there has to be electricity generated to put on the grid. If this doesn’t happen, the electric grid will have blackouts. Sometimes small, sometimes large.
When grid operators know that there are going to be shortages, they plan rolling blackouts. I lived in California in the 70s when there were energy shortages. They would shut down entire cities for two to four hours at a time and then move on to other cities.
In the most basic sense, there are three types of electricity generation. Base power which is nuclear and coal. Dispatchable or on-demand power, which is usually natural gas, and a small amount is oil. Then there is part-time, unreliable, weather dependent renewables a.k.a. wind and solar. Industrial scale batteries are emerging, but they are expensive, and we have ridiculously small amount of battery storage.
Hydroelectric power gets an honorable mention and doesn’t fit well in any of the categories. Because they can run pretty steady as long as the water is available like in the Pacific Northwest for instance. Yet in times of drought, like in California now, they can produce little or no electricity. When hydro is available it is like a base power.
Base power tends to run all the time at a steady rate. It is not easily turned up and down to meet the demand of the electric grid or the variability of wind and solar. On demand power can be turned up and down on short notice to provide grid stability and meet the variable demand. The unreliables only work when the wind blows or the sun shines. The unreliables produce little or no energy 70%1 of the time.
Different amounts of electricity are used all the time at different times. Peak demand is when the most is used and it’s usually between 5:00 and 9:00 o’clock in the evening. And the greatest peak demand is when it’s very hot or very cold because people want to heat or air condition their homes.
California, Texas, and Germany have all been adding a lot of wind and solar to their electric grids. At the same time, they have been closing coal and nuclear power plants. They have not been adding enough part-time power, to even equal the full-time power they have taken offline.
2/3 of the United states are expecting electricity shortages and blackouts this summer and beyond. Because too much full-time power has been taken offline, mostly coal. Full time power is called firm power because it can be relied upon. In order to keep our electric grid, stable we should have about 115% of peak demand in firm power. Because at any time some of the power plants can be interrupted or need to be shut down.
One of the reasons our grids have become unstable is that there is a reliance on undependable weather dependent power. If we don’t have enough firm power when the wind isn’t blowing or the sun isn’t shining much, blackouts will happen.
This is where 2/3 of our country finds itself today. These policies are turning us into a third world country with unreliable undependable electric grids.
The vast majority of Americans enjoy affordable full-time electricity and want to keep it. We have been told a lot of misinformation about our electric grids and wind and solar. We will cover more of this in other posts.
- The capacity factor in this source our generous for wind and solar. I have done the math for onshore and offshore wind in many places. I’m sure wind in the United states typically has a capacity factor of 25 to 32%. Offshore wind in Europe has an average of 42%, but there have been years and months where there are wind droughts, and they produce 20 to 50% less electricity.
Wind also has an issue in that it is common weather pattern for the wind to blow very little or not at all when it is hottest or coldest. In most areas of the country, even in areas good for wind, there can be a day or a week with very little wind. It is highly variable. Incidentally a Harvard study points out that if we built the few 100,000 wind towers we need for more electricity it would warm the United states by nearly a half a degree.
There isn’t a lot of data for solar plants. But what I have seen is that they vary from 15% in the northern parts of our country to 20 to 25% in the very sunny parts of our country. Solar panels also wear out overtime and when they get dirty, or it is cloudy they produce less energy. Solar panels also heat the air above them 25 to 36°. That is significant on the large scale.