Tom Scott has done a very good job explaining one of the fundamental problems of renewable energy in relation to the electricity grid and what is being done to try to fix it.
The current situation basically is that as the world is turning its energy sources from the old turbines (fuel, nuclear power, coal, gas, etc.) to renewable (wind, solar, hydro) is more difficult to maintain the balance in the grid.
The solutions are three:
- The first is to storage energy in giant batteries for use in plants where necessary; but this is practically unfeasible on a large scale. To put it in context: the larger battery of this type is in China, occupies the same space as a football field and stores 36 MW: enough to power 12,000 homes only for just one hour.
- The second is to generate energy by a traditional hydraulic system using excess energy at certain times of the day to pump water into a higher deposits, lakes or reservoirs. This is already being done (in Spain by example on the island of El Hierro).
- The third option is more interesting: save energy in distributed batteries at homes, especially in electric cars, electronic devices of all kinds and (soon) in medium sized batteries that can be placed in any corner. In these networked systems various devices (car or photovoltaic panels that people have in their homes) can “sell” in real time their surplus of energy to the grid. Although nevertheless would still be needed some conventional power plants.