One main issue of renevables (meaning wind- and solarenergy production) is that the amount of available sun or wind is constantly changing. At night there is no sun at all so solar pannels are producing 0 energy. And even during the day it depends on the weather how much sun is shining on the pannels. With windenergy it's the same problem. The amount of wind blowing is varying.
Sometimes they have to shut down windwheels because there is a lot of wind and a lot of sun and that would be too much energy at once for the grid. And then again there are times when it is raining or cloudy and not a lot or no wind and the electricity providers rely on fossil fueled electricity to provide people with enough electricity. But I wouldn't have created this website if there wouldn't be a solution for that problem too. The simple answer is: Energy storage.
There are different ways of energy storage. So that energy providers won't have to shut down windgenerators but can store them instead to release the generated energy into the grit
One possibility is batteries. Especially old batteries from electric cars can be re- used for electricity storages because when used for energy storage the requirements are lower than for cars. I am not sure if Tesla is using new or aleady used batteries but they are onbe of the companies who offer this kind of big scale energy storage. Same as GM and probably some more companies.
A simple but petentially revolutionary way of energy storage is gravity based energy storage. When we climb up a hill by bike, we are accumulating (storing) energy. We release that same energy when we drive the hill back down. This same principle is using Energy Vault.
The idea is that a crane will use excess electricity during times of a lot of wind and sun and / or low energy demand (e.g. at night) and lift blocks of weight and store them a couple or many metres higher above ground. Like a charged battery, those weights (stones or containers of sand) will (like a cyclist driving downhill) release that energy again when the grid is asking for more energy than currently being produced. The same electric motor that was before lifting the stone with the surplus-electricity will now generate electricity and release it into the grid. The main advantage compared to batteries is that it is likely better for the environment because there are no chemicals involved and no mining needed. And inventor Robert Piconi is claiming that his technology therefore will also be cheaper. A small test storage plant was already built in Switzerland (image). A big scale plant will get connected to the grid by a wind power facility near Shanghai in the third quarter of 2023.
By "small scale" I mean batteries for homes who can save the electricity that your solar system on the roof of your house has been generating during the day or during sunny days so that energy can be used during the night or during less sunny days. We don't need (the same amount of) electricity all the time. Often we are not even at home. That's why the green electricity that your roof is producing has to either be connected and sold to the grid or be saved with your own battery at home. A battery like for example Tesla's Power Wall.
I remember my chemistry class, when the teacher showed us how easy we can turn normal water (H2O) into Hydrogen (2H2) and Oxygen (O2) just by using electricity. Please check this video to see a similar experiment to the one we did at school. The electrolysis could be a genius way to store excess renevable electricity from wind and sun. Because right now a lot of potential energy from renewables is being wasted due to lack of energy storage. Excess electricity could be stored in the form of hydrogen near wind and soar farms. Hydrogen can be burned similar to fossil fuel but doesn?t emit any CO2. Instead it turns the H2 (hydrogen) back into H2O (water). One difficulty of hydrogen though is that - unlike gasoline, which is liquid - it has to get compressed to be stored or for example used in cars or airplanes. But there are prototype cars who run on hydrogen already. And Airbus is about to produce a plane powered by hydrogen. So in the future we could for example turn excess electricity into hydrogen and use that hydrogen for airplanes and cars. Hydrogen can (and is already being used) to heat houses (just like CO2 emiting natural gas). H2 could also be turned back into electricity in power plants (like natural gas).
The main issue with hydrogen is that it is very complicated to store it. It is a very light gas (which is why it was used for zeppelins). To store it and increase its density to a reasonable degree it has to get compressed or cooled down. Whgich makes it very unpractical for us in cars for example. Scientists at the Fraunhofer Institute in Germany therefore have invented a way to turn the H2 into a paste by using magnesium. The hydrogen molecules adhere to the magnesium molecules. Creating a paste that can be stored at normal temperatures. To release the H2 molecules of that paste we only need water. Like this a car would only have to carry a tank of water and some hydrogen "powerpaste". The genius thing is that in this chemical reaction it is not only the bonded H2 molecules that are being released. The magnesium leads also to the release of H2 molecules from the water. Like this the energy density is 10 times as high as the one from lithium batteries. It might therefore also be suitable for drones and airplanes. Lithium batteries are currently too heavy (low energy density) for long distance airplane flights. In addition, the paste is not flammable. They are currently also focussing on how to optimize and scale up green hydrogen production.
In many cases we don't need power in the form of electricity but in the form all kinds of energy ultimately end up - heat. For example to heat our homes in winter. Or for steel and concrete production. That's why most of the energy needed in the industry is not necessarily electricity (that of course can always be turned into heat as well) but the actual product needed in the end is simple heat. Whicvh is why
Tommi Eronen and Markku Ylönen who both studied at the same university in Finland came to the idea to store excess energy (instead of being wasted due to lack of storage possibilities) in sand or sandlike material. They so created the sand battery. Excess electricity during times of overproduction (e.g. a lot of windpower and solarpower due to ideal weather conditions) will heat up those tanks of sand which will stay hot for a long period by itself. There are pipes in the sand tank so to use the heat they just blow air into those pipes at one end and on the other end very hot air will come out. That hot air can - if required - be used to create hot water or steam. Technically, it is possible to for example pass that steam through a power generator to turn the heat back into electricity. The company says they are working on a possibility for electricity generation as well.