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Chile Has So Much Solar Energy It's Giving It Away for Free (bloomberg.com)
An anonymous reader shares a Bloomberg report: Chile's solar industry has expanded so quickly that it's giving electricity away for free. Spot prices reached zero in parts of the country on 113 days through April, a number that's on track to beat last year's total of 192 days, according to Chile's central grid operator. While that may be good for consumers, it's bad news for companies that own power plants struggling to generate revenue and developers seeking financing for new facilities. The main culprit is the northern part of the country, in the Atacama desert. Chile's increasing energy demand, pushed by booming mine production and economic growth, helped spur the development of 29 solar farms, with another 15 planned, on the country's central power grid. Now the nation faces slowing demand for energy as copper production slows amid a global glut, and those power plants are oversupplying a region that lacks transmission lines to distribute the electricity elsewhere.
This is going to be a real challenge to people want to build new renewable sources. Would you want to build a solar plant if it produces energy at a time that you can't sell it, and produces little at times when the prices are highest. (Nice if you want to sell storage systems though).
Why not create some aluminum recycling factory? Those are pretty energy intensive. They could scale their operations based on excess demand. Perhaps even solely to create aluminum-air batteries.
I guess we've known this problem would come along at some point...
With absolutely no knowledge of the technical feasibility of them, how about applying these two solutions?
1. Split Water Into Hydrogen and Oxygen
Could they use the electricity to store energy in the form of hydrogen? This could then be burned in fuel cells to generate electricity more readily, i.e. on demand, perhaps through the night when solar doesn't work? I guess the two issues with this are (i) the volatility/inflammability of hydrogen; and (ii) the fact that burning the hydrogen is exothermic and therefore contributes to warming...
2. Potential Energy Pumps
In the UK we have some minor success, with power stations like Loch Awe in Scotland, in which the turbines can be reversed into electric motors and can be used to pump water up a gradient. To make this work you need 2 lakes, one above the other [i.e. on sides of a mountain]. With a solar surplus in the day you use the energy to pump water from the lower lake to the higher one. When you have an electricity shortfall you allow the process to reverse, using gravity and falling water to generate electricity via hydroelectric power.
Both of these solutions are flawed and, to variable extents, inefficient. But they do work. If we put investment into good R&D on these sorts of challenges today, then they will become more refined with time...
As you mentioned, pumping water up hill requires specific geography - the same as hydroelectric, basically. Hydroelectric is pretty cool, so that's been done in the locations it can be done. It covers 1%-2% of our energy needs. For the US as an example, 48 hours of energy storage would require flooding most of the US west of the Mississippi river. It works on a small scale, can't ever be a primary source of energy.
In 7th grade I wrote a paper about splitting water into hydrogen and oxygen and I was excited about the prospect. Since then, I've learned that hydrogen is a bitch. Without going into details, it's a bitch to store, a bitch to transport, and not particularly efficient. However ...
The general concept of combining hydrogen and oxygen to release energy does work extremely well, if you add one other ingredient. In fact, it is the world's primary method of energy storage and transportation. Along with the hydrogen, you add carbon, creating hydrocarbons. (Combining them the other way around produces carbohydrates, the energy source your body uses). We know hydrocarbons are a very effective way to store and transport energy, and the infrastructure is already in place. Perhaps we could do almost exactly what nature does. Perhaps we could PRODUCE hydrocarbons using atmospheric carbon and solar energy. So the produces turns atmospheric CO2 and H20 into hydrocarbons and oxygen, the car or factory burns the hydrocarbon back into C02 and water, in a cycle. That's exactly what nature does with carbohydrates - plants convert Co2 and H20 into carbohydrate using solar energy, animals convert it back, in a balanced cycle. I know of no reason we couldn't have a similar balanced cycle for hydrocarbons, using solar energy to capture atmospheric C02 into hydrocarbons.