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Geothermal may beat batteries for energy storage

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Re: Geothermal may beat batteries for energy storage

#51

Post by mschuster91 »

Schroedingersat wrote: post #26
nullish_signal wrote: post #2

One wonders what the limits of "Thermal Heat" are from small "wells"(???) up to the heat content of the Earth's ore (Heat relative to sea level) How much heat is generated by Earth's gravity onto itself? How "renewable" is Geothermal energy, truly?

The total budget for any given power source is surprisingly close to 100TW. Geothermal, you'd cool the crust and have to drill far deeper than is possible to exceed 50TW for long. Wind, if you exceed somewhere in the 1-10W/m^2 you slow down the wind and create turbulence. Solar, if you use more than ~1% of the land you're radically altering the albedo and habitat (so maybe up to 200TW). Fossil fuels create GHG and ru…

> Solar, if you use more than ~1% of the land you're radically altering the albedo and habitat

Both of these may actually turn out to be beneficial. Putting up solar panels above agricultural land ("Agri-PV") is not just avoiding clobbering up arable land with PV panels, but also has benefits for the plants [1]: they need less water because less sun directly hits the plants and heats up the soil which means both more resilience in drought periods and more capacity to regenerate groundwater planes, and the soil erosion from wind is reduced as well.

I wonder if putting up panels in the desert could help out de-desertification efforts as well for the same reasons.

As for albedo - given that we're already having issues with global warming, it is not that far-fetched to say that solar radiation being reflected off to space is a good thing overall.

[1] https://www.ise.fraunhofer.de/content/dam/ise/de/documents/i...

Re: Geothermal may beat batteries for energy storage

#52

Post by rnhmjoj »

jbay808 wrote: post #43
rnhmjoj wrote: post #41

Earlier quoted context omitted.

> But converting it back to electricity is typically less than 50% efficient. It's generally much much worse than 50%. Say that you used a resistor to heat the water in a (perfectly insulated) boiler and want to know how much useful work you can extract from it, ideally. The answer is given by the exergy efficiency, which can be computed by attaching an imaginary heat engine to it, integrating the infinitesimal works…

> Say that you used a resistor to heat the water If you're looking to maximize round trip efficiency, this is probably not a good starting point. Better to use a heat pump, as mentioned elsewhere.

Ok, I see your point now.

Re: Geothermal may beat batteries for energy storage

#53

Post by rjmunro »

majou wrote: post #36
tyfon wrote: post #34

There is a school close to where I live that does something like this. During the summer they heat the bedrock using solar panels (thermal and electric via a heapump) to heat the bedrock far down using water pipes. In winter they extract this energy for heating, electricity and hot water making the school self sufficient for energy. Here is a write-up from the municipality about it, but it's in Norwegian https://www.…

Same idea in Alberta: http://dlsc.ca/borehole.htm

And at the Blavatnik School of Government building in Oxford: https://www.bsg.ox.ac.uk/about/our-building

Re: Geothermal may beat batteries for energy storage

#54

Post by macinjosh »

swayvil wrote: post #30
nicoburns wrote: post #28

Earlier quoted context omitted.

I'm not convinced competition is a euphemism for fighting. Competition can be friendly.

You got any examples of "friendly, nonfighting type competition" in the business world?

https://www.cnet.com/tech/tech-industry/microsoft-to-invest-...

Re: Geothermal may beat batteries for energy storage

#56

Post by manholio »

Retric wrote: post #16
jillesvangurp wrote: post #7

Interesting option. It's all about the cost and efficiencies in the end. Converting electricity into heat and then back into electricity is a lossy process that is constrained by the second law of thermodynamics. Basically generating heat is easy and efficient. But converting it back to electricity is typically less than 50% efficient. Basically, it's several energy conversions in one process: you use electricity to…

Using batteries for the grid requires roughly the same amount of batteries as EV’s do. A 100kWh battery pack for a car * 1,000 charge cycles / 25 years = 4,000 kWh of battery per year * ~290 million cars. That’s enough to store almost 1/3 of all current electricity used in the US while ignoring busses and farm equipment etc. Of course actual cost depends on how much storage we need and future battery prices but addin…

This is never going to happen. As a car owner, you are in a market competing with large providers of grid scale storage, that have large purchasing power, control over the battery chemistry and finer specifications of their hardware which is made to order for their needs etc. Meanwhile, you have a mobility-optimized low weight battery that has a single, monopoly supplier that will very likely treat the spare parts market as a profit center 5 years down the road.

You will never be able to compete because you cannot differentiate, the product is fungible so mass always wins. It's essentially the bitcoin mining rig drama, the going was good until large scale mining operations were set up, with optimized ASICs etc. After that, good luck destroying your graphics card and car battery for pennies on the dollar.

Re: Geothermal may beat batteries for energy storage

#57

Post by helloooooooo »

ncmncm wrote: post #47

This is an example of "how can we keep X relevant in a world where it is not?" Geothermal is falling away because maintaining a steam turbine is expensive. There are plenty of efficient storage options that don't depend on a steam turbine. Those are favored except where the storage medium is also a transportable, valuable product, as for ammonia. (Ammonia is burned in combined-cycle turbines already built to burn NG.…

It depends what you want to use the geothermal heat for. In Norway, in the winter, a lot of the energy use is going to be heating. Geothermal heating systems are quite common in northern and don’t require lossy conversion

Re: Geothermal may beat batteries for energy storage

#60

Post by raphaelj »

manholio wrote: post #56
Retric wrote: post #16

Earlier quoted context omitted.

Using batteries for the grid requires roughly the same amount of batteries as EV’s do. A 100kWh battery pack for a car * 1,000 charge cycles / 25 years = 4,000 kWh of battery per year * ~290 million cars. That’s enough to store almost 1/3 of all current electricity used in the US while ignoring busses and farm equipment etc. Of course actual cost depends on how much storage we need and future battery prices but addin…

This is never going to happen. As a car owner, you are in a market competing with large providers of grid scale storage, that have large purchasing power, control over the battery chemistry and finer specifications of their hardware which is made to order for their needs etc. Meanwhile, you have a mobility-optimized low weight battery that has a single, monopoly supplier that will very likely treat the spare parts ma…

Couldn't scheduling the EV charge when the demand is low while production is high help a lot balancing the grid, at basically no cost for the EV owner?

Let's say I have a EV with a smart charger that will keep the vehicle at least 60% charged, but charge up to 100% when the energy price is low (e.g. during the night).

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