The best part about geothermal is it's one of the cheapest ways to make electricity, about as much as burning coal, with none of the pollution. Using it for power storage is just the bonus.
Geothermal may beat batteries for energy storage
181–190 of 293 posts
Re: Geothermal may beat batteries for energy storage
#182Earlier quoted context omitted.
> I was always wondering why there are no systems converting the unused electricity in potential energy by moving water to a higher ground There are a bunch of pumped storage facilities around [1]. But they work best at massive scale, so suitable locations are somewhat limited. Plus they are expensive to build and often face environmental protests (similar to building dams). Still, it's a solution I'm a fan of. [1] h…
emphasis on massive scale. Moving 500,000 kg (over 1 million pounds) 7.5 meters (~25 feet aka the height of a house) will give you about 10 kWh of energy. This is equivalent to running a 425W device all day, like a small air conditioner. The relationship is linear. Double the weight or the distance to double the energy. All of the metal at a scrap yard I know of amounts to less than half that weight, for reference. I…
It's not "beyond niche", it accounts for 95%+ of worldwide stored energy and is the de-facto energy storage mechanism that all new battery storage technologies are compared against. It also has round trip efficiency comparable to the li-ion batteries (80-90%), which is incredibly hard to beat.
Re: Geothermal may beat batteries for energy storage
#183Earlier quoted context omitted.
This seems like a (regulated) pricing error. There should be no economic way that a high efficiency turbine produces and distributes electricity to heat homes at a greater than 1:1 ratio compared to storing, pressurizing, and delivering, then burning in irregularly maintained consumer homes. Likely the error is that gas pipes to the house are subsidized (albeit the electrical likely is too, with heat pumps and induct…
"high efficiency" turbines are not all that efficient. Burning gas releases 100% of the available energy as heat. Converting that gas to electricity is Also, electricity from gas is relatively expensive. Other sources like coal or hydro are cheaper, which lowers the average cost of electricity.
But gas turbines should be more efficient than a burner under a boiler or a burner in a furnace.
Yes, solar, wind, hydro, nuclear should be cheaper per unit (coal is not usually cheaper than gas in the US)
Re: Geothermal may beat batteries for energy storage
#184Earlier quoted context omitted.
Huh. We have a 1:1 credit system here in Washington.
Considering solar owners are all pushing electricity onto the grid at the same time, when it is needed the least, such a system doesn't make sense. There are real costs associated with getting rid of all that unwanted energy.
I think solar makes sense for most who use air conditioning. That's a load matched pretty closely to the timing of PV generation.
Here in the Sierra foothills, it's been a blazing hot summer. About 90% of our PV generation powered our home air conditioning. We shipped very little energy to the grid on hot days. And it was awesome to have a comfortable environment without sucking grid power on the days when it hit 113°F.
Re: Geothermal may beat batteries for energy storage
#185Earlier quoted context omitted.
> Using batteries for the grid requires roughly the same amount of batteries as EV’s do EVs have much harder constraints. The most obvious is that they need to move around (requiring high energy density, for both mass and volume); they also need to cope with sporadic charging times, and be reasonably fast to charge. It's very hard to compete with the leading Lithium-ion batteries in this space. Grid storage isn't as…
Yep, it’s very possible that wildly different chemistry or even some other method wins. However, using the same battery chemistry in a cheaper form factor is the worst case. Aka if 2.3 Trillion on EV batteries works then the winner must cost less than 2.3 trillion.
Or have fewer externalities, since that’s never properly priced into anything.
Re: Geothermal may beat batteries for energy storage
#186Earlier quoted context omitted.
emphasis on massive scale. Moving 500,000 kg (over 1 million pounds) 7.5 meters (~25 feet aka the height of a house) will give you about 10 kWh of energy. This is equivalent to running a 425W device all day, like a small air conditioner. The relationship is linear. Double the weight or the distance to double the energy. All of the metal at a scrap yard I know of amounts to less than half that weight, for reference. I…
They are building a lot of them in China https://en.wikipedia.org/wiki/List_of_pumped-storage_hydroel...
Makes sense, it is definitely a useful tool. I just think it is insufficient to act as storage. It can be good at producing variable amounts of Watts on demand but not so good at storing enough Watt-hours to keep things running for very long. I can see a great appeal for it to help with load-balancing for a significant amount of choppiness between supply and demand on the hour timescale.
For something like solar, where we will want to store over half our daily energy production at peak storage (ideally 2-3 days worth I think) - I don't think it holds up. Additionally, it doesnt seem like a good bet as a primary mechanism for either storage or on-demand generation if energy consumption continues to increase due to the rather large coefficients involved for scaling it up.
"The United States generated 4,116 terawatt hours of electricity in 2021"[1]
4,116 TWh/year = 11.2 TWh/day
The storage capacities for the largest items listed on the wiki is on the magnitude of GWh. The scale goes kilo-, Mega-, Giga-, then Terra. So we are talking about a need on the order of a thousand pumped storage facilities per country. The US would need over 50 of them per state (on average) in order to keep everything running without production for 24 hours. Doesnt matter how many solar panels we have, if we get 1 dark day then we would run out of power. If we tried to rely on solar entirely, we'd also still need very roughly half that amount of storage just to get through the night.
lithium batteries are obviously much better suited for overnight storage, but I have no idea what the numbers are on how much lithium is physically available to use as such storage.
If we want to get on the order of monthly to yearly storage to allow, for example, solar panels in alaska to provide enough energy for a resident to get through months of darkness - I have no idea what the leading storage options are, probably lithium still
[1]https://www.statista.com/statistics/188521/total-us-electric...
Re: Geothermal may beat batteries for energy storage
#187Earlier quoted context omitted.
This reminds me a lot of the Earthship community in the middle of the desert, which always focusses on smart ways of reusing water for different purposes, and by not wasting water as much as possible. The houses usually have a clean/grey/blackwater + a rainwormbox system to process fecals and reuse it for growing plants. Their air conditioning system is basically just a pipe in the ground where the hot air flows thro…
> Why there are no water storages on the roof. Quick math - 100 gallons of water 15 meters up off the ground has enough potential energy to run a microwave for 30 seconds. Gravitational storage is pathetically weak. It only makes sense on massive, massive scales. In a residential setting, the storage will never outweigh the extra cost and risk of having so much water on your roof.
No post body was provided.
Re: Geothermal may beat batteries for energy storage
#188Earlier quoted context omitted.
> They’re so efficient and work well at low temps now. Can someone provide me model numbers for these heat pumps that “work well” at low temperatures? I’ve been through more than a few over the decades and currently have a Trane from last year and yep, still doesn’t hold up very well once the temperature hits freezing. Don’t get me wrong, I like heat pumps, but my eyes roll into the back of my skull when I hear over…
If you actually live in an area where temperatures drop below -30C regularly, you might want to consider a ground source heat pump. They are a bit more expensive than the typical air source heat pumps since there's some digging involved, but for a new house they aren't that much more expensive since there's already digging for electricity, plumbing, etc. For example ground source heat pumps are getting quite popular…
Who’s talking about -30C? I’m talking about 32F, or 0C. I’ve yet to be impressed by a heat pump once the temperature gets at or especially below freezing.
Geothermal heat pumps are great but at least in the US they are wildly expensive compared to traditional ones. You either need a large lot for horizontal laying of the pipe or a DEEP hole if going vertical ($$$). Plus they’re uncommon enough that contractors are happy to charge a serious premium.
Re: Geothermal may beat batteries for energy storage
#189Earlier quoted context omitted.
emphasis on massive scale. Moving 500,000 kg (over 1 million pounds) 7.5 meters (~25 feet aka the height of a house) will give you about 10 kWh of energy. This is equivalent to running a 425W device all day, like a small air conditioner. The relationship is linear. Double the weight or the distance to double the energy. All of the metal at a scrap yard I know of amounts to less than half that weight, for reference. I…
It's not "beyond niche", it accounts for 95%+ of worldwide stored energy and is the de-facto energy storage mechanism that all new battery storage technologies are compared against. It also has round trip efficiency comparable to the li-ion batteries (80-90%), which is incredibly hard to beat.
95% stored energy by what measurement? See my other comment. It is not accessible to everyone, nor can it be made accessible to everyone, and the current storage capacity is a marginal fraction of what we actually use. It's a short term load balancing tool that operates within a small energy window.
Re: Geothermal may beat batteries for energy storage
#190Earlier quoted context omitted.
This reminds me a lot of the Earthship community in the middle of the desert, which always focusses on smart ways of reusing water for different purposes, and by not wasting water as much as possible. The houses usually have a clean/grey/blackwater + a rainwormbox system to process fecals and reuse it for growing plants. Their air conditioning system is basically just a pipe in the ground where the hot air flows thro…
> Why there are no water storages on the roof. Quick math - 100 gallons of water 15 meters up off the ground has enough potential energy to run a microwave for 30 seconds. Gravitational storage is pathetically weak. It only makes sense on massive, massive scales. In a residential setting, the storage will never outweigh the extra cost and risk of having so much water on your roof.
One minor but interesting exception - farmers have historically often put domestic water tanks on top of towers to ensure even water pressure. Direct pumping leads to cycles where the pressure in the system rises and falls as the pump cycles on and off, which is very unpleasant if you’re trying to take a shower!
I believe modern off-grid home water pumps use more sophisticated motor control to avoid the need for the raised tank.