3 ms·

Fusion can and hopefully will be competitive in the near future, but gravity based storage is just not possible to scale unless we're talking about massive hydr

by mateo1 4y ago

Fusion can and hopefully will be competitive in the near future, but gravity based storage is just not possible to scale unless we're talking about massive hydroelectric dams. I didn't know about energy vault and yeah the investment amount they managed to get is insane. Centrifugal energy storage can be used as a short term buffer somewhat economically for variations in demand, but not actual storage. Thankfully natural gas and other fossil fuels store just fine as they are, and peaker plants are very cheap as they're usually just the old low efficiency plants, available at essentially zero capital cost.

ncmncm 4y ago
There is no possibility of fusion becoming competitive. A fusion plant would cost at least 10x fission, and fission is itself very far from competitive. As costs for renewables continue falling, that target gets always further out of reach. Centrifugal storage could be useful for a few seconds, perhaps to smooth over sudden spikes. But it has been well-understood for over a century, and not used yet, so that is unlikely to change. Natural gas and other fossil fuels are the problem we are trying to solve, so they cannot count as part of a solution. For the present, NG must be used when renewables fall short, because any storage we built out now would have to be charged up from fossil fuels anyway, as renewables do not exceed demand yet. Practical storage will turn out to be based on an eclectic mix of air pressure (underground or undersea), liquified nitrogen, chemical synthesis (hydrogen, ammonia), hydro (conventional pumped surface, and underground and undersea variations), plus some small amount of batteries (liquid metal, iron). The first few are attractive because they are compatible with existing gas furnaces. Hydro is attractive because it is very mature. Chemical synthesis is attractive because once local tankage is full, any surplus power generated can be turned into revenue, and any shortfall in storage can be made up by importing more. One more possibility is subsea buoyancy; an air bladder or rigid air tank is drawn toward a pulley anchored to the sea floor, yielding power when it is allowed to rise again.
bokohut 4y ago
I am legitimately curious as to why there is such an adverse acceptance to gravity storage? This is already done in the U.S. West in running large density mass trains up hillsides and Gravitricity over the pond has a functioning model using old mine shafts. As an entrepreneurial tech founder I comprehend oh too well that until someone proves "it works" there will always be nonbelievers even though the math and physics agree. Maybe it is inherent human nature to not believe something until it is seen but in this era we also will have countless which do not believe even when it is proven. The planning is the easy part and the math checks out, mhg=pe, execution is what is difficult and all that matters.
- ncmncm 4y ago
  Pumped hydro is gravity storage. It works. Running train cars loaded with rock aggregate up and down disused mountain rail tracks could be a good idea, depending on how you get the power out (third rail?), but seems like it would be expensive to keep working. Running a multi-thousand-ton weight up and down a disused mineshaft seems a certain winner, anywhere you happen to have such a shaft at hand. Pumping air into a bag anchored to the ocean floor. Winching an air tank down to a pulley anchored to the ocean floor. Winners in energy storage will be distinguished from the field of failures along axes of cost, secondary usefulness, compatibility with existing infrastructure, service lifetime, energy capacity, power capacity, environmental impact, simplicity, and efficiency. For example, synthetic chemical and liquified air media excel at secondary usefulness, compatibility with existing gas turbines, and cheap tankage (unlimited capacity), at the expense of cost and efficiency. Their main cost is for synthesis capacity, measured in watts. Low efficiency is tolerable in exchange for other merits. Energy Vault is a certain failure on the basis of cost alone, even without considering its other low scores. Constructing condominiums for concrete blocks is just extremely expensive, even before counting predictably very high maintenance cost, for minuscule storage capacity. Simplicity is the most frequently neglected, but often most valuable quality. The best storage systems will have just one moving part used for both storing and extracting energy. Next best, two.
  - bokohut 4y ago
    Thanks for your time in the succinct reply. They all work, you just need mass and height given a surplus of renewable power from any source. Last I checked we have junkyards filled with oxidizing metal that could be put to "potential" work as mass, not to mention all the other precious metals which could be reclaimed as people seem to forget we pulled them from the ground to begin with. Height is accomplished using the same materials salvaged from the junkyards to be used as structure in a different remanufactured form. Hopefully gravity doesn't change because then all of this is meaningless anyway. Efficiency doesn't really matter because nothing I am aware of is 100% efficient in energy and if the source is renewable then the loss is always made up in time, something people have no patience for today it seems. The CAPEX cost may be high but with correct design the OPEX cost will be low and functional unit lifetime correlates to the specific lift/generation device and that is where your simplicity reference is key. It always comes back around to cost but when the power goes out what are people willing to pay? I have contacts that lived through the Winter Texas outage and the stories impact deeply and it of course will not happen again. Oh wait, last week 6 plants totaling 2.6 GW went offline from the spike based on May heat and certainly June, July and August will be cooler. And what about all of those devices that require electricity to keep various mammals alive, humans included? My experiences reflect that few people on this planet are proactive, I can only hope those with crazy ideas working toward the energy problem find the needed traction in proving solutions that work to our global energy issues. If we do not solve the energy issue in a clean manner we are certain to be unable to solve the carbon issue which will need that very energy to return all the carbon we have already released and more. Your assertion of simplicity is correct and this is the best outcome I can hope for. I'll shoot for one, maybe two but whatever the outcome, simplicity will always be top of mind. I am no expert by any means yet thanks again for the motivating feedback.

by mateo1 4y ago

ncmncm 4y ago

There is no possibility of fusion becoming competitive. A fusion plant would cost at least 10x fission, and fission is itself very far from competitive. As costs for renewables continue falling, that target gets always further out of reach. Centrifugal storage could be useful for a few seconds, perhaps to smooth over sudden spikes. But it has been well-understood for over a century, and not used yet, so that is unlikely to change. Natural gas and other fossil fuels are the problem we are trying to solve, so they cannot count as part of a solution. For the present, NG must be used when renewables fall short, because any storage we built out now would have to be charged up from fossil fuels anyway, as renewables do not exceed demand yet. Practical storage will turn out to be based on an eclectic mix of air pressure (underground or undersea), liquified nitrogen, chemical synthesis (hydrogen, ammonia), hydro (conventional pumped surface, and underground and undersea variations), plus some small amount of batteries (liquid metal, iron). The first few are attractive because they are compatible with existing gas furnaces. Hydro is attractive because it is very mature. Chemical synthesis is attractive because once local tankage is full, any surplus power generated can be turned into revenue, and any shortfall in storage can be made up by importing more. One more possibility is subsea buoyancy; an air bladder or rigid air tank is drawn toward a pulley anchored to the sea floor, yielding power when it is allowed to rise again.

bokohut 4y ago

I am legitimately curious as to why there is such an adverse acceptance to gravity storage? This is already done in the U.S. West in running large density mass trains up hillsides and Gravitricity over the pond has a functioning model using old mine shafts. As an entrepreneurial tech founder I comprehend oh too well that until someone proves "it works" there will always be nonbelievers even though the math and physics agree. Maybe it is inherent human nature to not believe something until it is seen but in this era we also will have countless which do not believe even when it is proven. The planning is the easy part and the math checks out, mhg=pe, execution is what is difficult and all that matters.

ncmncm 4y ago
Pumped hydro is gravity storage. It works. Running train cars loaded with rock aggregate up and down disused mountain rail tracks could be a good idea, depending on how you get the power out (third rail?), but seems like it would be expensive to keep working. Running a multi-thousand-ton weight up and down a disused mineshaft seems a certain winner, anywhere you happen to have such a shaft at hand. Pumping air into a bag anchored to the ocean floor. Winching an air tank down to a pulley anchored to the ocean floor. Winners in energy storage will be distinguished from the field of failures along axes of cost, secondary usefulness, compatibility with existing infrastructure, service lifetime, energy capacity, power capacity, environmental impact, simplicity, and efficiency. For example, synthetic chemical and liquified air media excel at secondary usefulness, compatibility with existing gas turbines, and cheap tankage (unlimited capacity), at the expense of cost and efficiency. Their main cost is for synthesis capacity, measured in watts. Low efficiency is tolerable in exchange for other merits. Energy Vault is a certain failure on the basis of cost alone, even without considering its other low scores. Constructing condominiums for concrete blocks is just extremely expensive, even before counting predictably very high maintenance cost, for minuscule storage capacity. Simplicity is the most frequently neglected, but often most valuable quality. The best storage systems will have just one moving part used for both storing and extracting energy. Next best, two.
- bokohut 4y ago
  Thanks for your time in the succinct reply. They all work, you just need mass and height given a surplus of renewable power from any source. Last I checked we have junkyards filled with oxidizing metal that could be put to "potential" work as mass, not to mention all the other precious metals which could be reclaimed as people seem to forget we pulled them from the ground to begin with. Height is accomplished using the same materials salvaged from the junkyards to be used as structure in a different remanufactured form. Hopefully gravity doesn't change because then all of this is meaningless anyway. Efficiency doesn't really matter because nothing I am aware of is 100% efficient in energy and if the source is renewable then the loss is always made up in time, something people have no patience for today it seems. The CAPEX cost may be high but with correct design the OPEX cost will be low and functional unit lifetime correlates to the specific lift/generation device and that is where your simplicity reference is key. It always comes back around to cost but when the power goes out what are people willing to pay? I have contacts that lived through the Winter Texas outage and the stories impact deeply and it of course will not happen again. Oh wait, last week 6 plants totaling 2.6 GW went offline from the spike based on May heat and certainly June, July and August will be cooler. And what about all of those devices that require electricity to keep various mammals alive, humans included? My experiences reflect that few people on this planet are proactive, I can only hope those with crazy ideas working toward the energy problem find the needed traction in proving solutions that work to our global energy issues. If we do not solve the energy issue in a clean manner we are certain to be unable to solve the carbon issue which will need that very energy to return all the carbon we have already released and more. Your assertion of simplicity is correct and this is the best outcome I can hope for. I'll shoot for one, maybe two but whatever the outcome, simplicity will always be top of mind. I am no expert by any means yet thanks again for the motivating feedback.