3 ms·
Mine water is not a problem. With an iron weight, water just reduces total MWh capacity by up to 13%. So, you just add 13% more iron. The crane and blocks thin
by ncmncm 4y ago
Mine water is not a problem. With an iron weight, water just reduces total MWh capacity by up to 13%. So, you just add 13% more iron.
The crane and blocks thing obviously will not work. Multiple YT vids explain why, if not clear.
Efficiency is not especially important when generation capacity is cheap. Often something else matters more.
Government people can get along by hiring a engineering consultant to lay out costs, and picking the cheapest alternative.
- aurizon 4y agoA weight that sinks = granite is a lot cheaper than iron. There is an ecology of governments and consultants designed to weed out those that do not bribe.
- ncmncm 4y agoScrap iron is very cheap. But if you use granite, the flooded penalty is 20% instead of 13%. Not a big deal. Could use lead, instead, flooded penalty 9%. The choice of material for the weight is just about which is cheapest.
- aurizon 4y agoTrue, local rock is cheapest - but the structure that you lift has to with stand tens of thousands of haul-up/lower-down cycles = standard blocks with enduring quality. Scrap iron does not pack well, unless melted into standard blocks = $200/tonne or more. Crushed granite and various sizes of graded rock (the MacAdam principal) with close to 5% of voids to which you add 5-7% portland cement, as well as a few rebars and cemented in attachment lugs is what these block are made of. They will have a rebar pattern that prevents fragmentation in there are any cracks over time. AS the cement cures, the cement re=hydrates and creates a void free very strong in compression block. With machine pick-up and place-down that carefully avoids crack-making impacts they can survive tens of thousands of trips - which will probably be 1-2 times/day - as power is needed. A water filled mineshaft would work, but most vertical shafts are 8-10 feet wide and perhaps 16-20 long, as they were usually made with 2 elevators - 1 goes up as 1 goes down. For this application they could fit the shaft. Water might erode and places with bad mix. These shafts can be several thousand feet deep - varies. These built on land pyramids are far wider/deeper = lower height needed for same storage as a deep mine limited in width. Most large mines now use 'trackless mining' = a long spiral highway 30 feet wide and 20 feet high going down at an angle, with rock hauled up by electric carts(huge ones) https://www.google.com/search?q=trackless+mining+wiki&rlz=1C1CHBF_enCA924CA924&sxsrf=ALiCzsZ2rVDPFQWR_uiq4KP1ETMzMLLRSQ%3A1655324254182&ei=Xj6qYujgCoH0tAbg2pKgBA&ved=0ahUKEwjoh6Kxo7D4AhUBOs0KHWCtBEQQ4dUDCA4&uact=5&oq=trackless+mining+wiki&gs_lcp=Cgdnd3Mtd2l6EAMyBQghEKABOgcIABBHELADOg0ILhDHARCvARCwAxBDOgUIABCABDoGCAAQHhAWOggIABAeEA8QFjoHCCEQChCgAUoECEEYAEoECEYYAFDbBlixGWChHmgBcAF4AIABwQGIAYkGkgEDMS40mAEAoAEByAEGwAEB&sclient=gws-wiz https://www.google.com/search?q=trackless+mining+wiki&rlz=1C... I have not seen how one of these surface ones operate, especially with wind/winter and how many of these cement blocks they use get cracked/dropped. Can you imagine an attachment failure at the worst time knocking down multiple blocks? Recovering from that would take days/weeks and the actual occurrence might halt things for a while while regulators sniffed into everything, esp if there were any lives lost?