4 ms·
Am I right in thinking 9.8 joules per kilo per metre * 20,000,000 kilos * 26 metres = 5,096,000,000 joules or ~1.4 MWh? That seems low, so I must be missing so
by closewith 3y ago
Am I right in thinking 9.8 joules per kilo per metre * 20,000,000 kilos * 26 metres =
5,096,000,000 joules or ~1.4 MWh?
That seems low, so I must be missing something?
- Jabbles 3y agox10 -> 200,000,000 kilos
- closewith 3y agoGood catch. Even so, 14 MWH is only about $3,000 at Panama prices. That's nothing compared to the cost of transit. Obviously there'd be extreme capital costs and engineering/environmental challenges, but far less than an equivalent train. After all, the canal moves more tonnage daily than the proposed train could in a year.
- AndrewDucker 3y agoPotential energy is actually pretty cheap. Which makes it unfortunately useless for energy storage (lifting 1 ton by 1m is about the same as an AAA battery)
- cubefox 3y agoWhy is this useless though? Space constraints?
- falserum 3y agoYes. (Space inefficiency)
- cubefox 3y agoBut in some countries there are large areas of undeveloped land, so lots of space to store energy.
- AndrewDucker 3y ago1,000kg by 1m is about 3Wh. A Tesla Powerwall is 13.5 kWh. So you either need 4,500 tons by 1m, or 1 ton to be raised 4.5km, or 67 tons by 67m. To match a single home's battery backup. Doing that for cheaper than $2,000. Which is what a battery that size costs in large quantities. That sounds pretty unlikely.
- cubefox 3y agoDam reservoirs can reach a pretty massive volume. The Hoover dam holds 35.000 km^2 of water (that's 35 billion tons if I'm not mistaken) according to Wikipedia. I'm not sure how much of that can be raised by how much.
- AndrewDucker 3y agoOh yeah, water works well, because you can raise it very efficiently. It's a very well worked through technology. Moving billions of tons of concrete vertically is a lot harder. (Most dams also supply their own water. Hydro storage is trickier, and needs you to build pumping systems, and sometimes to hollow out mountains)
- falserum 3y agoHydro dams prove that it’s possible, but they require being blessed by geography/topology.