Grid-scale battery based on train cars and gravity

in environment on 2016-05-01 16:48 (#1CEAW)

A California start-up named Advanced Rail Energy Storage (ARES) has a clever idea for storing electrical power at the most extreme scales, e.g. those of the power grid itself. It's a battery of sorts. The scheme include a really big hill and a few railroad cars. Energy to be stored in the system is first used to pull the rail cars via electric locomotives to the top of the hill, where it persists as potential energy. So long as the cars are at the top of the hill, the initial energy expended to get them up there remains trapped within the system. To recover that energy, the cars are simply lowered down the hill, turning built-in motor-generators in the process. This power is collected and then returned to the grid. The system is able to recover 80 percent of the power that it takes in, which is better than pumped-storage hydro (due to evaporation) or most batteries.

Earlier this month, ARES won approval from the Bureau of Land Management for a lease of 156 acres in southern Nevada featuring some train tracks on a hill and connectivity to the greater western US power grid. The 50 megawatts facility is not huge (enough to power 15,000 or so homes) but ARES imagines large regional facilities capable of 2 to 3 gigawatts in the future.

Re: So dry (Score: 1)

by evilviper@pipedot.org on 2016-06-16 01:51 (#1HBD7)

Maintenance is not free, land is not free, having parallel tracks requiring weed control, etc.

Maintenance on a rarely-used train would just be a few hours once per year. Land is extremely cheap a couple hours outside of most any city, and the grid has no problem moving power that distance with minimal loss. Train tracks sprawling across the planet seem to be just fine without active weed control...

Would be slightly impressive if the train cars actually went somewhere and transported something useful, like water.

I they were hauling water up-hill, then unloading it, you'd completely defeat the purpose of this system. A water pump would surely be more efficient, anyhow.

Smarter electricity use and a better grid, capable of transferring power from where it is produced to where is it needed, would do the same more robustly, and probably cheeper too.

Energy storage like this is very much a critical feature of any smart grid. Wind and solar power aren't necessarily producing the most power when demand is highest, and peaking plants have always been very expensive.

Businesses and the public have been largely resistant to changing their energy use patterns. Perhaps the notification and metering technology isn't there yet, or perhaps the incentives aren't significant enough, but either way, controlling "electricity use" doesn't seem to be a viable alternative.