Grid-scale battery based on train cars and gravity

by
in environment on (#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.
Reply 6 comments

So dry (Score: 2, Informative)

by fishybell@pipedot.org on 2016-05-01 20:49 (#1CEV7)

Interesting. It's essentially a dry version of an old technology. Quite likely cheaper and more environmentally friendly to boot.

Re: So dry (Score: 1)

by reziac@pipedot.org on 2016-05-02 06:29 (#1CFX5)

The reservoirs used for hydro power are very enviro-friendly indeed; they hugely benefit wildlife, and probably do a lot to recharge aquifers since the water sits there long enough to soak in rather than just running past.

Regardless... seems to me this could be adapted to small-scale and local, to use any hill in parallel with existing roadways.

Re: So dry (Score: 2, Interesting)

by evilviper@pipedot.org on 2016-05-03 03:26 (#1CK09)

The reservoirs used for hydro power are very enviro-friendly indeed; they hugely benefit wildlife,
That's really not true. There's a huge amount of information out there on the environmental damage dams cause, like driving salmon and other species to near-extinction. It's been a cause ci©li¨bre in recent years to destroy old and unnecessary dams everywhere that is remotely practical.

"Sierra Club California does not support any proposal that provides funding for the construction of new dams or surface storage in California."

"2014 was a monumental year for dam removal projects. A record-setting 72 dams were removed across 19 states, restoring hundreds of miles of river, and last year's Patagonia-produced film DamNation raised even more awareness about the environmental impact of defunct dams that block salmon and other fish from their upriver breeding grounds." http://sierraclub.org/sierra/2015-2-march-april/green-life/3-dam-detonation-videos-prove-going-green-blowing

Providing big watering-holes for wild life in the Nevada desert is not necessarily an environmental benefit at all. Instead it can bring in more large wild life, which should not naturally be there, which then displaces and kills the native desert species. And destroying dozens or hundreds of square miles of land and habitat by flooding it is never going to be looked on as environmentally friendly. Those kinds of projects tend to be supported by hunters, rather than environmentalists.

Re: So dry (Score: 1)

by bryan@pipedot.org on 2016-05-02 23:02 (#1CJRH)

Plus you don't have to worry about the rail cars evaporating.

Re: So dry (Score: 1)

by olof@pipedot.org on 2016-06-15 07:17 (#1H883)

This seems like a very large investment for a very small gain.
Maintenance is not free, land is not free, having parallel tracks requiring weed control, etc.
Most areas don't have large areas of land available for free, especially those areas where people actually live.
Would be slightly impressive if the train cars actually went somewhere and transported something useful, like water.
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.

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.