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Largest Sodium Sulfur Battery Powers a Texas Town
separsons writes "The largest sodium sulfur battery in America, nicknamed 'BOB,' can provide enough electricity to power all of Presidio, Texas. Until now, the small town relied on a single 60-year-old transmission line to connect it to the grid, so the community frequently experienced power outages. BOB, which stands for 'Big-Old Battery,' began charging earlier this week. The house-sized battery can deliver four megawatts of power for up to eight hours. Utilities are looking into similar batteries to store power from solar and wind so that renewables can come online before the country implements a smart grid system."
Not based on the $25 million sticker price: that's just bullshit accounting. I'd like to know the Joules expended in the extraction, refining, shipping and construction of this thing, including the energy required by the workers, then let's compare that to the energy that it will actually store and deliver over its working life.
Eventually, we are going to have to start asking these questions about "renewable" generation and storage, because you can only hide a net energy loss in the books for so long, until the fossil fuels that subsidise these energy sinks start to run out.
If you were blocking sigs, you wouldn't have to read this.
They can last about 2,500 complete cycles or 4,800 80% discharge cycles. (From the wikipedia article linked elsewhere). Presuming a power outage once a week requiring 80% discharge, it would last about 90 years, if the number of cycles is the only thing determining its longevity.
That is 10-15 years when used as a night-time backup for solar collection.
This might be useful.
-Todd
Omne ignotum pro magnifico.
This battery should be able to last a very, very long time without losing significant capacity. It's also a big enough battery that it can be refurbished rather than just being tossed when it's used up.
What's the cost of legislation for a nuke plant in the US per mW though? Diesel generators produce the same energy for half the price as nuclear in the kW range, and regulation is slim to none.
moox. for a new generation.
So you're saying instead of smelting metal, making concrete, and paying construction workers to build the battery, it might be more cost effective to pay that same smelting facility, concrete making plant, and construction workers to provide a few hours of power for this town every week or so?
I doubt this project has anything to do with "renewable" but all to do with convenience of not having to lose power for a few hours every few weeks. Sure those few hours may be 10x as expensive as normal, but, eh, you don't have to adjust clocks on all those VCRs every week.
"If anything can go wrong, it will." - Murphy
Let's do the math here.
The article suggests the battery can put out 4 megawatts for 8 hours. So that's 32,000 kilowatt-hours. My electricity here costs about 7 cents a kWh, so that BOB can hold almost $225 worth of electricity. At a cost of many millions, that does not sound like very economical power per kWh!
For example, your basic Honda generator can run for two thousand hours, putting out 1,500 watts, before the little putt-putt engine needs an overhaul. So that's about 3,000 kilowatt-hours for $400. Let's assume the power fails ten times a year, so you'd wear out 10 Honda generators per failure (avg), at a cost of $4000 per, or $40,000 per year. By comparison BOB's cost of financing in itself is going to be at least $3 million a year, not to mention maintenance.
So these poor sods are paying about 75 times as much as they should.
( Not to mention that generators are much more economical in larger sizes )
Somehow I suspect that the costs of Pebble Bed nuclear reactors don't scale up linearly per-kilowatt.
If that was the case, then one could get a "personal" 1kW pebble bed reactor for $1000.
So there must be a "minimum" power value above which the price per kilowatt is close enough to the one you quoted for your argument to make some sense.
Until you can show that 4mW is at or above that "minimum" power value your argument makes no sense.
I am interested in how the battery becomes AC to be distributed. It must be an impressive inverter to go along with the large battery.
Its always amazes me that so few people understand fundamental concepts about the energy that they use. The reporter probably just assumed that the battery is directly connected to the town grid.
new letter/phrase: hex-u means "www"
Call me old-fashioned, but I'd go 100% eco with a gerbil in a wheel or a hand crank if the demand doesn't exceed 4mW.
Not to be pedantic (well, ok, in fact to be ultra-pedantic... so pedantic I find it necessary to point out how pedantic I'm being, and you can't get much more pedantic than that) there's nothing especially 'eco' about gerbils or hand cranks. 'Natural' maybe, but nature is full of incredibly wasteful processes (evolution itself, for example).
I'd like to see us break this bizarre association people have between the industrial use of the most wasteful processes on the planet (natural ones) and ecologically friendly technology.
So at 4 mW (yeah, I got the joke, I just decided to use it to make my incredibly pedantic point) you'd be better off from an ecological perspective going with a radioisotope generator. Salvage some 241Am out of a bunch of smoke detectors and you'd be good to go, and eco-friendly as can be.
Blasphemy is a human right. Blasphemophobia kills.
Well, if oil runs out, the worst option for eletricity generation will be a diesel generator.
Why not? Really, give a reason for one not being able to do that. EROEI is ok, minerals are ok once you adopt a (more expensive) process of refining that uses eletricity instead of oil, mining is ok, transportation is ok. You'll need some bio oils for lubrification, plastics and rubber, but everything quite on the realm of the possible.
Rethinking email
Only one problem with your rosy prediction of the future. It has been apparent for decades now that we need to "wean ourselves off oil" yet our oil consumption rate has only gone up.
One convenient locations...in Africa.