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Old Electric-Car Batteries Put Into Service For Home Energy Storage
Hugh Pickens writes "Josie Garthwaite writes that old electric car batteries degraded below acceptable performance levels for autos still have enough life to serve the grid for at least ten years with a prototype announced by GM and ABB lashing five Chevy Volt battery packs together in an array with a capacity of 10 kilowatt-hours — enough to provide electricity for three to five average houses for two hours. 'In a car, you want immediate power, and you want a lot of it,' says Alexandra Goodson. 'We're discharging for two hours instead of immediately accelerating. It's not nearly as demanding on the system.'" (Read on, below.)
Pickens continues: "Deployed on the grid, community energy storage devices could help utilities integrate highly variable renewables like solar and wind into the power supply, while absorbing spikes in demand from electric-car charging. 'Wind, it's a nightmare for grid operators to manage,' says Britta Gross, director of global energy systems and infrastructure commercialization for GM. 'It's up, down, it doesn't blow for three days. It's very labor-intensive to manage.' The batteries would allow for storage of power during inexpensive periods for use during expensive peak demand, or help make up for gaps in solar, wind or other renewable power generation. One final advantage of re-using electric car batteries is that the battery — the most expensive part of an electric car — remains an asset beyond its useful life in the vehicle. 'If there is a market in stationary power for spent batteries, consumers could recognize this as an increased resale value at end of life, however small,' says Kevin See."
Your house uses more than 10kw? I really have to ask, what the heck are you doing??
I have a modest 4x2 house, with a stay-at-home wife and 2 kids. Big screen TV, and all the other creature comforts and I wouldn't even come close to use 10Kw.
In this instance I have to say 'you're doing it wrong'.
In USA they do not have much use. For emergencies like Sandy, FEMA should simply develop a plan to send the fuel trucks from the army and drive around the affected neighborhoods and dispense fuel for cars in the drive way of homes. The municipalities can collect the cost of the fuel from the homeowners through utility bills later. And the collected money can be considered emergency grants from the federal govt to the municipalities. Once you have an assured supply of fuel in an emergency, we can use the hundreds of thousands of power plants that are already present in these locations.
The hundreds of thousands of powerplants are typically four cylinder gasoline engines, and a good portion of them are six and eight cylinders, the automobile engines. Presently the alternator is sized to provide just enough electric power for the car. If we design a generator that runs at the right RPM, and connection kits that will allow it to be coupled to an car engine it would be very helpful. I am thinking of some kind of frame, a new serpentine belt, or some way to work off the belt driving the alternator. If FEMA funds the R&D to create these kits, builds them and stocks them, they can be deployed in an emergency.
In an emergency so many people would happily stay at home and avoid driving around, if they can. But they are all forced to run around looking for food, gas and water. Municipalities should develop emergency plans where their residents simply text to some known number information like, "running short of water/food/gas", "Medical attention needed", "Number of young children = XX". They should consolidate and send around FEMA trucks to bring food/water/gas to them. If people have the peace of mind, they will stay home and let the roads free for people with real emergencies.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
I'm sure all those houses that burned down in Queens had piles of batteries laying around, that's what caused the fire. I'm also sure it's impossible for a normal car without a HV battery pack to catch fire for any reason, including flooding.
Meanwhile, two dozen all-electric Nissan LEAFs failed to catch fire after the 2011 tsunami that hit Japan.
(Maybe the Fisker Karma is just a piece of shit. Don't blame the HV battery.)
=Smidge=
This is for grid-level storage, not in-your-home backup. Space and weight are a distant concern compared to cost.
There is an important concept called demand (or load) leveling. How much electricity the grid demands changes significantly over the course of the day, so you much design your power plants and infrastructure to handle the peak load. However the peak load is only experienced a small fraction of the time, meaning you are considerably overbuilt for maybe 16 to 18 hours of the day - especially late at night when most people sleep. The problem is so severe that many utility providers offer Time-Of-Use rates where electricity during off-peak hours is considerably cheaper (and on-peak considerably more expensive) to encourage people and businesses to use less during the day and more at night.
Batteries connect to the grid though a charge controlling inverter - a single piece of equipment. During the off-peak hours they absorb excess energy by charging, meaning the generation equipment runs more efficiently and more economically. During peak hours they release the energy decreasing the demand on the system so it doesn't have to be so overbuilt and therefore less expensive to maintain and operate.
The process of shifting load from peak to off-peak is sometimes referred to "filling the bathtub" and utility providers love it since it makes their lives much easier. Battery storage is a great way to achieve this at the grid level and anyone who manages to develop a cost effective solution stands to make a LOT of money selling and installing such systems.
=Smidge=
They do. Newer units are starting to use inverter-driven compressor motors for variable speed. The actual reason to use them is higher efficiency while operating, but a very nice side-effect is virtually no inrush.
I spend time on several off-grid / renewable-energy forums, and one of the biggest changes for off-grid homes recently is that you can buy inverter-driven mini-split AC units that can cool a (small) home from solar / battery banks without any issue. Several people set the unit to "low" in the morning, and let it run all day, draws only 300W. Won't keep the house cold, in fact the temp slowly climbs through the day, but only to 78 instead of 85-90.
I have a portable AC unit (roll-around, with the flex hose to exhaust hot air out the window) that uses an inverter. 9000 BTU, draws 1200W or so while running, starts just fine with a little Honda EU2000i generator (1600W continuous, 2000W peak). The 9000 BTU mini-split (standard compressor) in my server closet won't even try to start, the generator just bogs down.
Here's a wild idea I'll just throw out.
Don't use the microwave, kettle, washing machine, electric oven, flatscreen TV, tumble dryer and PC at the same time when you're running your generator.
Crazy I know, but it might work.