Six Electric Cars Can Power an Office Building

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Six Electric Cars Can Power an Office Building

Posted by timothy on Thursday December 12, 2013 @05:18AM from the sinks-and-sources dept.

cartechboy writes "How many Nissan Leafs does it take to power an office building? The answer, it turns out, is six. Nissan is the latest Japanese automaker to explore electric "vehicle-to-building" setups, this time with impressive results. The company started testing its latest system at the Nissan Advanced Technology Center in Atsugi City, Japan, during the summer. It found that just six Leafs plugged in to the building's power supply allowed it to cut peak-hour electricity use by 2 percent. Annualized, that's a savings of half a million yen (about $4,800 US) in electricity costs. How it works: The building pulls electricity from the plugged-in vehicles during peak-use hours, when power is most expensive, and then sends the power back to recharge the cars when grid prices fall. Nissan says the system is set up to ensure the cars are fully charged by the end of the workday. (Is this a devious secret way to make sure workers stay until a certain time?) Next up: Why not just do this using batteries--never mind the cars?"

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Why not batteries by Anonymous Coward · 2013-12-12 05:21 · Score: 3, Insightful

The batteries in a Leaf are a significant fraction of the price, few business want to spend $120k on batteries, when they can get them for 'free' from their workers.
1. Re:Why not batteries by Mr+D+from+63 · 2013-12-12 05:29 · Score: 4, Insightful
  
  few business want to spend $120k on batteries.
  I wonder how much power they would save by investing $120K in energy efficiency improvements? My guess in >2%
2. Re:Why not batteries by VernonNemitz · 2013-12-12 05:32 · Score: 5, Insightful
  
  Not to mention the well-known fact that batteries have a limited number of discharge/recharge cycles. So, when the batteries in the cars eventually fail, the car-owners have to pay to replace them, not the building-owners.
3. Re:Why not batteries by Shoten · 2013-12-12 05:41 · Score: 3, Insightful
  
  The batteries in a Leaf are a significant fraction of the price, few business want to spend $120k on batteries, when they can get them for 'free' from their workers.
  The cost of the batteries is small in comparison to maintenance. Managing the batteries means hiring someone with that knowledge or paying for training/other development to get it in-house...at which point, those people would become more desirable on the job market as more buildings installed battery systems, increasing cost of retaining that talent. Then there are the business processes that need to be developed, the provisioning of a room to store them (and OSHA/building code concerns around a room full of batteries, which is no minor thing), and so on.
  Or, they can just use the cars parked outside, offloading all of that effort to the owners of the cars.
  
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4. Re:Why not batteries by TheCarp · 2013-12-12 05:50 · Score: 4, Insightful
  
  well the problem, of course, is that the savings were less than 5k/year. That is less than 1k/year/car
  This doesn't leave much room to both benefit the company and provide much bonus before you even figure that this may decrease battery life span. Of course, it also has to be offset by the fact that its also a "top off", presumably the cars drove in, so are not fully charged at the start of the day.
  Maybe it works out, but its not a lot to work with for starters.
  
  --
  "I opened my eyes, and everything went dark again"
5. Re:Why not batteries by bondsbw · 2013-12-12 06:06 · Score: 3, Interesting
  
  If the car owner does all charging at the office, the cost of electricity would offset at least some of the cost of replacing the batteries. But I don't know that it would be worth it. This blog post suggests that the average cost per month of electricity is less than $50 for fairly average use, but the battery replacement program for the Leaf is $100 per month.
  Then again, the car owner would have to replace their battery after so much usage anyway regardless of where it is being charged, so assuming the employer's usage causes about twice as many recharge cycles, the employee might just break even.
  Meanwhile the business gets a win by fully charging the cars when at non-peak usage, say around $0.05/KWH, and fully discharging during peak usage, say around $0.45/KWH, even if they have to supply twice as much energy to the cars as they use to power the office. (I pulled those $/KWH numbers from a post below; I have no clue if they are legitimate.)
  I probably wouldn't participate in this program unless the employer provided a bonus incentive.
  
  --
  All my liberal friends think I'm a conservative, all my conservative friends think I'm a liberal.
6. Re:Why not batteries by bob_super · 2013-12-12 06:15 · Score: 3, Interesting
  
  They just need to use the Renault clone of the Nissan. You get the same battery but the car owner leases it from Renault, so they are the ones stuck with the cost extra failing batteries (and will certainly not pass it down to customers, right...).
7. Re:Why not batteries by Anonymous Coward · 2013-12-12 06:29 · Score: 5, Interesting
  
  There are companies that will do this. I worked for one (that I shall not name). Basically, the company would audit the business's energy usage and come up with a way to save energy (efficient HVAC, lighting, electrical, low-power standby etc). Then, they would make a proposal to split the cost in savings. So all the money is fronted and the business receiving the service pays nothing. The net result is one company saves money, the other earns a profit from a portion of the savings. Win Win.
8. Re:Why not batteries by Anonymous Coward · 2013-12-12 06:59 · Score: 4, Insightful
  
  The other problem is what happens in the event of an emergency (wife goes into labor, kid gets suspended at school, etc) and you don't have a full charge due to the building syphoning power off intending to put it back by the end of the day.
9. Re:Why not batteries by roc97007 · 2013-12-12 07:47 · Score: 3, Interesting
  
  One of the taller buildings close to where I work has six windmills mounted on top. You can often see them twirling away. The local alternative paper did an article on them once. Apparently the building receives up to 4% of their total energy from the windmills. This is a LONG way from "windmill powered buildings", (although is a higher percentage than what I expected) but it does serve another important purpose: From most of downtown, you can see that the building owners have put up windmills. This is apparently important enough that the actual savings wasn't a consideration.
  
  --
  Oliver's law of assumed responsibility: If you're seen fixing it, you will be blamed for breaking it.
Screw that. by Anonymous Coward · 2013-12-12 05:21 · Score: 3, Insightful

This sounds like it would decrease the battery lifetime of my car. Unless I'm getting free charging, no dice.
1. Re:Screw that. by grmoc · 2013-12-12 05:33 · Score: 3, Insightful
  
  Yes, and if the batteries are a significant part of the price of the car (true today), this is potentially moving significant expense to the car's owner.
Electric cars are impressive power houses by ZorinLynx · 2013-12-12 05:22 · Score: 4, Informative

A Tesla Model S sitting in a garage has enough energy onboard to run a typical single family home for many days. It's pretty impressive just how much energy our automobiles use when we're driving them; they put the power consumption of homes and small buildings completely to shame.
1. Re:Electric cars are impressive power houses by Anonymous Coward · 2013-12-12 05:28 · Score: 5, Interesting
  
  Or to put it another way how little energy most things need. You don't need tons of power unless you're trying to heat somewhere or move heavy things.
2. Re:Electric cars are impressive power houses by TWX · 2013-12-12 05:30 · Score: 3, Interesting
  
  This is why I've considered putting a generator head on the PTO of a Dodge/Cummins truck. Damn near idling the truck would produce enough power to keep the whole house running during power outages.
  
  I've also considered building a battery room if I ever put solar on the house. Even running HVAC equipment it's doable.
  
  --
  Do not look into laser with remaining eye.
3. Re:Electric cars are impressive power houses by LoRdTAW · 2013-12-12 06:40 · Score: 5, Informative
  
  During Sandy we needed a temporary backup generator at work. We have multiple electron beam welding machines, electric heat treating oven, laser welding machines etc. Our building service is 1200A 120/208 three phase which works out to roughly 432kW. We pull about half of the panel rated load, or 600 amps on average and close to 800 peak. A towed 500kW CAT genset was hooked up and had a 15 liter engine, same as a the average semi truck. Ran the whole building without breaking a sweat. So a semi truck can run a small factory.
  1HP is roughly 746 electrical watts. the Nissan Leaf has a 110HP motor which uses ~80,000 watts at peak output. The average American home has a 100 or 200 amp 120/240 electrical service. 240V * 200A = 48,000 Watts, which isn't used constantly but with enough creature comforts, consumption can run pretty high (AC, electronics, lights, appliances, pool filters etc.). So when you put your foot down in the Leaf, you are pulling 2x - 3x+ more current than a household can provide. Gives you some perspective.
Check that title by Mr+D+from+63 · 2013-12-12 05:23 · Score: 3

Looks like 6 cars can offset about 2% of this office's power usage. Hardly 'powering' the whole office.
1. Re:Check that title by pla · 2013-12-12 05:32 · Score: 5, Informative
  
  Looks like 6 cars can offset about 2% of this office's power usage. Hardly 'powering' the whole office.
  
  You misunderstand - Businesses don't pay for electricity like residential users. They pay by usage per demand timeslot. So they may pay a rate of $0.05/KWH for 80% of the day, $0.12/KWH for another 18%, then for the remaining 2% (around 15 minutes) that shoots up to $0.45/KWH.
  
  This study found that you can run the entire building for those 15 peak demand minutes on six cars. Those 15 minutes amounts to way more than 2% of the business' electric bill (more like 10-15%), however, thus the huge net savings.
2. Re:Check that title by Mr+D+from+63 · 2013-12-12 05:43 · Score: 3, Insightful
  
  Also, remember these power rates in Japan are much higher than most other places, so the economics don't universally apply.
cut peak-hour electricity use by 2 percent by Saethan · 2013-12-12 05:24 · Score: 4, Informative

How many Nissan Leafs does it take to power an office building? The answer, it turns out, is six.

cut peak-hour electricity use by 2 percent
So the answer, it turns out, is actually 300.
Re:Billing? by Anonymous Coward · 2013-12-12 05:25 · Score: 5, Insightful

Also for the wear and tear on the batteries caused by the additional charge/discharge cycles. Batteries can only handle a limited number of cycles so this'll shorten their life. Those batteries aren't cheap either.
Why not just do this using batteries? by tftp · 2013-12-12 05:27 · Score: 3, Insightful

"Why not just do this using batteries--never mind the cars?"
Batteries have a limited number of recharge cycles, and they are very expensive (1/3 to 1/2 of the cost of the vehicle.) It's much easier to stick those expenses to the employees.
Other than that, yes, it would make a lot of sense to use stationary batteries. They wouldn't have to be light and small, for one. However it remains to be seen if the saved 2% is enough to pay for all the equipment.
Re:Externalizing the cost of maintenance by ottothecow · 2013-12-12 05:28 · Score: 3, Insightful

I would take the expense of maintaining my vehicle and getting to plug it in at work (with a guaranteed charge at end of day) any day over the prospect of having my car searched and being arrested for plugging it in to an available outlet.

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Bottles.
Super Capacitors by TrentTheThief · 2013-12-12 05:28 · Score: 3, Interesting

The idea to store all excess electricity is already being investigated. But they're planning to use super capacitors rather than batteries. The idea to buy it cheap at night and sell it back to the grid during the day when theoretically, your consumption is lower (not at home, etc.) is too good not to be exploited.
Company cars by TWX · 2013-12-12 05:32 · Score: 5, Insightful

I don't think it's intended for rank-and-file workers to supplement the company's electricity, it's probably more that higher-ranking employees with company cars would end up doing this.

If work gave me a car to use for several years, I don't think that the negligible electrical costs that I might incur at home would be enough to make me bat an eye at such an arrangement.

--
Do not look into laser with remaining eye.
Re:Already being done. by 140Mandak262Jamuna · 2013-12-12 07:23 · Score: 3, Interesting

Some of the habits of people are very hard to change, that much I agree with you. My uncle who immigrated in 1970. In his mind it is indelibly imprinted, "Coca Cola is cheap. Toilet paper is expensive". He would pay any price asked by a coke machine but bitch and moan about the price of toilet paper. But that is not always the case.
We know people waiting for 9pm to make long distance calls don't we? There were times we would yack on and on during weekends but be curt and to the point during week days before 9 PM. So yes peak load pricing would work. If you make it worthwhile. And what is not worthwhile to someone above 400% of FPL would be very much in demand by someone below 133% of FPL.
If one can make ice in the basement at nights and use it to cool the house in the summer day, 10$ a month savings would be worth it to someone, cutting the bill by half would be worth to someone else.

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