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Tesla To Announce Battery-Based Energy Storage For Homes
Okian Warrior writes: Billionaire Elon Musk will announce next week that Tesla will begin offering battery-based energy storage for residential and commercial customers. The batteries power up overnight when energy companies typically charge less for electricity, then are used during the day to power a home. In a pilot project, Tesla has already begun offering home batteries to SolarCity (SCTY) customers, a solar power company for which Musk serves as chairman. Currently 330 U.S. households are running on Tesla's batteries in California. The batteries start at about $13,000, though California's Pacific Gas and Electric Co. (PCG) offers customers a 50% rebate. The batteries are three-feet high by 2.5-feet wide, and need to be installed at least a foot and a half off the ground. They can be controlled with a Web app and a smartphone app.
This is one step closer to getting houses off the grid. And it's a pretty big step at that.
The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.
Let's be optimistic, and assume the battery lasts 10 years - 3000 cycles from full-empty.
This is perhaps optimistic.
I am using the numbers for my electricity costs.
These are $.28 or so.
If it's 10kWh, and lasts 3000 cycles, that's 30000kWh.
Or close on $10K worth of electricity stored.
Even with free electricity - it will never break even against grid cost.
Actually having to buy solar panels makes the numbers much worse.
Is it great for off-grid - perhaps. It's a _lot_ more expensive than even spendy lead-acid batteries.
Did you read the cost per battery? There is your answer right there. The summary talks about saving money by buying power during off peak hours and using the battery when power is expensive, but you'll never made $6,500 doing that before the battery wears out.
Apparently you have no clue what you are saying. Have you ever lived in California and payed by the tiered billing? I lived in the central valley and during a heat wave in the summer my elect bills averaged $750 a month with a high one month of $975. I heated with gas and so during the winter my electric bills were $150. So roughly I spend $600 - $800 a month for a/c. The Tier 1 rate currently is $0.359 peak $0.111 of peak a savings of 2/3 or $400 a month but I was Tier 5 which is $0.531 peak vs $0.283 off peak. The billing is complex but during the 4 or 5 months I used a/c I potenially might have saved $1200 a year. If the batteries last 6 years I come out a head but guess what if PG&E builds a new power plant to meet increased demand the rates go up.
The batteries are three-feet high by 2.5-feet wide
First 2D batteries ever! Advances in energy storage at a spooky distance made possible thanks to recently published ER = EPR discovery. Is Elon Musk really Ironman?
Donate free food here
Distributed storage capacity has the potential to even out the prices over the day and match consumption and production. It also solves a major issue with most renewables. It would be even more interesting if people were allowed to store cheap electricity and sell it back during expensive hours for profit.
true, and in a free market, that is exactly what would happen. sadly, the US energy market is no where near free. In the last three years, Koch Industries has successfully lobbied legislative bodies in 17 states to impede the deployment of alternative energy, and to drastically roll back, if not outrightly abandon existing programs. Case in point: net metering, where the utility company monitors power use and credits a homeowner for power sent back to the grid. In 2014, right here in sunny Az, three Koch-funded candidates were elected to our five person Corporation Commission, which, among other duties, sets utility rates. in february this year, they announced two structural changes that effectively kill net metering. the first change eliminates the ability to bank your credits over the length of a year, meaning that the credits needed to offset months where your PV array doesnt cover your power use are no longer available. the second change reduces the amount of money the utility will pay for your excess production, from full retail to less than half of wholesale. Arizona was seeing fairly strong growth in rooftop solar, until that announcement. in march, new residential solar permits were down 42% over Mar 2014. so far in april, there have been zero new residential permits.
They do that already with pumped-storage.
Pumped storage has an RTE (round-trip-efficiency) of about 80%. Modern li-ion batteries are over 90%. Pumped storage requires very specific geography (two reservoirs separated by a hill). Batteries will work anywhere.
There are also some liquid batteries.
The most common "flow" batteries are based on vanadium redox, and have an RTE of 65-75%.
Li-ion is just too expensive and maintenance-intensive to use grid scale.
Well, the point of this announcement is that Li-ion is getting cheaper. Li-ion grid storage still won't make sense in the middle of America, where power is cheap, and grids are wide. But it make make sense in places like Hawaii ($0.40 / kw-hr), where grid stability is already a problem.
The energy is not generated cheaply at night. It basically costs the same. (The idea when to charge batteries is a misconception on /. You charge during peak times, see below.)
That peak energy is expensive has not much to do with generation pries, but with grid logistics.
Consider you have a load following coal plant running at lets say 75% during a peak period, does not really matter, lets say a random time between 10:00 and 17:00 (5PM for the americans).
Now for some reason you get an extra load on the grid, which you can not fulfill, so you have to increase yield of the above plant. Unfortunately you can not adapt your plant to the exact demand, the coal plant can only change its yield in lets say 2.5% steps.
So after you have increased the yield you are producing to much energy. So actually you burn more coal than you need to fulfill the demand.
Either you have to sell the extra energy, store it in a pumped storage or let it go to waste in a resistor at the power plant.
Regardless what you chose: it costs the energy company. Hence they demand a premium price for peak times.
The closer the plants are running at the exact demand of the grid, the more likely it is they mainly create costs instead of revenue when they increase their yield. Or when demand suddenly drops!
That is where smart meters and batteries or EVs come in
During peak time, when energy is supposedly expensive, charging batteries will prevent that problem. Hence smart meter owners with storage capacity will mainly charge during peak times, and not off peak, for a special low price, not for an expensive price.
Of course you are not simply charging constantly during peak times. The power plants or the grid operators will remote control your charging, so they can "balance" the grid with your batteries instead of using pumped storage or wasting the energy.
Cost free eBook I read (by iBook/Kobo/Amazon/ObookO/Gutenberg etc.): "The Green Odyssey" by Philip Jose Farmer.
"Grid scale" simply can not be more expensive than single-house scale.
It is called "Economy of scale" and although some of such may have limits, beyond which cost of additional units begins to increase, none of the conditions for that would apply in this case.
In Soviet Washington the swamp drains you.
There are several problems with your statements:
1. " load following coal plant" No such thing AFAIK, they're all base-load. There are a few load-following nuke plants, but they're all in Europe. Load-following is done by combined-cycle gas plants and hydro while peaking is single-cycle gas and, rarely, diesel.
2. "That peak energy is expensive has not much to do with generation pries, but with grid logistics." Partially correct, but mostly not. Peak load requires peaking generators that are inherently inefficient--see "spinning reserve". Done properly, batteries could be used as spinning reserve and peaking instead of wasting gas turning a turbine that is delivering little power to the grid. Here's an example (using Na-S instead of Li): http://www.pgecurrents.com/2013/05/23/largest-battery-energy-storage-system-in-california-to-improve-electric-reliability-for-customers
3. "So after you have increased the yield you are producing to much energy. So actually you burn more coal than you need to fulfill the demand." Hence they are base-load, not load following, the maximize their efficiency. Ditto for nuclear plants (in most of the world). Since load-following is easiest with combined cycle (or single-cycle tied to a separate steam plant), they are used in modern systems. (The latter config (separate shafts and generators) can also be used for peaking.)
4. "... let it go to waste in a resistor at the power plant." Citation DEFINITELY NEEDED here!
5. "The closer the plants are running at the exact demand of the grid, the more likely it is they mainly create costs instead of revenue when they increase their yield. Or when demand suddenly drops!" This is so beyond wrong. The grid is at its most efficient when supply matches load, up to and just prior to firing up the inefficient peaking plants because the base-load and load-follower plants are maxxed out.
6. "Regardless what you chose: it costs the energy company. Hence they demand a premium price for peak times." You're right here, just not for the reasons you state above.
7. "That is where smart meters and batteries or EVs come in During peak time, when energy is supposedly expensive, charging batteries will prevent that problem. Hence smart meter owners with storage capacity will mainly charge during peak times, and not off peak, for a special low price, not for an expensive price." The is exactly 180 degrees opposite to what's really happening. The cheapest power is produced by base-load and hydro, then combined-cycle gas. Thus, charging during least-demand times and discharging during peak when demand is highest is what the power companies want. See the above link; also many power companies have special late-night rates for electric cars, such as here in Arizona. Guess when that rate is? Is it in the afternoon, like you say? Hell no! It's between 11pm (2300) to 5am (0500). Here's the one for APS: https://www.aps.com/library/rates/ET-EV.pdf