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Tesla Deploys Over 300 Powerwalls To Give Hawaiian School Kids AC (electrek.co)
Fred Lambert reports via Electrek: As part of a state initiative, Tesla deployed over 300 Powerwalls in schools to cool down hot classrooms in Hawaii. Hawaii has a problem with hot temperatures in public classrooms that is affecting students negatively. The problem was so significant that the Hawaii State Department of Education had to intervene. They put together a $100 million fund, which has already helped cool down 1,190 classrooms to date, with contracts set for more than 1,300 classrooms, according to The Garden Island. In order to roll out the program without significantly increasing energy costs for public schools, they partnered with Tesla to pair Powerwalls with solar power to reduce the impact of running the air conditioners in classrooms across the state. It also resulted in an interesting learning opportunity about renewable energy and energy storage for students.
well that only equals $40k per classroom :) Air conditioners + solar panels + batteries + labour
It's not a typo if you understood the meaning!
School happens primarily during the day. Heat is primarily a problem when the sun is shining brightest. The schools already have an electrical connection to the grid.
Explain again why they needed power-wall batteries for each installation instead of just using the solar power directly when it was needed the most (on hot, sunny days, which generate the most solar power) and relying on a little bit of to/from grid action at other times if necessary?
This sounds an awful lot like a publicity stunt, i.e. kids + batteries + renewable science, now everyone sing kumbaya!!!
The party of stupid and the party of evil get together and do something both stupid and evil, then call it bipartisan.
These Powerwalls just don't add up as truly economic solutions if you're a regular customer buying at Tesla's asking price.
Same problem Tesla has with those solar roof shingles. The estimated cost to cover the average size roof on a home makes them totally non-competitive with regular panels.
I really hope I'll see this change in my lifetime, and even better if it's fairly quickly. But battery technology really hasn't evolved at that fast of a pace. Much of the gains we've seen in how long you can go before needing to recharge a laptop or a phone have more to do with CPUs and other components increasing their efficiency.
Plus, the whole battery making process is REALLY environmentally dirty. The more batteries we use, the more negative environmental impact that production creates -- and right now, companies like Tesla are really trying NOT to address that issue. (It's nice to promise all the "feel good" things about batteries being able to be recycled over and over whenever they wear out, but many, many NEW batteries need to be manufactured to meet the needs for battery powered automobiles and power capture for PV solar. We're FAR from a point where all the batteries we'd ever need already exist can can just be re-used on demand!)
Heat lags peak solar by several hours. Hawaii's grid can't absorb the excess generated at nonn, and strains to supply the need as consumption ramps up just as solar is starting to fall. Some storage to time shift the produced solar power by a few hours is pretty much mandatory, once solar starts to be a large fraction of the total supply. You also need the storage to smooth out sudden dips likes a storm blowing in. Solar production can drop by 80% in a fraction of an hour. That's not a problem if solar is only a few percent of your energy mix, but it can lead to grid instability if the solar is meeting nearly 100% of the total demand at noon, and the conventional power plant is idling near zero output. Fossil fuel plants take time to ramp up. Battery storage (or other grid scale storage) is mandatory for a stable supply once solar (or solar and wind) become a large percentage of total supply.
The local net energy metering situation sucks
Bingo. This is the situation in Hawaii. Power retails for 42 cents/kwhr, about 4 times the highest mainland rate. Solar is currently about 10 cents/kwhr, and federal subsidies push that even lower. So Helco doesn't want to give up 42 cents to get something worth 10 cents. They no longer allow any new net metering installations.
This is, of course, stupid. But from Helco's point of view it makes sense, since they are in the business of maximizing profit from their monopoly market, not serving the public, and the PUC is bought and paid for.
So Hawaiians get one stupid policy ($100M Powerwalls for daytime use) to counteract another stupid policy (no net metering). This is what happens in a one-party state (there are no Republicans in Hawaii).
Hawaii also has zero geothermal energy, despite some of the best volcanic geology in the world, for equally stupid political and bureaucratic reasons.
geez if only Hawaii had some other more efficient and reliable sources of energy like Geo Thermal, shame they are in a region of the world with no such good alternatives,
School happens primarily during the day. Heat is primarily a problem when the sun is shining brightest. The schools already have an electrical connection to the grid.
Explain again why they needed power-wall batteries for each installation instead of just using the solar power directly when it was needed the most (on hot, sunny days, which generate the most solar power) and relying on a little bit of to/from grid action at other times if necessary?
This sounds an awful lot like a publicity stunt, i.e. kids + batteries + renewable science, now everyone sing kumbaya!!!
Silly questions but I'll try to answer it in a factual manner. On the Hawaiian archipelago they generate anywhere from 60-75% of their electrical energy (depending on which island you are on) with oil of all things. That and the fact that Hawaii is located in an area where solar panels should be quite efficient should result in there being a a good chance that the energy from the solar installation is considerably cheaper than the mains energy (In 2016, Hawaii actually had the highest electricity prices in the entire USA) so why not maximise the use of every spark of solar energy you can harvest even during periods of low sunlight? ... or should they be maximising the use of oil generated electricity and then sitting around a a big pile of extortionate electrical bills singing jolly songs in praise of the oil companies? If I was a Hawaiian I'd dimension my solar panel installation and battery pack in such a way that I'd never have to tap the grid for a single kilowatt all year round, the next thing I'd do after that would be to buy an electric car.
People don't realize that Hawaii doesn't just have one electric grid. It has one for each island with a low capacity level on each one. The issue now, and how valid depends on how much trust you put into the utility, is that there is so much solar currently connected there are serious issues of grid stability. It was built with generators with slow response times and now you have MW of power that flash on and off with a passing cloud. Someone had to put a surge system in, not sure the schools are the best ones though.