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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.
Hawaii has a problem with hot temperatures in public classrooms that is affecting students negatively.
For sure? Have studies been done? Is Hawaii hot? Wow, new info for me!
But seriously, this is the kind of stuff that will keep giving back to Tesla, they may be "giving away" a lot of stuff, but they are actually building the network that will be the foundation for the future and they are getting their foot in the door before GE or some other huge infrastructure company gets a foothold on the technology.
If you want news from today, you have to come back tomorrow.
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 is primarily a problem when the sun is shining brightest.
It's Hawaii, man. It's hot all day. Additionally, buildings function as heat sinks.
School is about seven hours, Hawaii gets 14.5 hrs of near-equatorial sun in June. That's 7.5 hrs of storage, assuming the AC is set back outside of school hours.
Also, power is crazy-expensive in Hawaii which is one of the reasons so many people there do solar.
My God, it's Full of Source!
OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
+1 for that AC. The power stays on for the community when needed.
Domestic spying is now "Benign Information Gathering"
thats thai pricing, roughtly. enough for a room.
1000 gets you an office space/bigroom luxus model.
basically those school systems pay off themselves in 30 years. I really have to think that tesla is starved for buyers for the powerwall. which is a stupid fucking name anyways. Tesla powerBANK would be a better one, since it would lead to less disappointment about what it actually is.
world was created 5 seconds before this post as it is.
With some rather generous assumptions -- a 42,000 BTU, 5.3KW unit costing $10,000 (installed) in each classroom, 180 days of school per year with the unit operating at full power for 10 hours a day -- I get break even in 9 years assuming no additional expenses. This isn't terrible but I suspect with more realistic assumptions break even would take much longer.
In other words, there's plenty of solar energy available exactly when it's needed to cool the class rooms.
So, as GP asked, what's the point of the batteries?
They don't have maths classes in Hawaii. They only teach one math.
sorry forgot they don't teach English in the US.
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.
There's only 2 reasons for a powerwall:
The grid is unreliable/too remote
The local net energy metering situation sucks
Consider, fuel for generators comes from the mainland. Grid electricity is expensive in Hawaii.
Meanwhile, solar is highly effective in Hawaii.
Not since we threw them all out.
Insulation in Hawaii is generally crap. And forget true basements; what Hawaiians calls a basement is just the lower level of a house built on a slope.
14.5 hours of solar during 7.5 hours of school, hard to do without the batteries.
Easier (and cheaper) to do it without the batteries. Just feed excess power into the grid, and draw out to cover peak demand.
I can't see how batteries make any sense at all for this application. The only plausible explanation is that it is all a stupid PR stunt funded by the taxpayers.
Consider, fuel for generators comes from the mainland. Grid electricity is expensive in Hawaii.
Meanwhile, solar is highly effective in Hawaii.
I'm sure the coal lobby is desperate to start doing investigative mining.
If they're not successful, they'l be more than happy to ship coal from the mainland... /s
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.
Hawaii isn't on the Ring of Fire. It has volcanoes, and the earthquakes that come with them, but it is in the middle of the Pacific. The Ring of Fire follows plate boundaries around the outside of the Pacific - from Chile up the coast of South and North America to Alaska, around to Japan, and down to New Zealand through Micronesia and Melanesia, with a branch off through the Philippines and around to Indonesia. Hawaii is one of those isolated spots of activity mid plate that pop up in a few places (Iceland is another).
yep typical politicians piling one poorly thought out policy on top of another, with Tesla their to cash in on the bad decisions. Not that I blame Tesla for that, if government is stupid enough to give away money you may as well put your hand out.
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,
Why would you care? Unless you've had a lot to say about fossil fuel subsidies totalling $5.3 trillion (more than 6% of the entire planet's GDP), you should probably just relax about a few bucks going to solar power, especially when it keeps getting cheaper and cheaper to install and use.
https://en.wikipedia.org/wiki/Energy_subsidies
I've calculated my velocity with such exquisite precision that I have no idea where I am.
They do not get that their work is absolutely critical for the future of a nation. Or rather those that decide the budget and staffing of education departments do not get that and place 2nd and 3rd rate people there and give them too little budget to do the job well in addition. The underlying problem is that politicians cannot see or plan beyond the next election and bad education has an effect that is delayed by 10 years or so and then only ramps up over time. That bad education continues to have a negative effect for something like 50 years and longer if you add indirect effects (teachers being taught badly as children usually teach badly themselves...) is completely beyond the comprehension of political "leaders".
Most ACs are not even worth the keystrokes to insult them. Be generically insulted by this and ignored otherwise.
TFA isn't clear, but a lot of the state doesn't really have a grid. It would be good to know how many of those walls will wind up in places like Kauai, where they still provide power to buildings by running diesel generators.
I've calculated my velocity with such exquisite precision that I have no idea where I am.
Did you really ask why do solar panels need batteries? It's almost like the power they generate isn't smooth and they needed something to help with that.
You know, I hear capacitors help smooth out energy curves. Maybe a big capacitor? Oh! Like a....
Battery.
You must have dropped out in 8th grade. I had to take at least 6 of them.
Sounds about right. I'm also betting nobody bothered to explore low tech solutions like shade and reflective paint. Where I live it's as hot as Hawaii and schools get by without AC.
A source for this claim about Singaporean classroom temperatures? Because it would be very unlike the Singaporean government to not put AC in classrooms.
+ HIDOE’s heat abatement efforts also consist of installing ceiling fans, using nighttime ventilation, painting roofs with heat-reflective coating and extending shade + Solar-powered weather stations mounted on these schools transmit data to a receiver in the school office, which is then posted to the new HIDOE Thermal Comfort website. Indoor classroom temperatures are monitored by the use of 737 data loggers that record the temperature and humidity every 30 minutes
If only there were articles describing the other efforts being funded by the $100m. Like "HIDOE’s heat abatement efforts also consist of installing ceiling fans, using nighttime ventilation, painting roofs with heat-reflective coating and extending shade."
How come a country as highly developed and as rich as the USA doesn't even have A/C in schools in what is possibly one of the hottest parts of the country?
And, as others pointed out, an electricity network that is not even able to provide the power for those A/C units?
At maybe 10 kW per classroom (with halfway decent isolation that should be more than enough to cool it down) that's a mere 25 MW of electricity - spread out over the network.
School happens primarily during the day.
Yeah, and it's not like the school cafeterias need refrigeration to store food.
relying on a little bit of to/from grid action at other times if necessary?
Because electricity from the grid in Hawaii is devilishly-expensive, over USD $0.40/kWh, and much of it comes from burning diesel fuel that must be imported by huge tanker ships that burn even more fossil-fuels. More than likely it's also designed so that extra electricity generated will be sold back into the grid and offset costs while reducing pollution and fossil-fuel use even further.
It's like the Left hates Musk because Musk is doing all the cool things they thought a huge nanny-state government would do for them while adding insult to injury by doing it better and cheaper than the government could. Nannies don't do cool stuff, they just nanny.
and the earthquakes that come with them
As those are shield volcanoes, the region should be fairly stable, seismically...
If you did, u would see that a lot more is going on than just adding AC.
I prefer the "u" in honour as it seems to be missing these days.
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.
Part of the issue there is build-up of heat over the day, causing that lag. With better sun screens, building design, insulation, and thermal mass, buildings can work well with solar generation in summer and winter, although not all of those options are going to be cost effective to retrofit for all buildings.
Sorry Mary Poppins would disagree :-)
School happens primarily during the day. Heat is primarily a problem when the sun is shining brightest.
Well, there's your problem right there. Just implement a daylight savings time extreme in Hawaii, shifting the clocks by 12 hours.
Send the little bastards to school at night!
Schroedinger's Brexit: The UK is both in and out of the EU at the same time!
Iceland is not a good example as it is right on the mid-oceanic ridge where the Atlantic is spreading at the juncture of two plates moving away from each other.
A better mid continental hotspot example would be Yellowstone.
I'm too lazy to compose a creative sig.
Please cite news reports of teachers dying due to insufficient pay. Teacher pay isn't great but even in the worst state it's well above the poverty line, even for first year teachers.
It seems the plate map I looked at before posting was too low resolution - it looked like the plate boundary was almost as far east as UK/Ireland, and I was looking at the little red spot (indicating activity) to the NW a little bit inside the North American plate thinking that must be Iceland.
Trump recommended Hawaii install all the Powerwalls in a row to make an actual wall, to keep out the Mexicans.
It must have been something you assimilated. . . .
No, they've done 1190 and have contracts for another 1300. This is 2490 classrooms total.
The article is not clear on whether the $100m fund is for all of these classrooms, the initial buy, or a larger project of which this is only one phase.
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
Electricity is relatively expensive in Hawaii. If they are buying panels anyway to offset AC consumption, it could easily make economic sense to buy batteries. The batteries allow them to continue using those panels even when the kids aren't in class.
And I don't buy the argument that they could just feed the excess power into the grid. Where I live, the utility company pays jack compared to what they charge. I double the value of my generation if I store/use instead of sell/buy. This makes batteries a very good economic decision---in my area, at least.
In Hawaii, it looks like there is a feed-in tariff. So going with batteries, you eliminate that right off the bat. I couldn't find published rates, but if Hawaiian Electric works like my utility, those batteries will pay for themselves well before their expiration.
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According to the latest ruleset, this post should be modded as Vorpal Flamebait +5.
Utilities in Hawaii are not very grid-tie friendly
The left always like to thing along the lines of "How can we best make do with what resources we already have and redistribute them fairly?"
So they would prefer to remain stuck with high electricity prices and have taxation on the wealthy to pay the high electricity bills of the poor.
When someone comes along with the ability to bring down energy prices to close to zero, suddenly their whole economic model pops like a bubble and the left have no purpose.
I doubt it has anything to do with democrats versus republicans.
It simply is the idea of americans that money rules the world.
Regarding geothermal power, it is not so easy to use geothermal power to create electricity. Not hot enough. And on Hawaii you don't need it for heating. So I doubt there are any "political" reasons against geothermal power.
Cost free eBook I read (by iBook/Kobo/Amazon/ObookO/Gutenberg etc.): "The Green Odyssey" by Philip Jose Farmer.
$100m toward utility level solar PV and some storage, minus $5M or so to put mini-splits in classrooms, would yield much more bang for the buck, but its a political win when you can talk Tesla AND schools, the masses have no clue.
Sorry Mary Poppins would disagree :-)
Well naturally, That evil Poppins woman created the Umbrella Corp and doomed Racoon City. after all.
Strat
Progressivism (aka US 'Liberalism'): Ideas so good they need a police/surveillance-state to enforce.
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.
Nat Gas and even hydro generation can ramp fast enough to deal with wind variability, it is more challenging for solar in a small area where you can have those massive swings but it doesn't have to be 100% battery backup.
Yeah! By God, when I was their age, I had to walk to school! In the snow! Up hill! Both Ways!
Sweating builds character.
Now get the hell off my lawn!
I went to high school in Hawaii, and I don't understand how this could work without rebuilding the high schools themselves. Most (if not all) the schools are open-air campuses; there's no indoors except the classrooms themselves. The classrooms have no significant insulation (why would they?), and generally feature jalousie windows. How they intend to keep the cold air in is a mystery to me. The other thing to consider here is that it's not just the heat that's the problem. The "heat" itself is generally just fine, it's not like Las Vegas or Phoenix out there. It's the humidity that gets you, and you get acclimated to that after a few months. I'm sure I'm missing something but when I hear A/C in Hawaii schools I immediately imagine all that cold air seeping out the jalousies and the A/C units constantly overworking. Sounds like a massive waste.
Since most of the population and industry are on O'ahu, with the other islands being largely rural and agricultural, it seems to be a good test case. If it works, then see if it can scale down to the smaller islands where the benefits would presumably be lower and the challenges greater.
Nonaggression works!
The challenge then would be getting it to O'ahu where most of it is needed. That's at least 300km total. Presuming you could run cable on land or underground on Moloka'i and Maui, you'd still need at least 60km of cable to get from Maui to the Big Island. Maybe more. I have no idea what that would cost. I'm guessing more than a little. We're not talking about a data signal, but actual power, and lots of it.
Nonaggression works!
If native Hawaiians are freaking out over a telescope being built on a "holy mountain", what exactly do you think their reaction to tapping that holy source of heat would be?
https://en.wikipedia.org/wiki/Opposition_to_the_Mauna_Kea_Observatories
The $100M will be used for a number of things. In addition to air conditioners and grid infrastructure improvements, the HIDOE’s heat abatement efforts also consist of installing ceiling fans, using nighttime ventilation, painting roofs with heat-reflective coating and extending shade.
You think it's the only Hawaiian island?
I've calculated my velocity with such exquisite precision that I have no idea where I am.
How much natural gas and hydro power does Oahu have? We're talking about a special case here, not like anything on the mainland.
"When you have eliminated the unacceptable, whatever is left, however improbable, must be the truthiness" - Holmes
Do we leftists hate Musk? I must have missed the last Masters of Socialism meeting.
"When you have eliminated the unacceptable, whatever is left, however improbable, must be the truthiness" - Holmes
From the Midwest here. High humidity and 70f can feel down right hot. I have trouble sleeping when it's 60f and 100% humidity. Get all sweaty and sticky. It's like you feel cold and hot at the same time. Horrible.
From what I've read, the batteries are expected to maintain 100% of their rated power for 10 years, assuming a full rated battery cycle every day. You could replace the battery after 10 years, but it should at least still hold 80% charge and expected to be at 100% and down to 80% after 20 years.
So, power would be free for everyone during the day, and exhorbitantly expensive at night, or in a monsoon? The powerwalls help balance the grid load, which makes it a net positive for the school, and everyone else in the communities.