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Tesla Runs an Entire Island on Solar Power (engadget.com)
Jon Fingas, writing for Engadget:Now that Tesla has officially acquired SolarCity, it's not wasting any time showing what the combined entity can do. Tesla has revealed that it's running the island of Ta'u (in American Samoa) on a solar energy microgrid that, at 1.4 megawatts, can cover "nearly 100 percent" of electrical needs. It's not just the 5,328 solar panels that are key -- it's the 60 Tesla Powerpacks that offer 6 megawatt-hours of energy storage. While Ta'u is normally very sunny, the packs can keep it running for three days without sunlight. They don't have to worry about a cloudy day leading to blackouts. The solar switch, which took a year to complete, has both its long-term environmental and immediate practical benefits. Like many remote communities, Ta'u previously had to run on diesel generators. That burns 300 gallons of fuel per day, which is neither eco-friendly nor cheap. Solar eliminates the pollution, of course, but it also saves the cost of having to continuously buy and ship barrels of diesel. And crucially, it provides a more reliable source of electricity.
As indicated, shipping fossil fuel has high costs, and operation is noisy. Sunlight works even on cloudy days, and you can run desalination plants using solar, and it withstands weather effects fairly well.
Many islands operate with a hybrid solar and wind system, especially in equatorial regions.
-- Tigger warning: This post may contain tiggers! --
While the idea of a sunny Pacific island may seem like an easy and ideal place for solar power, this may not be the case.
When I worked for NOAA, I heard wild stories about how the molds in Samoa would destroy our scientific instruments. They would even eat glass... This should prove an interesting and challenging situation.
Don't forget the shipping cost of those 300 gallons of diesel per day, the maintenance and parts required for the generators, etc.
At $2.50 a gallon (seems to be current US price?), 300 gallons a day costs $750.
Which means that THE BATTERY for that system that runs for 3 days only without solar would cost the equivalent of 10 years of diesel.
Sure, there's a lot of losses, shipping, conversion, other equipment on the diesel side, but there's also a lot of solar etc. required on the Tesla side that's unaccounted for above. And it would take 10 years to break even just on the battery storage alone, let alone the solar + battery.
Sure, it's not linked to oil prices, but it's still only just verging on "viable" assuming nothing ever goes wrong. Same as every "green" project I've ever done the numbers for.
You're thinking of the US cost. That's going to be a lot different on an island like this in the middle of the Pacific Ocean. Take that $2.50 per gallon, and multiply it by the cost of shipping to Samoa. At an offhand guess, you're talking anywhere from 5 to 10 times as expensive.
This is the perfect proof of concept that Musk is aligning all the pieces needed for Mars Base 1.
SolarCity for the energy collection
Tesla for the storage and local transportation
SpaceX for the "long haul" to/from Mars, as an umbrella for the expedition and for the environmental pieces (habitat design, space suits).
This space for rent. All reasonable inquiries will be entertained at proprietors discretion.
Li-ion voltage degradation curves generally don't plunge off a cliff, the rate of degradation slows down significantly with time. For a lot of consumer goods this isn't of much use because the voltage drops below the threshold and it becomes usable. But if the Powerwalls have a good voltage conversion then they might be able to get quite a long lifespan out of them.
Still surprised at 10% loss of capacity in 10 years. I'd have thought that they'd have a low DoD and climate control paired with low discharge rates to prevent that. Now I'm wondering about their architecture. I imagine it's similar to how the Tesla packs work, where you have many cells in parallel comprising bricks (so a single-cell failure causes only a minor increased load on its neighbors), bricks in series to form sheets, and sheets in series to form the pack.
Wingus, Dingus! Listen up!
Betting on the price of replacement batteries going down is probably as safe or a safer bet than betting on the price of fossil fuel to remain stable over an entire decade.
Someone had to do it.
Diesel cost in Samoa as of last July (quick Google check) was $2.06 to $2.28 per liter. That's between $7.80 and $8.63 per gallon. Call it $8.00. 300 gallons per day, 365 days per year, gives an annual cost of roughly $876,000. A $2.75 million battery cost would be paid for in saved fuel costs in a little over 3 years.
Still have to figure in the solar panel costs. It's a 1.4 MW microgrid. Current Google response on solar panel costs is $3.57 per watt. There's federal compensation for solar installations (~30%), but I have no idea whether they'd be able to get any funding/credit for that, given that it's not a home installation. So going with the $3.57 value, 1.4 million watts would cost $4,998,000.
Total cost is thus $7.75 million. Figure maintenance costs balance out with the diesel setup (less to break, more expensive per break), so no real effect there.
Total buyback cost in terms of diesel fuel would thus be slightly under 9 years, not counting inflation or continued increases in fuel prices. Allowing for cost fluctuations, you could then say that the entire solar grid plus batteries should for itself within 10 years, which is a pretty decent rate. As long as the replacement time is significantly above that, it's a good deal.
That part of the world has very reliable trade winds. One wind turbine could generate several times as much power and would probably cost much less.
Diesel usually cannot be stored for longer than one or two years:
Diesel bug is a thing.
That's actually another reason for regular generator tests in backup facilities:
It frees up storage volume that can be filled with fresher fuel.
He has altered the deal. Pray he does not alter it further.
The world's burning. Moped Jesus spotted on I50. Details at 11.
Longer than the barrels of diesel fuel anyways.
All of which, added up, is no more than a small fraction of the environmental cost of pumping, transporting, refining, flying in and then burning all that diesel.
If there is an award for the comment that best embodies the slack-jawed, drooling idiocy of the neo-conservative right, surely it should be won by the one above.
I've calculated my velocity with such exquisite precision that I have no idea where I am.
Well, given the solar array is 1.4Mw and the 6M of batteries have "3 days" emergency runtime, their usual daily depth of discharge is likely to be well under 40%.
Someone had to do it.
> Solar eliminates the pollution, of course
Except for the pollution from mining the rare earth metals, and the whole solar manufacturing process.
What "rare earth" metals would that be? Solar cells are silicon
Pain is merely failure leaving the body
Solar panels can be had for closer to 50 cents per watt these days. The cost you found is average installed cost on a house roof. The cost should be substantially less for a grid scale installation.
Orkney, a group of islands of the north coast of the UK is apparently now self sufficient in electricity from wind turbines. Yes we still have a diesel fired power station in case of problems and an undersea link to the UK national grid.
This is the future - solar, wind, whatever, not filthy fossil power pushed by some bad tempered businessman with dodgy hair.
I'll see your Constitution and raise you a Queen.
It's a small island community, building a deep water port and the associated fuel storage/distribution infrastructure just so you can "buy in bulk" is economic insanity.
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
Keep in mind, also, that you need a harbor that can support a 20,000 DWT tanker.
https://www.google.com/maps/pl...
It's an island near the far tip of the island chain extending north-east from Australia, roughly midway between New Zealand and Hawai'i, about 2000 miles from either, and over 60 miles from the bulk of American Samoa, with no obvious intervening islands aside from it's nearby sister island . Looks to be about as close to living in the middle of the open ocean as you can get, and as such I'm guessing ferries aren't the preferred method of transportation, especially carrying when transporting toxic and explosive payloads.
That remoteness would no doubt serve to make solar *extremely* attractive.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
It'd be a real shame if Ta'u can't keep up the payments to Solar City and their power controllers all stopped working at the same time.
As opposed to the regular diesel shipments, which would definitely continue to arrive whether any payments were made or not?
I don't care if it's 90,000 hectares. That lake was not my doing.
The going rate for uninstalled solar panels is about $2/peak watt.
Where? When? That's a little bit too much for the hardware. Also, you seem to be counting with all power going through the batteries. That probably unrealistic; a significant portion will be directly consumed.
Ezekiel 23:20
1) none of those are rare earth metals, and even if they were, 2) none of those are required for PV technology anyway.
Ezekiel 23:20
The Radio NZ article says the cost of the project was US$ 8 million.
I don't read your sig. Why are you reading mine?
Always reassuring to know that the back of the envelope got pretty close.
My kingdom for some mod points!
So the back up for solar is properly managed sewerage, as in a methane farm and you store that methane, compressed (using solar power), to power gas turbine generators when needed and produce hot water, for direct local use (care needs to be taken where the plant is to be located).
Chaos - everything, everywhere, everywhen
So years 11+ are free? Where do I buy one?
Call Solar City, tell them I sent you, we both get a free month and I get $100
Only I can judge you.
The link I posted says "and comes with an integrated inverter". This is what they call "AC Coupled", rather than "DC Coupled". In other words, this is designed for a system that adds batteries to a grid-based system. AC current is generated either at the panels (via microinverters) or using a string inverter that connects the panels to directly to the grid. The "battery" is an add-on that consists of cells, plus a charger and an inverter. When viewed as a black box, the "battery" is AC.
In traditional DC Coupled systems, DC is sent from the solar panels to a (DC) battery bank. Then on the other side, an inverter connects the battery bank to the AC circuits or grid.