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New Scottish Wave Energy Generator Unveiled
MikeChino writes "We've learned about Scotland's wave energy initiatives in the past, and just this morning the nation unveiled Aquamarine Power's next-generation Oyster 800 wave power plant. The new generator can produce 250% more power at one third the cost of the first full-scale 315kw Oyster that was installed in Orkney in 2009. The device's shape has been modified and made wider to enable it to capture more wave energy, and a double seabed pile system allows for easier installation."
Well... every great plan has to have a doomsday scenario or two. This one is the worst yet.
As we know the tides are primarily caused by gravitational drag from the orbit of the moon. The moon has enough velocity that its orbit is actually widening, meaning the grip between the two bodies is getting ever so infinitesimally smaller. One generator stealing energy from this system is nothing, but once we start investing in it hardcore... the reduction in wave energy leads to extra gravitational drag on the moon, slowing its orbit... causing it to stop advancing, and be pulled in towards the earth.
By the time this is noticed, it is too early to convince politicians that something must be done now, and in fact, the push to convert more power over to wave energy.
How does it end? Well political infighting, and a new ad campaign by the deep ocean energy harvesters association begins extolling the virtues of the new larger moon, and begin funding both PR campaigns for surfing associations and contests.... and the new moon cult which has begun preaching that the moon is actually Jesus returning to earth. As part of their agreement with the energy harvesters, the cult members primary ritual consists of running Air conditioning all day long, with their windows open and bitcoin mining.
"I opened my eyes, and everything went dark again"
"A farm of just 20 Oyster 800 devices would generate sufficient power for up to 15,000 homes"
or... 1 device can power 750 homes.
No, all of the replies would have been put-downs, and they'd all have been written by Europeans, except for one or two from the US who would be whining about how someone, somewhere, might make eeeeevil money while doing this.
Don't disappoint your bird dog. Go to the range.
Capacity factors I found online for wave power put it at 30%-45% with a suggestion that 35% was a good average. That is, if the unit is rated at 800 kW peak, you can expect it to produce 280 kW averaged over the entire year.
Onshore wind farms have a 20%-25% capacity factor. Offshore wind seems to have a 30%-40% capacity factor, with turbines in the 1 - 4 MW range. So this wave power unit will on average generate slightly less energy than one of the smaller offshore wind turbines. In the KE = 0.5mv^2 equation, water has about 800x more mass than air, but the average wind speed is a lot higher than the average speed of the waveheight up and down. Enough so that it seems wind ends up having the advantage. (This is just a comparison, not a trade-off. You could for example install these wave power machines in between your offshore wind turbines.)
Comparing to conventional energy sources, the typical coal plant in the U.S. is about 340 MW with a 65% capacity factor, for about 220 MW average generation. So that's about 800 of these wave energy generators. The typical nuclear plant is about 1.55 GW with a 90% capacity factor, for about 1.4 GW average generation, or about 5000 of these wave energy generators. So we've still got a long way to go before these can truly replace conventional energy sources.
Unfortunately I can't find the price for one of these units, probably since they're still very much in the R&D phase. So I can't do a cost comparison. Also note that the Wikipedia entry for this project says it has three flaps each of which is capable of 800 kW. So depending on if the summary or wikipedia is right, the average power generated may be a factor of 3 higher.
If those numbers are correct for the original, and the summary is correct with its "250% more power at one third the cost", that would drop the new version to $11,000 / 3.5 / 3 = $1,047/kW, less than what you quote for coal (disregarding operating costs, which I have no idea of). Unless they mean the 250% extra works out to one-third the per-Watt cost, which would imply $11,000 / 3 = $3666, not bad but a bit pricey. Don't know which cost TFA refers to (old system or new one); anybody know?
Perhaps the pendulum should swing in the other direction? I laugh at the stereotypes of my ancestors (Polish and Irish top the list). Perhaps everyone needs to lighten up and laugh at the things that make us different instead of flying off the handle and getting offended.
TL;DR: lighten up, life's too short.
Women are like electronics: you don't know how damaged they are until you try to turn them on.
Roughly equivalent to a library of congress or a fotball field.
No it isn't. That's a small single generator of probably 1970s or earlier vintage, and you have several of them in a single power plant because you need a lot of cooling, water treatmentt, coal handling etc gear whether you have one unit or several. Many of the concrete cooling towers you see are designed to cool two seperate units for example.
If a power plant has for example four 650MW units that adds up to more than your number for nuclear, which is also wrong because there are some much bigger plants there along with the tiny research reactors and the many very small miltary run "power" plants in developing countries that bring the average down. Don't confuse "average" with typical and compare apples and orchards.
However, it's a myth that stainless steel is the best thing for salt water. It is fine for above-deck use because it gets washed clean by freshwater in rain. But the interesting ingredients of seawater can cause pinholing and stress corrosion in stainless steels, though A4/316 is better than most. Bronze (tin/copper alloy) is good and is traditionally used for throughhulls and seacocks. The usual solution (pun intended) is of course not to let seawater near any working fluid circuits but to use either hydraulic oils or a mixture of propylene glycol and water (anti-freeze) - use propylene rather than ethylene because it doesn't kill fish if it leaks out.
Corrosion engineering is a really fascinating discipline with many unexpecteds and gotchas.
From scarped cliff or quarried stone she cries "A thousand types are gone, I care for nothing, no not one."
As a Scotsman I'm offended at your derogatory and cliched view of my country. The energy is used to power deep-fat fryers, whisky distilleries and cigarette vending machings. Some energy is left over for TV sets in to watch our football team being crushed by all but the tiniest nations.
That's when we turn on the link to Shetland, where the wind never stops blowing!
The what?
We move to option number four, tidal, which is being trialled in the Sound of Islay. Tides are predictable - you know exactly when the energy will peak and trough, and can plan for it. In an ideal world we'd have tidal as our base generation, with the troughs supplemented by other forms of renewable energy buffered by pumped storage.