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World's First Lagoon Power Plants Unveiled In UK
AmiMoJo writes Plans to generate electricity from the world's first series of tidal lagoons have been unveiled in the UK. The six lagoons — four in Wales and one each in Somerset and Cumbria — will capture incoming and outgoing tides behind giant sea walls, and use the weight of the water to power turbines. The series of six lagoons could generate 8% of the UK's electricity for an investment of £12bn. Tidal Lagoon Power wants £168 per MWh hour for electricity in Swansea, reducing to £90-£95 per MWh for power from a second, more efficient lagoon in Cardiff. The £90 figure compares favorably with the £92.50 price for power from the planned Hinkley nuclear station, especially as the lagoon is designed to last 120 years — at a much lower risk than nuclear. Unlike power from the sun and wind, tidal power is predictable. Turbines capture energy from two incoming and two outgoing tides a day, and are expected to be active for an average of 14 hours a day. Friends of the Earth Cymru, said the group is broadly in favor of the Swansea lagoon.
While tides are predictable that are also predictably different than electricity demand curves. Storage is still needed to shift production to meet demand. Predictability is not dispatchability. Add the cost of storage need to shift production to demand and the cost is much higher.
While tides are predictable that are also predictably different than electricity demand curves. Storage is still needed to shift production to meet demand. Predictability is not dispatchability. Add the cost of storage need to shift production to demand and the cost is much higher.
Its not that simple. Tidal generation can also be used to temporarily reduce fossil fuel based generation. Throttle down the fossil fuel based plants during tidal generation, it predictable and schedule-able after all. Power generation can remain constant yet less fossil fuels are used.
No, it's not that horrible. England have about 16.000 miles (kilometers? I don't remember) of coast. The proposed generators will take about 30 miles. There will be plenty of coast left to all marine species. It's not a full perimeter siege, it's just a few barricades here and there.
Bonus points: it wont flood any place in land that is not actually flooded twice a day, it won't send more carbon into the air, will not release any radioactive isotopes, does not need a lot of rare metals, will not increase temperature.
So there'll be lots of hidden costs, like how 90 UKP per MWh is apparently the cheapest of the six things, if everything goes as planned. If not, well... budget overruns are not uncommon in large projects, are they? So with a lot of handwaving we might find that the price overall is really some thirty to forty percent higher than nuclear.
And with modern nuclear reactors, preferrably of the "fail-safe" type (As in doesn't need 'leccy to cool for days when you're trying to shut it off; while at it plan for something that doesn't leave 1%-used-up fuel that "needs" to be stored for 10k years. Yes, such designs are entirely possible.) the risks can be reduced quite a lot, too.
I'm really not sure which I prefer, but I do note that there's very little thought and quite a lot of agendas and ideology doing the rounds in this sort of "planning".
Nuclear is the safest power generation technology we've invented. Nearly an order of magnitude safer than solar, 2-4x safer than wind and hydro. If they're claiming to have come up with a technology which has "much lower risk," count me skeptical until they've proved it. Too often the people claiming such things look only at exotic outlier events like big accidents, while ignoring the more mundane events like maintenance accidents. The thing is, nuclear is so safe that per unit of energy generated, casualties from maintenance accidents from other power sources outnumber casualties from exotic nuclear accidents. And it's such a concentrated power source under such high scrutiny by regulators that nuclear maintenance accidents are also lower per unit of energy generated.
The USA has thousands of miles of coastline too. Alas, salmon were only interested in a tiny fraction of those thousands, and the dams built on that tiny fraction were a major problem for salmon.
So, what's going to be the problem fish/crustacean/whatever for these installations?
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