Top-heavy marine device falls over, film at 11

[fivemack]

http://www.tridentenergy.co.uk/index.php

I don't quite understand how what these people are trying to do makes any kind of sense at all; their Web site looks like the write-up of a good A-level design technology project, and says in pieces dated February that they're about to start the test that clearly just failed to start in mid-September. The design seems to have a single guidance bearing taking all the sideways force of North Sea waves, held up on a remarkably flimsy-looking tower, and their prototype is made of eighty tons of steel and using four quite complicated linear generators to generate twenty measly kilowatts. I admit that I was slightly surprised that any marine engineers were involved in the endeavour at all.

What have I missed?

I'm sure it's unfair to compare the cost of tidal equipment to that of wind or solar; there's been, what, three orders of magnitude more money available for optimising wind and solar. But I can't help feeling there's a conclusion to draw from the fact that almost every story I read about wave power involves a wave-power demonstration, set up by a small company and producing less power than the smallest wind turbine Vestas will deign to sell, being destroyed by the wrath of Poseidon.

Comments

[arnhem.livejournal.com]

Surely the big problem with tidal energy harvesting is getting the power back to where you want to use it? [ similarly, to a lesser extent, with covering deserts with solar panels ].

On the other hand, if you've got an energy-intensive way of fixing atmospheric CO2, it doesn't really matter where you do it ...

[fivemack.livejournal.com]

If you're doing it with things moored to the sea bed, then almost-surely you're in shallow water, and shallow water tends to be close enough to land that running the cables isn't a serious problem; running an 80cm pipe 300km into Teesside was done in 1975. For the big estuary barrages you can just run cable along the barrage. I don't think getting the power back is a show-stopping problem with wind farms on Dogger Bank.

Desert solar power is harder for Britain simply because the nearest deserts to us are distinctly far away, and either the water's deep and swirly (I imagine sticking a gigawatt cable across the straits of Gibraltar would not be straightforward) or you have to go by way of Jordan, Syria and Turkey.

I assume you fix CO2 where you can store the fixed CO2, and either build fission plants on-site or run long cables ... the amount we'd want to remove from the atmosphere is on the order of a trillion tons (same order of magnitude as total coal ever mined, unsurprisingly), so figuring out where to put it is I think the harder problem.

[htfb.livejournal.com]

It's not the length or depth of the wire or pipe---transatlantic cables were laid in the nineteenth century. It's the capacitance between the wire and the seawater.

[fivemack.livejournal.com]

Last week National Grid started laying the 260km BritNed cable from the Isle of Grain to Rotterdam to carry a gigawatt to the Netherlands (cost €600 million); there's been a 2GW cable to France, eight parallel underwater cables of 46km each, since 1985.

National Grid are talking (http://www.publications.parliament.uk/pa/cm200809/cmselect/cmenergy/memo/futurenet/ucm02002.htm) about connecting up 32GW of wind turbines using cabling which will cost them up to five billion pounds (the wholesale price of 32GW * nine weeks, so even with a pessimistic load factor less than the price of the electricity the turbines would produce in a year) over the next fifteen years.

[htfb.livejournal.com]

BritNed and the link to France are HVDC (high voltage direct current) links, which is the technical solution to the capacitance problem. Other HVDC projects proposed will link Europe and Africa (http://en.wikipedia.org/wiki/List_of_HVDC_projects). It's not an insuperable difficulty, in other words.

[fivemack.livejournal.com]

We seem to be agreeing furiously with one another that the cables are a well-understood problem - might be expensive, but will be available.

Will continue debating the merits of venture capitalism in the other thread.

[htfb.livejournal.com]

True. We should put our thoughts about power-transfer cables, which while an ecologically sound concept are a bit bland, to rest. But I'm loath to let so much fury just evaporate: can't these colourless green ideas sleep furiously?

the nearest deserts to us are distinctly far away

[ewx.livejournal.com]

Perhaps instead of moving the energy from the deserts to the population, we should move the people to the energy-generating deserts? We could repurpose the land occupied by cities in fertile countries to growing food. A modest proposal l-)

[jiggery-pokery.livejournal.com]

running an 80cm pipe 300km into Teesside was done in 1975

I work in the same office as the people who deal commercially with a non-trivial proportion of the gas that flows in through said pipe. From potentially inaccurate memory, I think the pipeline is a little bigger than you suggest. Not an order of magnitude, but bigger all the same. I suppose this makes the technical achievement marginally bigger still.

Desert solar power: my issue with that is that of transmission losses, which are non-trivial already even within the UK, hence why people sometimes talk about local generation and being off the grid. Are there order-of-magnitude improvements to be made in minimising transmission losses through using better conductors, or do better conductors require cooling to an extent which is impractical?

Unrelatedly, do you have any bright ideas where would you look for a price assessment for UK power in 2013? (Say calendar year 2013, baseload.) All the obvious sources I can think of are either non-trivially non-free or stop in 2012. Part of the reason why nobody wants to quote, I would guess, is that nobody specifically knows what the EU ETS environment in Phase III is going to be like, though we can guess. Nord Pool quotes a price for 2013 vintage EUAs but people don't trade in the market in practice.