New renewable idea

[tim...]

I've got my popcorn ready

tim

[alan_m]

And just after it is completed, and the world is reliant on it, we have a once in a thousand year storm event which wipes it all out.

[quote] "A giant wind farm in the North Atlantic would have to operate in ?remote and harsh conditions? with wave heights frequently exceeding three metres (9.8ft)" [/quote]

A quick Google suggests that the writers of this article have underestimated the wave height by at least x10 for storms or for recorded freak/rouge waves.

[tabbypurr]

quote...

Derek Colman

I have a better idea. If we attach billions of hamster wheels to tiny gener ators over an area the size of Africa, they could power the entire world. T hey would have the great advantage of not needing scarce rare earth mineral s. They would be more sustainable because they can be made of wood which is renewable. The only disadvantage I can see is that I might end up in the s ame lunatic asylum as the guys who thought this one up.

[Bill Wright]

"10 photographs to show to anyone who doesn't believe in climate change" They don't show anything that proves anthropomorphic climate change. Total greeny nonsense.

Bill

[Chris Hogg]

+1 Even a few miles off Land's End, at the Sevenstones Light Vessel, they regularly get 'significant wave heights' of 10 metres in the winter, and that's only the average of the highest 33% of waves. A good number of them will be considerably higher than that.

[Chris Green]

Are those rouge waves ones that come from Russia?

[PeterC]

I red that as...!

[Chris Hogg]

Perhaps they'll resurrect ocean thermal energy conversion next, yet another green white elephant (OK OK, it'll be stripy elephant!).

Some interesting old photos from a 1930's pilot plant on here if you scroll down

[Nightjar]

Satellite measurements show that waves in the range 20-30m are not uncommon in open waters.

[Brian Gaff]

I'm just wondering why nobody has used the column of water and pumping something with its rise and fall type of power generation. It would not matter what direction the pressure waves came from but would need a very big column in a hostile see to make it viable. Brian

[Harry Bloomfield]

Brian Gaff presented the following explanation :

I suspect the constant and rapid reversal of the flow would make the system very inefficient - just too rapid for the mechanicals to respond.

[Bob Eager]

I thought you only got those in the Red Sea.

[Chris Hogg]

Wave periods are in the range 5 - 7 seconds, so unlikely to be too fast for the mechanicals, depending on what they are of course. Even the massive Cornish beam pumping engines of the 19th century had those sorts of cycle times.

There's quite a lot of experimental and pilot-scale work going on to harness wave power by floats bobbing up and down, driving pumps or generators. See

, , ,

The wave hub was installed seven years ago almost exactly (September

2010), at taxpayers expense, and so far nothing has been connected to it and not an amp of electricity has come ashore. The only thing that impresses me about the wave hub is how their publicity people manage to keep putting out optimistic press-releases and keep it all in the public eye, in spite of it all being smoke and mirrors. A friend of mine was shocked recently to hear that nothing had been connected to it since it was installed: he'd been completely taken in by the propaganda they put out.

One of the major problems that any wave energy device will have to overcome, will be being robust enough to withstand the extreme conditions of winter storms.

[The Natural Philosopher]

All renewable energy is chasing two issues, both of which are routinely ignored

The first is related to energy density, and it is how big and costly a structure you need to generate the power.

The second is the intermittency, how steady the power source is. Note that *predictability* is no help. Knowing that 100GW of UK solar energy will go offline at 8pm in summer doesnt mean you still dont have to deal with it.

To get some idea of how it all works: Take an offshore windfarm of plate capacity 2GW.

Its cost will be around the £6bn mark. With a life span of 20 years probably. In order to deliver 2GW reliably to the consumer, it needs a

2GW cable connecting it to the grid (About another £0.5bn, cost borne by te taxpayer via Natonal Grid charges in your bill) plus the cost of a 2GW gas power station whose output will be varied to ensure the combination always delivers a reliable 2GW 24x7 even when the wind doesn't blow - cost about £1.2bn

At a capacity factor of 30%, the addition of windmills to the gas power staion represents a saving of around 15% in fuel costs (the gas power station part load inefficiences and start stop losses will reduce the theoretcical 30% to about half according to am Irish study).

So given that the windfarm would need to be replaced *three times* over the 60 year service life of the gas power station we have

WITH WINDFARM ADDED - CCGT ALONE NUCLEAR ALONE Capital costs* £19.7 bn £1.2 bn £19.7 bn Fuel costs** £35.7 bn £42.0 bn £ 3.9 bn O & M costs*** £0.97bn £0.06bn £ 0.97bn Total costs £56.3 bn £43.26bn £24.57bn

So over 60 years adding a wind farm will knock £6.3bn off the gas bill, at an extra capital and O & M cost of £20.67bn

Now if we add in cost of capital, assuming it isn't an interest free loan from a subsidised Green Bank...

At 7.5% p.a. £0.727 bn £0.09bn £1.4475bn

So total cost £54 bn £43.35bn £26.0475 bn****

How much does this add to the fuel bill?

Over 60 years per unit cost 5.32p 4.27p 2.56p

Now if we look at the difference in price, that is 1.05p

But in that scenario wind only generates 30% of the total so the added cost of the windpower - the TRUE cost of wind power - is 3.5p over and above the gas price.

(WIND * 0.3 + GAS * 0.7 = 5.32) ( GAS = 4.27 )

So we can see that gas per unit wholesale is 4.27p, whereas te opportunity cost of wind per unit is overall costing us 7.77p wholesale.

Nearly double.

Note that the cheaper gas is, the more expensive in comparison wind is. And nuclear of course. Cheap gas and high interest rates are what stopped nuclear in the 1980s

Note also, that rather a lot of the costs are borne by the consumer, and the gas operator but *not by the windfarm operator*.

Note how cheap nuclear actually is. If you exclude insurance and political uncertainty even at a ruinous price of £9bn per GW build + teardown price.

I will leave the reader to work out how much carbon emissions were reduced for all this added cost. And how much further they are reduced with nuclear.

All the above to answer 'why don't we use.....some other renewable technology'

Put all the above in a spreadsheet, and then look at the impact of capital cost changes, capacity factor changes fuel cost changes and so on.

And add in wave power and or other potential renewable projects.

And you will see why ex of direct and massive subsidy they are all stillborn.

• I have costed wind-farms at £3bn per GW and nuclear at a similar price

- Hinckley is capitalises at ?21bn Euro to date for 3.2GW, so it's in the ball park. Decommission is included.

** 4p a KWh, over 60 years. It's probably less than that. Nuclear cost includes fuel reprocessing and disposal *** O & M at around 5% of capital over 60 years. **** Insurance against a nuclear accident is a moveable feast and totally at the whim of government. It could add another £5-6bn.

I have not bothered with nuclear or gas downtime.

Note that I haven't spent more than a few minutes researching detailed prices BUT the salient facts are wind as cheap as nuclear' if you look at CAPITAL costs per wind-farm and ignore short lifetimes lower capacity factors and the cost of backup. It is so easy to cherry pick one or more rows and compare two entirely different things.

Note also that even at Hinckley build prices EDF are expecting a massive premium.

Note that as gas prices rise, wind looks a better deal, but nuclear looks way better.

Finally, this is a calculation I did in principle some years ago, and which convinced me that no matter what stance you took on ecology and green issues, shorn of prejudice nuclear was far and away the best bang for the buck if you didn't want to rely on imported gas and wanted to reduce emissions. In other words I was no particular fan of nuclear and no particular enemy of renewables *until I did these calculations*.

I believe it was a calculation that the late David Mackay took to DECC (I sent it to him) and is the reason why there was such a big push for nuclear.

You can in principle extend such a spreadsheet to add in what hydro exists, and to develop an optimal mix of generating technologies as DECC used to do on their website IIRC.

A few passes myself had me convinced that the no brainer was to drop intermittent renewables altogether, and go for a mix of coal and nuclear baseload, gas doing load following, and hydro and pumped being used to cover short term peaks or in the case of hydro, to make best use of excessive rainfall.

As gas prices rise, the ratio of nuclear to gas should rise.

Note that the top ranked energy company in the world is Gazprom

Note how little renewable addition affects gas consumption, but how much nuclear does.

Note therefore how much Gazprom stands to lose if nuclear and local fracking are developed in Europe.

Note that Greenpeace grew out of CND, a Russian state sponsored anti-nuclear (weapons) site, and how that morphed into anti-nuclear power station actions.

Note that Gazprom grew out of a state owned power company.

Note that Germany is the most anti-nuclear country in Europe. Notre that Mrs Merkel worked for the East German communist state before she became Germany's chancellor.

Well that is the best answer to Brian's question I can come up with.

[tim...]

I believe that you are being overly pessimistic, the turbines inside may have a lifetime of 20 years, the structure that supports it significantly more than that

the turbine inside does not represent a significant part of the build out costs

the last time that I looked we don't routinely need to replace offshore light houses every 20 years, they have a lifetime in hundreds. It would be foolish in the extreme not to build offshore wind turbines the same way

tim

[Rob Morley]

ISTR a system that used the air above a column of water to turn a turbine.

[Chris Hogg]

What, with 6ft thick walls (10 ft on the lower courses) made of granite blocks, individually cut and interlocking both laterally and vertically? E.G.

The so-called 'rock lighthouses' (so-named because they stood on isolated pinnacles of rock several miles from the shore) relied on their weight for keeping them in place, hence the use of very large amounts of stone. The Bishop Rock lighthouse, to the West of the Scillies and shown above, is about 150 ft high and weighs a little short of 6,000 tons. It can get rough out there

[Tim Streater]

So have all the offshore turbines been built to that spec? Somehow I doubt it, dunno why.

[Andy Burns]

They're "grouted" into place a bit like the Deepwater Horizon pipework

[tim...]

It's not necessary to use 19th century building techniques to get the same strength

If we did the 21st century tallest sky-scrapers would have walls on the lower floors that occupied the complete footprint of the building to take the weigh of all the floors above them

tim