Double your fuel range!

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At present it is not commercially viable to use wind power without substantial grants from the taxpayer.

These grants are justified by the MMGW/CO2 argument.


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Not forgetting the political arguments of reducing our reliance of fossil fuel.
 
Yes

But the argument is purely political

ie

It has no relationship with the facts.

There is no meaningful saving in CO2 emissions or use of fossil fuel for the reasons outlined earlier.

Never forget

A political argument involves a politician moving his lips

And how do you know when a politician is lying?
 
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An argument of desperation.

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By attributing a position to me which I haven't expressed, you're actually having an argument with yourself. My comments were confined to the lack of predictability, and storage through conversion; the latter issue is relevant to most forms of power generation.
 
Well thanks for the lecture Dave, I do appreciate these things being 'spelt' out to me by experts.... Even if I do have an 'O' level in physics (and a few others also !)

Have a nice day. Nick
 
No problem! On reflection the comment re. O grade physics was maybe a bit unwarranted.

The trouble is that the world is full of snake oil salesmen who never seem to lack credulous customers. Even the well educated and otherwise astute seem to fall for the proposition. It's a bit like watching conjuring tricks: smart people are just as easily deceived as dopes. I suppose the point I was trying to make is that a reasonably good defense is to try to follow through what is being proposed from first principles to see whether it makes sense. In this case it was quite easy because the mechanisms employed are obvious.

It gets harder to judge when something unknown is proposed - see previous threads on machines which purport to run on "the energy of the cosmos" or some such. The nagging worry is that something unknown today is not necessarily impossible. If, 100 years ago, someone had suggested that it would be commercially practical to generate electricity through utilising the energy locked up within atoms, he would have been laughed at. OTOH the argument "they laughed at Galileo and he was right so, now that they're laughing at me, I must be right" isn't very sound either. As a general principle I still believe that if something sounds too good to be true then it probably is.
 
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"for example, tidal power is eminently predictable, but, inevitably, will only exceptionally be able to match peak production with peak demand "

Well, yes and no. Peak tidal flows occur at different times in different places so, in theory at least, it should always be possible to have peak tidal power coming from some installations in a national portfolio of tidal installations.

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I don't think a national portfolio (or even an international one) would address the problem of the reduced energy available at neaps compared with springs.


Alan
 
I'm afraid you've lost me.

Are you saying that conventional power stations have to run (at load) regardless of how much power is being generated by wind turbines, so as to provide power when the wind drops?
 
No not quite

The problem with electricity is that you have to generate precisely the amount that is being used.

To do this the grid controllers use a range of information to predict what the load is going to be at all times and then plan for the most economic capacity to match that load.

This is never totally accurate so they have a certain amount of capacity on standby. That is only generating a small amount of their maximum capacity. Most power stations, particularly coal fired, are very inefficient doing this.

When you include a quantity of capacity from wind power which is completely unpredictable in terms of how much will be available and when, the controllers have to have sufficient capacity available at very short notice to meet demand without wind power or with very little wind power. If there is an adaquate level of power from wind then there is a significantly increased amount of other conventional capacity that is running in a very inefficient way, but which cannot be taken down completely in case the wind drops.

This inefficient operating regime generates lots of CO2 for very little electricity. Big coal powered plants need to be run a full capacity to be at their most efficient.

Thats why I say that talking of "surplus" supply from wind is erroneous - the surplus is in conventional that is running at well below its most efficient capacity.

As for storage - the Dinorwic storage station in Wales needs some 300Mwatt available for about 7 hours to fill the tanks

Most windmills are less than 1 Mwatt maximum capacity. So to store that much energy would require over 300 mills going at full capacity for 7 hours which is a most unlikely occurance - during which time it is not available for its true purpose of meeting very short time demand. So what would be used instead of that facility would be gas turbine capacity - which in terms of CO2 production is probably the least efficient capacity.

In the days of the CEGB the plan was roughly 1/3 of total capacity was base load and was mainly nuclear and big modern coal stations. The next third was smaller coal stations to meet predicted demand. The top 1/3 was a mixture of coal and oil, with short term things like gas turbines and stored water to meet the real short term peaks.

The model is different now I think due to the large amount of gas capacity but the principles are still the same.

To accommodate a significant amout of capacity which is totally unpredictable into this sort of plan is almost impossible.

Does it contribute to base load - which is meant to be generating continually - it can't because the wind doesn't blow continually.

Does it meet intermediate load - again no because its impossible to call a group of windmills and say you want them on line in an hours time.

Does it meet peak load - again unless the peak of demand happens to occurs at the same time as the wind starting to blow its useless.

All you can do is let it contribute to base load but have increased capacity from other sources available at short notice.
 
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Oh

Perhaps if you clarify your position a little for me I may be able to respond more precisely.

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Eh? /forums/images/graemlins/cool.gif

Errmm, I don't think that I should need to so, any more than previously stated above. My position on this is, as stated in two (or three?) posts above, in this this thread. End of story.
 
Yet another example of the old adage "Never let the truth get in the way of a good story".

Maybe it is because I am getting old, but it seems to me that false ideology is becoming more common, despite the greater volume of information available and the seemingly higher level of education that should allow people to think through things for themselves.

Maybe it was always thus but never obvious to the peasants as they were kept in the dark.

My theory is that the pedlars of false ideologies continually re-invent themselves by jumping on board when a topic is new and shaping its development in the way that suits them. Dislodging them from their position is very difficult, particularly if you rely mainly on facts!
 
Isn't it the case that wind power, viewed in isolation, works when the wind is blowing.

Therefore, the challenge is to find standby power sources that are not carbon inefficient when standing by. Saying (a la Big Power) that wind is no good because our back-ups are inefficient is an unimaginative response.
 
It is a case of dealing with what is not what we would like it to be.

Unimaginative - perhaps, but the industry has to produce power now with the technology that exists now.

It isn't a case of "back-up" to wind being inefficient, the fact that you have to have that capacity on standby at all that destroys the argument for wind power.

Its like having to leave your car engine running all the time because if it stops you can't start it up again.

Wind can never provide the bulk of the power requirements - even if you can guarantee 100% availability of the wind to drive them you will need something like 50,000 mills. If you have a 50% duty cycle that becomes 100,000 - a completely unrealistic proposal, and more importantly a waste of money that would be much better used in other systems.

If you put the money into tidal then that power could be used in the base load because you know when its there and how much of it is available. It can be managed. Doing that can make a dent in CO2 production, but even tidal is not going to produce all of base load, let alone be able to meet the full demand.

That will continue to need fossil or nuclear.

Sorry but that is fact - however much anyone may wish that it wasn't.

If you can find a way to make nuclear fusion work, develop it into a viable production system and build and commission around 50,000 Mw of power station capacity in the next 2 or 3 years then we can solve the problem.

Until then we can make the best use of what exists or revert to the lower end of the 3rd world, because without a robust and reliable souce of electrical power thats where you will be.
 
The car analogy is a good one. Develop standby systems that can be started at the press of a button. Gas, oil, hydrogen - all would seem feasible. Especially if these were smaller, and geographically distributed (closer to centres of consumption), so that they could be manufactured as factory-built units and not as mega civil-engineering projects.

And why not 100,000 wind turbines? UK surface area is 24,250,000 hectares. That's only one turbine every 242 hectares, without taking account of offshore locations.

(A hectare is a little smaller than two standard size football pitches.)
 
Beadle, first a thank you for the well reasoned arguments you have put forward. I agree with you about the problems of wind power but came to that view through a much less expert process.

Given your familiarity with the issues do you have any thoughts on the geothermal options? No-one seems to mention them. I have no idea about how this might contribute to energy supply and is anyone working on it in the UK?
 
Thanks for that.

Presumably one of the biggest problems is the immedate storage, and then use, of electricity (as it probably always has been). Pushing water up hill is all very well, and has its use, but given the losses in the grid it is a fairly expensive option. Also the hilly places tend to be furthest from the cities.

Is there or will there be a use for 'fuel cell technology' (or something else) for smoothing out supply/demand, but maybe on a smaller scale and more locally? If this can be done then the peaks and troughs of wind etc. plus demand could then make power station supply more efficient, and make wind power more useful. Perhaps the government focus is in the wrong area?
 
Ken

It really depends on your objective.

If you want to significantly reduce the CO2 output from electricity generation (and this is the critical area - cars etc are a sideshow) then wind is not the answer. You have to take a realistic view. The level of investment in R&D to produce the systems you describe solely to justify the use of wind power is folly.

That investment would be much better put into tidal, and nuclear or even as suggested elsewhere geothermal.

The end game is electricity production it is not playing with windmills.

As for storage - again it is a question of size - Ken talks of rapid response standby stuff - and this exists . There are a number of Olympus gas turbine sets (Drax has 4) which can be on line in seconds. The problem is that they are not low CO2 machines, they burn huge quantities of fuel and are only used normally if absolutely necessary. To have to use them every time the wind dropped would not only produce more CO2 than the wind power saved (that is fact) but would rapidly wear out the machines and significantly increase costs.

Not I would suggest a good idea

As for 1 windmill per 245 heactares - I would ask how many windmills are there within the M25 - I will consider that solution when 1 machine per 245 hectares is achieved within the M25 and not before - its all very well making these statements but its always someone else who has to live with the consequences.

I don't know very much about fuel cells so I'm not best placed to comment really - my thoughts for what they may be worth again centre on capacity. Let me parallel a conventional battery, like a boat battery

a 100 Ah battery will in theory supply 1.2 kwH 12 x 100 x1/1000
In practice it would be significantly less.

The Dinorwig facility supplies 320,000 x 5 = 1,600,000kwH

Or 1.333 Million times as much or 1.333 million batteries

Set that against 320Mwatt reserve for 50,000 Mwatt supply capacity, and its less than 1% reserve.

How much would 1.3M batteries cost

How much lead would be required, and what would happen to the price of lead and how much CO2 would be produced in mining and refining it

OK thats battery - power cells are different, but they still represent a huge investment, still use a substantial amount of materials that have to be mined and refined.

I don't say it can never be a solution (though I have doubts) I don't see it as a solution today, or indeed tomorrow.

Geothermal can most certainly be a useful source of heat. A friend of mine installs a heat pump based system that can provide a useful saving on central heating.

In an area of relatively low geothermal activity I'm not at all certain as to whether it can be a viable source of power generation in the way it is done, I believe, in Iceland - I guess in the UK you would have to drill fairly deep to find high enough temperatures to make steam - It may be viable, I really don't have any grip on the numbers to make any meaningful comment.
 
Pumped Storage

I've kept out of this so far, but it might be useful to contribute a few points.

The UK currently has 4 pumped storage power stations, 2 in Scotland, 2 in Wales.

Ffestiniog is the oldest: 4 X 90MW sets giving 360MW total, opened in 1963
Cruachan was next: 4 X 100MW sets giving 400MW total, opened in 1965
Then came Foyers: 2 X 150MW sets giving 300MW total, opened in 1975
And lastly Dinorwig: 6 X 330MW sets giving 1,980MW total, opened in 1984.

You can see how set size increased over the years, just as it did in coal and nuclear stations over the same period. Other pump storage schemes, e.g. Ben Lomond, were planned, but cancelled. Since privatisation of the Electricity Supply Industry in 1990 no major generating plant of any type (other than gas) has been constructed.

Pump storage schemes have a number of uses. They can "load shift" i.e. pump during periods of low system demand and generate during periods of high demand which has obvious economic benefit. Their fast response allows them to be economically used as spinning reserve (the turbines are run in air to reduce friction then the water is let in when required) which can be brought on line in seconds to cover for loss of conventional plant. That same fast response allows them to be used for short-duration frequency control. Obviously the same machine cannot be used for all these functions simultaneously, so a bit of clever juggling by the grid operators is required. The whole business now has huge additional complication caused by the present electricity trading arrangements, but unless you're a complete electricity anorak, you really do not want to go there...

Other storage technologies have been proposed and a number of demonstration units have been built. Batteries have been discussed by others and, ironically, lead acid banks were used in the very early days of public electricity supply to allow generators to be shut down at night. Electrolysis and subsequent re-combination of 2H and O2 started this thread. Other options include compressing air in an underground cavern, spinning up a gyroscope rotor, etc. All deliver less energy than is put in due to energy conversion losses in both directions: an overall efficiency at the lower end of the 80% to 90% range is typical. (Pump storage schemes can do better than this through "cheating": it is common practice to capture streams and re-route them into the upper reservoir, so more water flows down the hill than is pumped up!)
 
Re: Pumped Storage

With regard to the original post the downside seems to be that that the energy required to split water into hydrogen and oxygen comes from the engine. This surely is not necessarily so on a boat? eg Solar panels, wind generator .. ?
 
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