feargach, I haven't looked up any UK prices. What's the point? If we have substantial interconnection with the UK and Europe then there is absolutely no need for PSH. Our surplus generation, whereas large in the context of the Irish grid, would be a drop in the ocean in the context of the demand in the UK and Europe. Are you saying we should invest in both interconnection and PSH?

As I have repeatedly stated the cost to build Turlough Hill today would be enormous. The cost to build Turlough Hill with an upper lake big enough for large scale energy storage (remember it is not designed for this at the moment) would be off the scale. Remember, if renewable energy is ever to stand on its own two feet without subsidies it needs to compete with the generating costs of plants such as Moneypoint. At the moment it isn't there and wasteful spending like this will push it even further away from that eventuality.

Dave M I agree but my arguements are more fundamental.

I am simply cosidering the energy balance of the process. I have shown that to use these storage devices we will loose nearly half of the energy that was originally generated if not more. Regardles of the final cost, this sort of wasteage is unsustainable which is why these devices are used rarely and why in comparison quick startup gas plants are used far more often.
Until any storage device can get to efficiencies of 85% where they are in the region of direct transmission (91% efficient for US) they are not viable. Because as you point out for Turlough hill (and this goes for other storage devices) the cost are truely enormous.

I approach any engineering problem in this way because my goal is energy efficiency. Low cost while acceptable in many cases does not gaurntee efficiency e.g. internal combustion. So I calculate the energy then the cost. Generally speaking for our industrial partners less energy used/more efficient is always a saving.

Using my energy calc and your cost data we can easily put a thumb in the air and say not feasible. If on the other hand you said a cost of 100 million for a system 5 times bigger than turlough hill, I could see that being implemented but I would not be happy. Because to produce say 1000MW we would need 600-800 turbines instead of the proposed 300-400 for the London array.

Units of energy and power-why use watts or mulitples thereof

First remember 1 MegaWatt (MW) = 1000 KiloWatt (KW) = 1000000 watts (W).
A watt is equal to one joules of energy per second. It rates the power for a given decice. For example you have 60 watt bulbs, 1000 W (or 1 kW) microwave or 1600 Watt iorn etc.
To go from Watt to Watt hours you simply multiply the amount of watts (e.g. 1W) by the number of hours. Soo a 100 Watt bulb running for 1 hour uses 100 Watt hours.
In an industrial context we use Watts (well Mega, Terra or Peta Watts) as industrial operations rarely shut down and the price of electricity rarely changes. The energy uses is rarely time dependent or at least defined in that way.
However for a household the load is variable, you may only use a washing machine once a week for four hours etc. The enrgy uses is time dependent and that means you get peak loads and trough loads because of the variability. To cost this, it is much easier to fix your Watthours to a set price rather than your Watts.

In any cases these units are interchangable and what ever your analysis you can use either. However power in Watts and not powert*time *watthours) is the standard. Take a look in your kitchen.

The key issue is whether or not this idea of building several Turlough Hills is sustainable. Because of the astronomical energy loses as I have shown that abound from this process, environmentally and economically this idea of several more is not. We would have to double our energy generation to use them. Indeed consider the US. PSH is used for only 2.5% of their grid when operating (Remember we need to fill the resevoir). In that sense I would hardly classify PSH as necessary infastructure.

Right now Ireland needs to begin its alternative energy infastructure. Just building the alternative sources would be a start and that is what Ireland must concentrate one now.
More efficient means for PSH are being investigated as well as improved batteries or

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If the question were simply one of efficiency, we would build a nuclear station or a series of gas fired stations. Since the former is not possible and the latter would increase our dependence on imported gas we are left with developing windpower to as large a scale as possible. In the context of having too much power when we don't need it and not enough when we do, pumped storage has to be considered as part of the mix and as such, it should be considered as part of the cost of large scale use of renewables. Again, the basic question is do we have sites which are suitable for pumped storage? Long before energy became a subject of popular discussion, the ESB investigated possible sites for hydro stations and pumped storage as part of their diversification program.

Here's an interesting article: Power storage plan a boost to wind farms

Enerco, a wind power operator, plans to build 2 70MW PSH facilities in Cork at a cost of €280m.

According to this presentation, one of the 70MW plants has an upper resevoir capacity of 1.5m cubic metres, which makes it of a similar size to Turlough Hill (2.3m cubic metres).

Well that's all very well in practice, but haven't they heard what DaveM has to say

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When you see the words "Mises" or "Hayek" in someone's post, just ask yourself: do I really want to ban paper money and go back to gold?

You have to pity the kind of people who buy into conspiracy theories. I find the following to be the saddest words on the internet: "Re: connection between Bilderberg puppet lady gaga and viral outbreak in ukraine "

Nice to have this being discussed now on Pat Kenny radio program.

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There are times when you are simply required to be impolite. There are times when condescension is called for!
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You can't build a smart economy based on dumb decisions.
- Richard Bruton 18/12/2008