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Hi Dave,
Not to prolong the agony, but according to the MacKay book I cited, the Dinorwig (Welsh) system operates at 74-75% efficiency, actually a bit better than the 64% you cite for Ludington. The argument was/is not about whether pumped storage can work, but that even if there was the political/financial will to convert more lakes, there is not enough capacity available in suitable pairs of lakes in UK with decent height offsets to provide the potential energy required to store all the surplus energy needed that way, sufficient to buffer the fluctuation in demand -- the numbers are too large. MacKay discusses the best potential lake pairs, for instance one using Loch Lomond in Scotland as the lower 'sink'.
In thinking about how to cope with this and store surplus electrical energy temporarily in some other way, one of MacKay's more fanciful ideas is that in the not too distant future we will be off the oil economy altogether and all be driving electric cars. If you had 30 million such cars in Britain, the numbers say that there then would be enough battery capacity available to use them as night-time storage if they were all plugged into the grid to recharge, when both grid demand and the price of electricity is lower.
It's ~5 years old but an interesting book.
Steve
________________________________________
From: naturens-owner@chebucto.ns.ca [naturens-owner@chebucto.ns.ca] on behalf of David & Alison Webster [dwebster@glinx.com]
Sent: Saturday, December 20, 2014 3:54 PM
To: naturens@chebucto.ns.ca
Subject: Re: Long again: Re: Long: Re: [NatureNS] light
Hi Steve & All, Dec 20, 2014
Systems which do not work well, such as the Wales site, do not prove
that pumped storage can not work anymore than I can prove, by direct
demonstration, that music can not be extracted from a violin.
For pumped storage to work reliably one must have volume sufficient to
ride out any prolonged period of calm. An account of a system which does
work,
cut from a 2012 e-mail is pasted below.
START OF PASTE
Re Ludington my letter (pasted below) to the Advertiser Editor (Not
used) contains the essentials. Also see
http://en.wikipedia.org/wiki/Ludington_Pumped_Storage_Power_Plant
START OF PASTE
Dear Editor: Sept 24, 2012
According to Warren Peck (Register, Can we trust CANWEA ads ?,Aug 2),
electrical storage is still in the research and development stage.
Well, the pumped storage facility in Ludington, Michigan was built
between 1967 and 1975, is still functioning and has a capacity of 1872
Megawatts. It has served so well that an $800 million upgrade is about to be
undertaken.
There is always room for research and development but pumped storage is
proven technology. According to Kraushaar & Ristinen (Energy and problems of
a technical society, 2nd ed., 1993) the efficiency of pumped storage is
typically 64% as compared to 36% for optimum generation by heat.
They also note that the Ludington reservoir can store 15 million kW.hr
of energy. Based on a recent article (Chron.Herald. Sept 19) the average
residence in Canada uses 10,389 KW.hr/year. So that one reservoir stores
enough energy to supply 17,000 residences for one month; hardly prototype.
Yours truly, David H. Webster 678-7824
END OF PASTE
and an account of another site from Ivan Smith, Oct 18, 2012
START OF PASTE\\\
I'm familiar with the 174 megawatt Sir Adam Beck Pump Generating Station at
Niagara Falls
http://www.opg.com/power/hydro/niagara_plant_group/adambeck2.asp built in
the mid-1950s, when I was working at the Nova Scotia Light and Power
Company. http://ns1758.ca/electric/electricpwr14.html There were numerous
reports about this large pumped storage plant in the technical journals that
NSL&P purchased and circulated among its employees. Pumped storage was not
new even then, but the Niagara plant attracted special attention because it
was/is very large. The Beck Pumped Storage Plant has now been operating
successfully for sixty years. There are dozens of such plants around the
world. --
END OF PASTE\\\\\\\\\\
In addition, as described by Kraushaar & Ristinen (Energy and problems
of
a technical society, 2nd ed., 1993), Chapter 8, the same hardware can be
used for both pumping and power generation and natural waterways need not be
involved; water being moved between upper and lower reservoirs. One system,
being constructed in California in 1993 to move water between a surface
reservoir and a lower one excavated from solid rock was designed to store
1.12 million kW.
Yt, Dave Webster, Kentville
----- Original Message -----
From: "Stephen Shaw" <srshaw@Dal.Ca>
To: <naturens@chebucto.ns.ca>
Sent: Saturday, December 20, 2014 2:00 PM
Subject: RE: Long again: Re: Long: Re: [NatureNS] light
> Hi Dave,
> A larger problem is that currently and forseeably wind is relatively small
> potatoes and intermittent, and putting in many wind farms doesn't even
> remotely average out the power fluctuations. You also mentioned somewhere
> that this fluctuation could be solved by storing electrical energy during
> an energy glut by pumping water uphill into a storage reservoir (then
> recovering it in times of increased demand by letting the water run back
> down, powering turbines). This rang a bell as this year we had visited
> the Dinorwig power station in Snowdonia Natl Park (Wales), built
> discretely inside a mountain, that operates on just this principle with a
> large water differential height of ~500 meters. It is an enormous project
> but can't even out daily fluctuations in demand even with 3 other similar
> smaller stations running. It is used these days mainly to add a surge of
> power to the national grid at the end of popular TV programs in UK like
> East-Enders, when literally millions of viewers head simultaneously for
> the kitchen to plug in their electric kettles for cups of tea -- really:
> Dinorwig alone can go from 0 to full 1.3 GWatt power in 12 seconds to cope
> with this, and can supply some power for a few hours. The turbines are
> reversed at night when electricity is cheaper, to pump water back up to
> the upper storage lake.
>
> There's some info on Dinorwig in Wikipedia, but the point of this note is
> that in looking this up, I came across a book that discusses all this with
> numbers and e