Re: [Phys-l] Efficiency problem

[Hugh Haskell <haskellh@verizon.net>]

At 23:35 -0700 05/28/2010, Bernard Cleyet wrote:
> This is rather old hat, as it's a means of saving on investment in 
> additional power stations, by storing power in fallow time for use 
> when needed.
>
> "The first use of pumped storage was in the 1890s in Italy and 
> Switzerland. In the 1930s reversible hydroelectric turbines became 
> available. These turbines could operate as both turbine-generators 
> and in reverse as electric motor driven pumps. The latest in 
> large-scale engineering technology are variable speed machines for 
> greater efficiency. These machines generate in synchronisation with 
> the network frequency, but operate asynchronously (independent of 
> the network frequency) as motor-pumps."
>
> http://en.academic.ru/dic.nsf/enwiki/168432
>
>
> I first heard about its use in France, fifty? years ago.
>
> http://www.erth.waikato.ac.nz/staff/bardsley/download/pumped_storage_note.pdf
>
>
> Here's wiki's list:
>
> http://en.wikipedia.org/wiki/List_of_pumped-storage_hydroelectric_power_stations

Peter's question was about the possibility that it could violate the 
First Law. It doesn't. It is true, though, that if it is not linked 
to a renewable source of energy production, that it doesn't do much 
to help the CO2 emission problem. All it ever does is enable the 
electricity supply to be smoothed some to conform with the demand 
curve, which it is difficult for thermal production to do.

It may be old, but it's still a viable option, currently in use as 
the wiki article shows, and available for future use to back up 
systems where renewables play the major role in producing most of the 
power (coal-free and nuclear-free). Here's a proposal that takes 
advantage of already available pumped storage to fill in the gaps in 
a proposed all-renewable power production system for North Carolina: 
<http://www.ieer.org/reports/NC-Wind-Solar.pdf>.

It is especially viable where existing high- and low-level reservoirs 
lie close to each other, so that water can be quickly pumped from the 
low to the high reservoir for storage and flow back to the low 
reservoir for generation. The eliminates much of the initial capital 
costs, which usually become prohibitive if one has to start from 
scratch.

Limited because it is not likely that any entirely new facilities 
will be built due to excavation costs.

Hugh

--
Hugh Haskell
mailto:hugh@ieer.org
mailto:haskellh@verizon.net

So-called "global warming" is just a secret ploy by wacko 
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