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Post by havelock on Sept 9, 2010 14:25:52 GMT 1
Without getting bogged down in a debate about climate change, do boarders have any views on efficient energy storage systems to ensure that if we do have wind farms and other intermitent energy sources, we can ensure that we store any surplus for use at peak times?
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Post by pumblechook on Sept 9, 2010 15:53:46 GMT 1
There is no such thing as 'efficient' energy storage.
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Post by Progenitor A on Sept 9, 2010 15:58:01 GMT 1
There is no such thing as 'efficient' energy storage. Not electrical energy. Mechanical energy is easy. Simply pump water uo to a reservoir at times of low demand |
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Post by havelock on Sept 9, 2010 16:00:28 GMT 1
There is no such thing as 'efficient' energy storage. I accept your point but I believe that some are more efficient than others and the intermitent nature of some of the renewable energy forms being used currently means that energy that is surplus at that moment in time is discarded. Are there any forms of storage could be used so that this surplus energy can be stored and used when it is required? |
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Post by pumblechook on Sept 9, 2010 16:28:04 GMT 1
Obviously some are more efficient than others. The problem is that several energy conversions one after another leads to high losses overall. 3 x 90% conversions result in an overall 73%. 3 x 85% (more typical) result in 61% overall. Electric cars are particularly inefficient.
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Post by havelock on Sept 9, 2010 16:31:32 GMT 1
Obviously some are more efficient than others. The problem is that several energy conversions one after another leads to high losses overall. 3 x 90% conversions result in an overall 73%. 3 x 85% (more typical) result in 61% overall. Electric cars are particularly inefficient. Agree with all you've said there but surely discarding surplus energy is as inefficent as one can get (without actually exerting more energy to store it that it itself is)? Are mechanical means more efficient than e.g. chemical? Anyone know where there is and web sites, references where this is dicussed? |
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Post by pumblechook on Sept 9, 2010 16:37:20 GMT 1
If you want to broaden the question then is it efficient to even bother with solar or wind in the first place?
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Post by havelock on Sept 9, 2010 16:41:51 GMT 1
I didn't actually want to broaden the question in this thread as that's being discussed in the 'Environment' board (well wind is and no doubt solar could too).
I'd really like to keep this discussion to the means of storing surplus energy if thats OK?
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Post by pumblechook on Sept 9, 2010 18:09:37 GMT 1
Pump storage then.. Study Dinorwig which is not strickly speaking a serious attemp to store much energy but a short term stop gap to allow standby generating plant run up. It is intended as a frequency maintaining system. It must have cost a heck of a lot and there won't be many suitable 'natural' locations in the UK so really pump storage is not really viable economically. I think it might be of the order 85% efficient and that figure is probably the best you could ever achieve with any storage system.
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Post by pumblechook on Sept 9, 2010 18:18:03 GMT 1
Dinorwig..
Cost (mid 70s) £425M
Power... 1800 MW.
Run time, max (at max output)... 6 Hours.
Storage capacity (output). 10.8 GWh
Efficiency.. 74 % (worse than I thought)
What would it cost in 2010 money?
And what would a station cost which doesn't have as many 'natural' advantages?
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Post by kiteman on Sept 9, 2010 19:56:44 GMT 1
Some wave power systems are (designed to be) used pump water directly, uphill into reservoirs.
The reservoirs are then (designed to be) used to generate hydro-electric power on demand.
(The brackets are there because I know they have been designed, but I don't know if they have been built.)
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Post by steveh on Sept 9, 2010 20:06:28 GMT 1
All high-rise flats and office blocks need to pump water up to tanks on various floors.
Why not stick a wind turbine on the roof, it wouldn't need to be that big because of the height, and make the tanks larger than required.
This would give free pumping of the water that is usually used and once the tanks contain more water than they need a valve could be opened and the water dropped down to a turbine in the basement.
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Post by kiteman on Sept 9, 2010 21:11:00 GMT 1
... a valve could be opened and the water dropped down to a turbine in the basement. #2 son drew a plan for a toilet that contains a small turbine in the waste pipe... |
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Post by steveh on Sept 9, 2010 21:19:25 GMT 1
I'm surprised #1 son didn't think of it, it would make the design of the turbine simpler.
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Post by kiteman on Sept 9, 2010 21:28:44 GMT 1
#2 is more inclined to pick up pencil and paper - it's an excuse to avoid actually reading books at bedtime.
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