"Green Britain Gears Up for Climate Change Battle"

[dan_aka_jack]

Here's a really rather encouraging article about the UK's plans for renewable energy:

http://www.renewableenergyworld.com/rea/news/story?id=51658

The goal is ambitious: to install 33 gigawatts (GW) of wind power capacity in the next ten years to supply electricity to 25 million homes.

The means are unprecedented: to build about 7,000 offshore wind turbines around Britain's coastline.

...

Last Monday (February 18) UK Environment Secretary Hilary Benn said that a Climate Change Bill currently going through parliament could contain a mandatory target for cutting carbon emissions as high as 80 percent by 2050 if an independent expert panel recommends this in response to scientific evidence that climate change is happening more quickly than thought.

Critiques?

[dan_aka_jack]

oooh... another optimistic article here:

Government opposition to Feed-in Tariffs softens

The government has signalled it will consider introducing a German-style Feed-in Tariff to promote adoption of onsite renewables as part of a major new green energy consultation

[NickW]

2 offshore wind turbines comissioned everyday for the next 10 years

 

[martin]

yeah right!
I'm totally underwhelmed - doubtless the german type tariff will only be available to those buying equipment supplied by companies in a nice cosy cartel........and there'll be another layer or three of bureaucracy running off it's back.....
And as for billions of offshore turbines - cobblers! - the only reason they're offering this sop to green opinion is so they can slide in their ACTUAL plans for our future under the guise of being "part of a green solution" - ie ATOM POWER........then the windfarm plans will be "found flawed", severely curtailed, or just quietly dropped
(unless Mr Wickes has shares in Vestas as well as Windsave........)
I don't trust this lot any further than I could kick them!

[renewablejohn]

for all you cynics

www.wired-gov.net/wg/wg-news-1.nsf/lfi/158091

Eco friendly ratings for all new homes

sounds like jobs for the boys

[martin]

there's your 3 layers of bureaucracy (and if Caroline Flint runs true to previous form, at least 3 layers of hypocrisy and dishonesty to boot - toxic bloody harridan!)
And what pray, precisely is a "carbon zero" home when it's at home?........that'll be no concrete at all- everything brought to the site by sailing barge or horse-drawn transport! - yeah right!

[renewablejohn]

Martin

I did warn you the article was for cynics only

[Bob]

Martin,

As a serious amateur cynic I have to acknowledge the presence of a true professional.

NickW's quick bit of math ought to be done by more people more often.  So many times I have read an article that includes a few numbers or a bit of stats.  When considered rationally it rarely makes sense.

[KenB]

Jack,

"The goal is ambitious...."

The goal is technically flawed.

It is technically impossible at this time to get 33GW of intermittent wind power to interwork efficiently with the existing power generation plant on a national grid that has a capacity of 78GW.

If 1000 1MW  (1GW)  turbines start spinning off the coast of Scotland, and this occurs at a time that there is low demand on the network, then  1GW of conventional power will have to be removed from the grid in order to maintain balance. Clearly it is impossible to shut down a CCGT plant or a coal/nuclear fired power station, at the drop of a hat, so the excess power will have to be dumped somewhere. 

This could mean dumping it to electric storage heaters or electric water heaters, but its hardly a practical solution. 

Instead the wind generated power would need to be stored, for example in a pumped storage scheme (like Dinorwig - but very much larger), so that the energy produced could be used at a later time when the grid demanded it.

For this you need  to start looking at Scottish lochs and find two suitable candidates that are separated by a considerable vertical height.

The problem is exacerbated with the more wind power that you add to the grid, and the proposed 33GW could on average supply about 10GW to the grid.  So you turn off 10 large power stations, only to find that you are becalmed a few hours later.

In Ireland, they have had to use "quickstart" diesel generators to balance the unpredictable nature of the  wind generators.  Burning diesel when the weather is calm is probably not the most carbon neutral solution.

The problem of managing the grid is difficult enough without the unpredictable nature of wind.  Existing CCGT, coal and nuclear plant can not easily be shut-down or restarted efficiently.

A separate power management grid would be needed for the wind turbines, possibly by having them pump water into the reservoirs of existing hydro schemes, or by creating a massive new pumped storage scheme, on a scale that has not yet been seen.

Dr. David MacKay has some thoughts about suitable locations for large pumped storage schemes in his forthcoming book "Sustainable Energy - Without the Hot Air"  You can download a draft here

(Section L. Storage page 311 onwards)

http://www.inference.phy.cam.ac.uk/sustainable/book/tex/cft.pdf


Ken

[dan_aka_jack]

Yes, I'm sure you're right.  I believe Texas has recently had black-outs because their sizable windfarm stopped generating due to no wind (although the Texas grid points out that they would normally be able to cope but they had some other problems as well).  Can't find a link, sorry - it was listed in one of the "drum beats" on TOD a few days ago.

I'm not sure it's entirely correct to say that wind power is completely unpredictable.  Weather forecasters should be able to give at least a few hours notice (if not a few days of notice) of changing wind conditions which is plenty of time to get "hot standby" capacity up-and-running and might be long enough to put running stations into standby; or to stop drawing 2GW from France(!).  In a way, a wind farm is actually more reliable than a traditional power station.  If a coal plant has an unexpected catastrophic failure (which does happen) then it'll take 1.5GW off-line immediately with very little if any warning - and the grid copes with that adequately (by shedding load immediately, bringing online standing reserve diesels and spinning reserve and then firing up hot standby capacity).

This is an interesting article on control of the national grid (although it doesn't seem to discuss what happens if there's excess supply):

http://en.wikipedia.org/wiki/Control_of_the_National_Grid_%28UK%29

Prof David MacKay's book looks really interesting.  Haven't had a chance to read much of it yet though.

[KenB]

Jack,

I was just about to post the same Wiki link     You beat me to it!

http://en.wikipedia.org/wiki/Control_of_the_National_Grid_%28UK%29

It seems that we currently have the control processes in place to adjust the grid supply by +/- about 2GW fairly rapidly, with a further 8.5GW hot standing reserves available within 30 minutes to 2 hours, but not the proposed potential +/-10GW that could arise from a 33GW wind generation installation.

There is also the 2.25GW of diesel generators and about 2GW of load that can be turned off almost immediately, such as industry, should things start to get a bit wobbly.

The control of the grid is clearly already quite a complex problem and not yet set up for the fluctuations that could arise from the unpredictable nature of renewables. A windfarm can become becalmed very quickly too, and vary considerably from zero output to full rated capacity - and everything in between.

Perhaps if they ever build the Severn tidal barrage, they could use the excess grid power (from wind) to pump water in and out of the estuary to help balance the grid.

Also there is the geographical nature of the wind power -  generally off the west coast. We are already importing about 15% of our power from Scotland via the national grid, would the inter-ties between Scotland and England be able to cope with much greater flows or would they have to be substantially upgraded  - possible as a HVDC network.

Whatever we choose to do, the grid ( implemented in the 1930s) will need substantial upgrading and we will have to find efficient means of storing large quantities of energy.  Clearly the notion that you can just add a few turbines and shut down a few 1960s coal fired plants is over-simplistic and currently unworkable.

I'm not against wind, we just have to devise the mechanisms to allow it to deliver efficiently.

Ken

[billi]

hi

this sounds intresting...  air storrage..

http://www.entrepreneur.com/tradejournals/article/167751619.html

[KenB]

Jack, List

Having read the "controlling the grid" article, I thought I'd look at the real time frequency and demand data published by National Grid PLC.

http://www.nationalgrid.com/uk/Electricity/Data/Realtime/Frequency/Freq60.htm

Interesting that the frequency varies with about 30 minute cycles, as generators make decisions whether they want to contribute to the next 30 minute charging period - or not.

Standby Diesel plant and load shedding that had been enabled to help increase the frequency is shut off, as soon as they get the larger plants operational.

It will be interesting to see what the frequency and demand does between 11am ad 1pm as all those Sunday lunches and pub meals are cooked.


Ken

[KenB]

Jack, List,

The chart about half way into this paper illustrates the variable nature of wind generation.

It shows the combined output from the west Denmark farms for a period of a week - each day being a different colour.

http://www.uic.com.au/nip38.htm

For four nights there was only 25MW output between midnight and 8am, and then for 24 hours it blew like crazy providing over 400MW of output. It is very difficult to base a reliable supply around output figures that vary by about 16 or even 20:1.

If diesel or hydro backup is not available, then perhaps we should have some other forms of distributed energy storage.

1. Batteries - could be in the form a of a stationary system or even an electric vehicle.  Having it recharged cheaply or free when the wind blows could be an incentive, but remember that those who supply power to the nation are doing it for profit, not convenience or charitable reasons.
2. Pumped storage - 1 hour of UK baseload power usage could raise a cubic kilometer of water through a height of about 12 to 14 metres.
3.  Electrolyse water or sea water to make hydrogen and other useful chemicals.
4.  Electric storage heating and immersion heaters under National Grid control
5.  Millions of washing machines and dishwashers that can be powered up remotely under the control of the National Grid.


Ken

[martin]

could it not be a case of designing for "export to grid when needed - nationally", and "dump locally?" - in that way there is no need to "beef up" the whole grid - and with careful design, could "dump" not become a misnomer?
Say there were a windfarm off the coast of Eastbourne - on a windy day when the grid's "up to capacity" all the local swimming pool heaters would kick in, vast storage heaters switch on in all the local municipal buildings, old people's homes, hospitals etc, and "local" punters have the chance to charge their electric cars/ home battery banks at a very favourable rate (and everyone has a cheap washday...)