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Martin![]() |
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Veteran Posts: 275 ![]() ![]() ![]() ![]() ![]() | There's been a bit of e-mail debate about the proposed new wind farm on the south side of Ben Wyvis, which maybe deserves a wider audience, so will copy and paste it here. Starting with Energy4 All's request for people to support the planning application: A New Wind Farm Co-operative in the Highlands? APPLICATION TO DEVELOP CLACH LIATH WIND FARM WITH 17 TURBINES ON LAND AT SWORDALE MOOR, EASTER ROSS As members of existing wind co-operatives in the Highlands we hope you will be pleased to hear that another opportunity for a new wind co-op is being proposed. As with Skye, Great Glen and Kilbraur, the co-operative will offer individuals in the region an opportunity to invest in this project should it receive planning consent. The 17 turbines, with a generating capacity of up to 42.5MW is currently in the planning system and we are asking our members to show their support. The planning application and supporting material can be viewed at http://wam.highland.gov.uk/wam/applicationDetails.do?activeTab=summ... Should planning permission for the development be granted then the co-operative will offer local people the opportunity to invest in the turbines through a public share offer in the same way as the other co-ops. This will be another great opportunity to join and invest in a wind farm and make a tangible response to the serious challenges of climate change and fossil fuel depletion that we all face, while receiving similar returns that you currently enjoy. There will also be a generous community benefit fund available to local communities I’m sure you are aware that there can be some local opposition to renewable projects and supportive letters, however brief can make a real difference at the planning stage, though please remember that the more personalised you make your letter the greater impact it will have. Also if you choose to make any comments about the environmental impacts please make sure you have satisfied yourself first by viewing the project documentation which can be found online at the above web address. It would be helpful if responses could be submitted this weekend if possible as the closing date is Monday 25th June, however they will be accepted after this date provided they arrive before the planning officer writes his committee report. | ||
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Martin![]() |
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Veteran Posts: 275 ![]() ![]() ![]() ![]() ![]() | The overwhelming majority of Culbokie residents are opposed to the scheme ("overwhelming majority" based on survey work carried out by the Community Council). I think the main reason is the visual impact on the views of Ben Wyvis from the north side of the Black Isle, although there is also a feeling that the cumulative visual impact of wind farms from here is enough! Personally I think wind energy has an important part to play in the electricity generation of the country, but it has disadvantages too, so I don't think it's wise to support all wind farms on principle. | ||
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Martin![]() |
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Veteran Posts: 275 ![]() ![]() ![]() ![]() ![]() | A couple of comments in favour, from John: "Interesting response from Martin (and Culbokie). What's the problem with the visual impact? Swordale is some way away, and in general, I actually like turbines! Better I think than more dirty power stations that happen to be out of sight and out of mind. " And Maggie: "I was not popular at Culbokie last week because I signed in favour of the wind farm. My view is that each time I see wind farms I celebrate another bit of carbon saved--it may be plugging holes in a leaky sieve but my hope is that every bit of renewable energy we generate helps a little. As far as I am concerned they can be anywhere sufficiently far away from housing. I love wild places but climate change is so serious we have to compromise--what is the use of a good view if all the low lying villages on the Black Isle are flooded--to say nothing of Bangladesh We in the west need to take resposibility for the damage the industrial revolution has caused Apart from that I find them quite pretty." | ||
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Martin![]() |
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Veteran Posts: 275 ![]() ![]() ![]() ![]() ![]() | My own thoughts: For what it’s worth, my view is that the total GB wind farm capacity installed, plus the amount in construction, plus the amount consented, is about the same as the minimum electricity consumption in Great Britain (around 20 GW). So we’re approaching the point at which it is possible, on a windy night, for the generation from wind turbines alone to exceed demand. That itself won’t be very likely for a while, but taking into account the inflexibility of nuclear generation and some gas-fired power stations, I think we’re going to hit quite serious problems from the proportion of uncontrollable generation in the grid. So we’ll need to shed generation (i.e. use a dump load or turn some of the wind turbines out of the wind) when it’s windy, and on the other hand the only option on the table at the moment to add generation when it isn’t windy is more fossil-fuel power stations. So my view is that we should be focusing more on (1) ways to accommodate uncontrollable forms of generation (i.e. storage, demand management, etc.) and (2) ways to reduce the amount of electricity used, and, at least until we’ve done quite a lot more work on those things, I think it would be better not to pursue the more intrusive sites for wind farms. I also have a bit of a nagging concern that we are heading for much bigger transmission losses as we take our electricity generation further from centres of population, and I’m not sure that has been given enough thought! Strangely, one of the arguments used in favour of windfarms is that the current power stations waste around 60% of the energy used (true) and the implication is that much of that is transmission losses (which isn’t really true, transmission losses at present are around 8%). But with coal- and gas-powered power stations it was relatively easy to put them close to big cities to minimize transmission losses. With wind farms, you have to put them where it’s windy, which isn’t generally where people live. | ||
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Martin![]() |
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Veteran Posts: 275 ![]() ![]() ![]() ![]() ![]() | John again: "This is turning into an interesting debate. How about we set up a public debate or a Windfarm Question Time ? I bet there'd be a good turn-out for that. I have talked to people I work with at SSE about transmission loss over distance and they say it is fairly small in fact (but then, they would!). I still feel it would make sense if more turbines could could be sited near the major cities offshore - most of our major urban centres are on the coast. One thing we have plenty of experience of in the highlands is pumped storage and I can't really see why all our hydro-electric stations couldn't be converted to pumped storage to even out the supply of electricity. I'm not really convinced by the argument that we need gas and nuclear to keep the lights on. The other thing I hope will happen over the next few years is that wind generation will become many times more efficient so the same no. Of windfarms could produce much more electricity. Over-capacity is not a problem if it is geographically spread over a big area - if it's not windy in one place, it probably is somewhere else - so that should help to balance the load as well. Also, we shouldn't underestimate the impact that LED lighting and other efficient ways of reducing demand will have. My latest LED downlighters use a tenth of the electricity of halogen equivalents." | ||
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Martin![]() |
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Veteran Posts: 275 ![]() ![]() ![]() ![]() ![]() | Anne: "We probably need to change the tariff system from just a cheaper rate at night to a cheaper rate when energy generation is higher. This should be possible with smart metering. Already in America they are making use of excess wind generation to manufacture ammonia and nitrogenous fertilisers which would make a lot of sense. There also seems to be more possible with small(ish) scale hydro than is currently happening (through talking to a guy on the train). My understanding is that hydro can be used together with pump storage to manage peaks in demand. Solar also helps fill in some of the troughs in wind generation. We're probably aiming to overshoot wind capacity and if we export some to Europe with super-connectors and I think that will be a much bigger pool to spread out wind generation. There already seem to be inter-connectors between France and Netherlands up and running 3000MW capacity in total with more planned. I don't think it's too much of an issue if occasionally potential wind energy has to be lost short term if it means less coal is burnt in total. Nuclear generation does seem to able to be ramped up and down a bit. Probably tidal lagoons would help as presumably the water can be let out at different rates according to demand. Certainly reducing demand generally makes sense whatever else you do." | ||
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Martin![]() |
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Veteran Posts: 275 ![]() ![]() ![]() ![]() ![]() | My comments on John's: It’s true that existing transmission losses are quite small – but I think this is likely to change if we concentrate too much on generating electricity in the Highlands for use in the Central Belt or further south. The pumped hydro question – you need a reservoir at both the top and the bottom of the HEP station to do pumped hydro, and my understanding is that there are very few suitable sites. I think the losses from pumping water up to let it run down again are about 30%, so it isn’t a complete no-brainer, even where it’s possible. Nuclear really isn’t any help in dealing with the inconsistency of renewables, it’s difficult to change the output. In fact, the UK government’s plan is to use nuclear for pretty much the whole of the base load – in which case renewables and fossil fuel power stations somehow have to meet a varying load of between zero and 40 GW. As far as I can see that’s only going to be possible if someone gets their skates on with carbon capture and storage and/ or utility-scale electrical storage and/ or demand-side management. All of these are possible, but none of them are commercially available on the scale we need. There is a physical limit to how efficient wind turbines can be - essentially, if you could take all the energy from the wind, the air would stop immediately after the turbine and cause a wind pile-up. I'm sure there must be more that can be done, but most of the development these days seems to be directed at fewer, bigger turbines. Spreading turbines over a big area certainly evens out the peaks and troughs in output to a degree, but it doesn't make the output controllable. And the harder you try to spread the turbines over a wide geographical area, the more you put them in less windy places. There's a huge amount that could be done to reduce consumption, lighting is a good example, but we're not really seeing a reduction in per capita electrical use, in fact the government is encouraging a doubling of electricity use because they want us to switch to heat pumps for heating (mostly replacing gas) and electric vehicles. Also, in recent years, any gains from more efficient appliances have been exceeded by increasing numbers of appliances, and reductions in the average household size. And fridges are quite a good example of another issue, manufacturers have to give an energy rating, but this is based on the size of the fridge - so getting a massive A+ rated fridge to replace a smaller, less efficient one is quite likely to increase electricity use. | ||
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Martin![]() |
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Veteran Posts: 275 ![]() ![]() ![]() ![]() ![]() | And comments on Anne's (running out of steam here, so this will be brief!): There's an awful lot that could be done on electrical storage, reducing/ managing demand, and using surpluses from wind generation. In addition to the examples Anne gives: With storage, there's a project recently announced to trial heat-pump technology on a utility scale - the idea is that surplus electricity is used to create a temperature difference of around 660 deg C between two large containers of crushed rock. Then when the wind drops, the process can be reversed, using the temperature difference to generate electricity (see http://www.isentropic.co.uk/our-phes-technology for more info). And in Denmark I believe they are using surplus electricity to create massive heat stores, which can then be used in district heating systems - but of course we don't have district heating systems. Quite a lot of work has been done on altering the timing of some electrical loads (typically cooling and pumping) to suit peaks and troughs of generation, and this seems to work well, although there are only limited applications - e.g. lighting and cooking really need to be on demand! The ability of PV to balance wind is quite interesting. The total amount of generation plant needed is determined by the maximum anticipated demand, and of course that happens in winter, after sunset, so PV doesn't reduce the amount of other generation needed at all. However, potentially it can reduce the amount of fuel used in the other generators. But the point I was originally making was that all these things are possible, and there has been some progress, but on a tiny scale compared with what will be needed. The challenge of balancing electrical generation and demand will increase rapidly as we get beyond 20% or so from renewables, and it seems to me we ought to be putting resources into that before we build the more contentious windfarms. | ||
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glacio![]() |
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Member Posts: 32 ![]() | What I like about tidal energy is the predictability of it. True there is a fortnightly cycle due to the phases of the moon, but the time of maximum tidal flow each day varies predictably around the whole UK. High tide takes 8 hours to sweep from Oban to Dunbar around the north of Scotland. By careful positioning and scale of size of turbines the daily tidal cycle could be well dampened down. Tidal flows essentially repeat themselves each six hours although the direction has changed so Scotland alone could have a "baseload" from tides. However I am unsure sitting here just how much capacity that could bring. Martin makes a very good point about the need for our electrical generators to meet maximum loads. In UK we still think of this as being a winter requirement. But remember that in New York, Toronto and much of the warmer developed world this occurs on the hottest summer days when air conditioning is working flat out. God help us that climate change will push our temperatures up so far. BUT, BUT, BUT, there is an increasing acceptance by the retail establishments that we must shop in air-conditioned retail parks so I wonder how much of the power needed for that comes from electricity. And maybe the sun is blazing at the same time, so PV has its place there. | ||
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Martin![]() |
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Veteran Posts: 275 ![]() ![]() ![]() ![]() ![]() | Predictability is certainly helpful, but what we really want is controllability. And it's worth bearing in mind that over 50% of the UK's tidal energy potential is in the Pentland Firth. so the scope for siting tidal generators around the coast to give a constant output is limited. Then again, the Pentland Firth isn't the easiest environment to work in, so maybe that statistic isn't so relevant! | ||
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David Franklin![]() |
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Regular Posts: 80 ![]() ![]() ![]() | I'll try not to drift to far off thread this time, but i have a quick question about wind turbines \ farms in general. Given that renewables are part of the "Green Ecomony" and the "Green" economy is just the same ecomony but in a different colour. Given that Scotland has the lion share when it comes to wind and tidal in europe and with plans for a european SUPERgrid. At which point do we say we have built enough. I have heard calls for 30,000 to 50,000 on and off shore turbines to maintain business as usual levels of electricity. That to keep the lights on in Scotland would require 5,000 turbines. But if renewables is Scotlands new Oil would they ever want to stop building them? That a side I agree that you need to build wind Turbines where the wind and people are in the same place. I don't agree with building masses of infrastructure to transport the energy to "market", not because of energy losses, but because of the costs and potential difficulty of maintaining it. Finally Electricity is a luxury, it is not necessary to sustain life. We have only had it for 200 years, just like oil. So build the turbines on Ben Wyvis, build them on the Black Isle, on the Cromarty Sutors and up and down the Moray firth, perhaps it will help us to remember the true cost every time we leave a light switched on. | ||
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John Wood![]() |
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Regular Posts: 79 ![]() ![]() ![]() Location: Cromarty | I like David's final comment! | ||
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