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The farms, if all 10 are completed, will generate 20MW, enough to power 10,000 homes.

Well at least it's a contribution.

It's looking like energy efficiency and carbon rationing will be a big part of the future.

Quintus wrote:

The farms, if all 10 are completed, will generate 20MW, enough to power 10,000 homes.

Well at least it's a contribution.

It's looking like energy efficiency and carbon rationing will be a big part of the future.

Indeed, though most of the time, extra capacity is simply additional. I would like to see replacement and reduction of capacity instead.

Indeed, though most of the time, extra capacity is simply additional. I would like to see replacement and reduction of capacity instead.

+1, trouble is, its not bling enough and no bugger is interested.

[quote="Quintus"]

Nice idea, but Cornwall isn't very big compared with the kind of land areas you find in the U S of A

RenewableCandy wrote:Nice idea, but Cornwall isn't very big compared with the kind of land areas you find in the U S of A

Bummer. Go round up a century or two of shale gas and use that instead?

Of course, new developments in technology are occurring all the time and PV could seize a good slice of the renewables market eventually because of its suitability for small area applications (home and agricultural installations, etc.).

Nonetheless, I think the answer globally is solar thermal with molten salt energy storage systems transmitting power over high voltage DC. In the US, while there are now about 2,776 conventional power plants (almost all burning ancient sunlight in the form of fossil fuels), just 100 solar thermal plants each 10.5 (16.9km) miles on a side would satisfy the electricity needs of the whole country.

Now, granted, RenewableCandy's comment makes a good point that the sort of land area we have in the US just doesn't exist in the UK, but that's where the united multinational character the European Union comes in. Projects could be done on a cooperative basis between nations and could be constructed on a massive scale in Spain, Italy, and the south of France and transmit power all over Europe and the UK.

Check out this interesting new technology in mirrors for solar thermal that could greatly cut the cost of building plants and the drop the total cost per kWh to around five cents:

http://www.ecogeek.org/component/content/article/3090

Here's a little more data on the potential of solar thermal:

http://2greenenergy.com/solar-thermal-leader/2534/

In my estimation, solar thermal using molten salt for energy storage resolves the baseload debate that has precluded massive solar projects from serious consideration in the past. Energy storage remains a solid barrier to PV as a total energy solution.

My other specific doubts on PV are a) the production processes for crystalline silicon take up lots of energy, and the gradual nature of the growth rate of the feed stock prevents rapid scale-up, b) amorphous silicon has a low efficiency and is prone to light induced metastability, c) there are toxicity risks with large scale production of cadmium telluride cells, and there are potential resource limitations - also the notable the technology is in its infancy, d) there are also toxicity issues with CIGS modules, and increasing deposition rates deplete efficiency.

Solar thermal/molten salt can give the world a total solution for all our electricity needs fairly quickly and very sustainably. It'll get us off coal, fuel oil and gas fired power plants. It'll also prevent us from going down the nuclear path, which is neither safe, cheap, clean nor sustainable.

We can also readily ramp up solar thermal in a relatively short time to meet the additional demands of an all electric transportation infrastructure for mass transit, personal transportation and shipping.

Here's some info surrounding those options:

http://2greenenergy.com/electric-vehicle-adoption/2890/
http://2greenenergy.com/epa/3003/
http://2greenenergy.com/paradigm-shift/2668/

Consider the fact that 80% of the world's oil is within the top 16 oil nations, and over two thirds of that oil is in the rather-less-than-stable Middle East. With the rapid growth of the middle-class in India and China - and all the energy demand we'll see there - we can't afford to delay the pursuit of a total answer to our need for fossil fuels. This is an especially pressing reality when the only rational and reliable nuclear reactor is that great yellow ball we travel around every year - we just need to plug in.

The moment we needed to act was three of four decades ago, but now is so much better than never. I don't think we can allow ourselves to spread our investment capability across a vast array of technologies with handicapping challenges. I'm of the firm conviction that we must identify one or two solid, proven solutions and back them 100% across the globe.

I'm really thankful to PowerSwitch for circulating information on energy alternatives and providing a venue for public discussion and info exchange - if we humans put together an answer in time to avoid further like the one we're suffering in the Gulf of Mexico, it'll be in part because of fabulous sites like this one.

Craig Shields, Editor, 2GreenEnergy.com

Welcome to PowerSwitch, Craig. It's good to have a post from someone the other side of the pond that makes sense.

As you doubtless know, there are schemes afoot in Europe to harness solar thermal on a large scale, notably Desertec.

I'm not sure that I agree with you when you say

I don't think we can allow ourselves to spread our investment capability across a vast array of technologies with handicapping challenges. I'm of the firm conviction that we must identify one or two solid, proven solutions and back them 100% across the globe.

Putting all one's eggs in one basket may not be wise and I'm wary of any suggestions of 'total solution' especially when big technologies are involved.

And why single out Gaelic folk songs? The waulking songs derive from the time when textile technology involved a community of women sitting round a table pounding the urine-steeped cloth whilst singing. No petroleum involved. Finding ways to live well with less energy must always be the first approach.

[quote="Craig Shields"]

biffvernon wrote:Putting all one's eggs in one basket may not be wise and I'm wary of any suggestions of 'total solution' especially when big technologies are involved.

Well this is the brunt of it, isn't it. There are now a series of ways that we can use renewables to produce electricity, and thankfully, they're spread so that different climates can make use of what is available to them. So we have hydro, tidal & wind in Scotland, hydro & wind in Wales, biomass in the UK, PV in sunnier climes, etc...

Welcome to PowerSwitch Craig. That's an interesting and informative first post. I hope you'll stick around and continue to contribute.

But...

Craig Shields wrote:... but that's where the united multinational character the European Union comes in. Projects could be done on a cooperative basis between nations and could be constructed on a massive scale in Spain, Italy, and the south of France and transmit power all over Europe and the UK.

what are you? Are you some kinda Comm-un-ist, boy?

contadino wrote: ...biomass in the UK, ...

Don't forget wind in, I presume you mean by the UK, England. There is a huge wind reserve in Offshore England as well as tidal, without a barrage, in the Seven Estuary. There is also a significant, though not large, hydro potential in the England's rivers.

Anaerobic Digestion is also starting to make its presence felt in the agricultural community and, when this starts using domestic waste as well, will increase its potential. This is important as it will also provide an alternative to gas based fertilisers.

Rather than sticking to a few technologies as Craig suggests, we need to use whatever is available to increase the efficiency of use of all our resources. As in nature, the waste from one process should become the food for another, ad infinitum.

Spreading energy generation is also important as it minimises distribution and fuel transport costs, it enables the local use of waste heat, increasing the efficiency of fuel use, it increases local self sufficiency and stability and reduces the high flows of energy in national grids. If we can get away from the gigawatt sized power stations of old we get rid of large fuel transport requirements, the high grid losses and the huge waste of heat and inefficiencies of these plants.

No, Craig! Use anything and everything, as long as it is efficient and environmentally clean.

The storeage of solar thermal energy in molten salt, or by similar means, could certainly be useful, but remember that it entails very substantial costs, both for the storeage facilty, and for the larger collector array that is required to make up for storage losses.

The efficiency is rather low, since the molten salt is used to raise steam to operate a steam turbine.
The operating temperature/pressure would be lower than in modern thermal power stations, and the efficieny consequently reduced.

Although sunlight is free, efficiency still matters since a low effeciency requires a larger collector area which is certainly NOT free to build or maintain.

Large scale PV or solar thermal takes up considerable land that may be required for other purposes.
Smaller installation may of course be placed atop existing structures and therefore take no additional land.

Such schemes may not be the best options for the UK since bright direct sun is required, of which we have far less than many other places.

[quote="adam2"]