George Osborne demands massive cuts to windfarm subsidies

[An_Inspector_Calls]

Beyond initial environmental and monetary considerations, solar energy generation requires less moving parts than the other types already cited, and therefore would presumably incur less financing in its maintenance - surely a saving long-term?

Even if that were entirely correct:

1. The average UK consumption of energy for hot water heating is 3.5 MWh pa. If you were foolish enough to do this using electric power, that'd cost you £350 pa
2. By use of solar water heating you can save approximately half that power - at best 60 %.
3. The cost of a typical installation is £4,000

Work out the pay back period.
And these systems do need to run circulation pumps - factor in 50 W , running for half the year as a cost

[Dave2002]

Few, if any, of these alternative technologies provide details on their total carbon footprint during their manufacture.

This is also true of non alternative technologies and most things which we buy. Full lifecycle costs are hardly ever provided, including manufacturing costs and energy consumptiom etc. and decomissioning and disposal factors. Factors generally of interest are cost, energy and CO2 emission. The last two are correlated somewhat, but not 100%. Decisions and persuasion etc.are often based only on operating costs. Examples - railways, including high speed lines, tunnels, bridges. I'm not a great fan of air travel, and for short distances the railways are in some ways better environmentally than air travel, but if there's only modest traffic demand then air does not incur the same infrastucture costs which depend strongly on distance, and could actually be environmentally preferable.

[ahinton]

I do hope that the Treasury gets its way. The environmental pollution caused by these things is a major problem. I've recently spoken to people who are suffering from the noise generated by land-based wind turbines anything up to a kilometre or more from their homes, all of whom wish that they had been more active and vocal in their opposition to the installation of these machines, it being extremely dificult/impossible to remove the nuisance once it is in place.
Far better and I daresay more cost effective to stop subsidising land-based wind turbines and instead to spend the money on improving the energy efficiency of housing.

Agreed!

[ahinton]

Even if that were entirely correct:

1. The average UK consumption of energy for hot water heating is 3.5 MWh pa. If you were foolish enough to do this using electric power, that'd cost you £350 pa
2. By use of solar water heating you can save approximately half that power - at best 60 %.
3. The cost of a typical installation is £4,000

Work out the pay back period.
And these systems do need to run circulation pumps - factor in 50 W , running for half the year as a cost

"Foolish enough"? Not everyone has access to mains gas, you know! That said, I am not as convinced by the financial benefits of solar thermal installations (which are used mailny to provide hot water and occasionally to contribute towards heating) as i am of solar PV. I intend eventually to move to France, as some here already know and, OK, 50+ miles north east of Bordeaux is certainly an area where more can be gotten out of solar power than is the case anywhere in UK, but I've been looking at whether it's economical to have a separate solar thermal installation for hot water in addition to a solar PV one for all the electricity production in the property (which has yet to be built) or whether it would be better to use solar PV to provide all the electricity requirements including electric water heating and the outcome is that the latter wins out every time. The unsubsidised cost of an installation iwill probably be around £13,000 but with the current arrangments with EDF in France one sells electricity to the grid for around five times the price that one's charged for it, so if the property is well insulated with an efficient low electricity consumption underfloor heating system and a heat recovery ventilation system, the power bills for a year should be around minus £1,500 p.a. Payback times are always imporssible to determine because the cost of solar installations and materials will decrease the more widely they're ordered but, on the other hand, mains electricity and fossil fuel prices are unpredictable except that they'll almost certainly usually increase.

[Resurrection Man]

Certainly true, Dave, but since renewables 'sell' on their green credentials, I think it is important to know just how green they are.

Ahah....just did a quick Google and came up with this http://www.parliament.uk/documents/post/postpn268.pdf. Interestingly, the carbon footprint of windpower is pretty low..only slightly higher than the carbon footprint for nuclear..which is the lowest !

Biomass is several times higher than any comparable energy source. PV is pretty darn poor and can hardly be called green!

[Eine Alpensinfonie]

This is a topic worth debating, but it does nothing to strengthen anyone's argument by using aggressive and demeaning language.

The cost to the individual is not the the prime factor in going green. It's about sustainability for future generations.

[french frank]

The cost to the individual is not the the prime factor in going green. It's about sustainability for future generations.

Indeed. And also having possibly the greenest of green electricity suppliers gives me the perfect answer to all those competitive suppliers who want me to change to them because they're cheaper. I can just say every supplier is cheaper than my supplier. And I don't care.

In terms of quality of life, I value being able to ring them up, get straight through without having to keep pressing buttons, and have my query dealt with directly by the human being who answers the phone. It's no different from ringing up a friend

[ahinton]

PV is pretty darn poor and can hardly be called green!

On what basis do you seek to allege this?

[Dave2002]

Certainly true, Dave, but since renewables 'sell' on their green credentials, I think it is important to know just how green they are.

Ahah....just did a quick Google and came up with this http://www.parliament.uk/documents/post/postpn268.pdf. Interestingly, the carbon footprint of windpower is pretty low..only slightly higher than the carbon footprint for nuclear..which is the lowest !

Biomass is several times higher than any comparable energy source. PV is pretty darn poor and can hardly be called green!

The "greenness" of an energy supply might depend on who is judging it. There is a case to be made for supposing that nuclear generation is the greenest, as it delivers high power in abundance with limited Co2 and other emissions used in construction of the plants and running them. This assumes however that nothing goes wrong, though events in Japan in recent years have pretty much forced a rethink of that. In the UK and parts of Europe nuclear power plants may still be a good option.

Burning fossil fuels such as coal or gas is not a good option, as firstly these are not renewable, and secondly they raise CO2 levels. We could consider these to be 100% non green.

It is possible to do worse than that. The development of some bio fuels, for example for aircraft, may require the burning of non renewable fossil fuels, and produce fuels which have lower calorific value than the non renewable fuels used in their production. Thus their non greenness measure might plausibly be 130% - or could be higher. This may be necessary for experimentation and development, and possibly some applications such as fuels for military aircraft may require that.

Over time it sems likely that most bio fuels will not do so badly, and we should be able to make aviation fuel which does not require burning more fuel in manufacture than in use. However bio fuels may continue to be poor, except perhaps in some countries where they have managed to develop suitable crops which make bio fuels viable.

Wind generation I believe does quite well and gets better if done on a large scale. Small micro generators such as one could buy in B and Q are not in most cases a good option, and if installed in urban areas would annoy the neighbours. Large scale wind turbines are arguably noisy and ideally should not be installed close to homes, but there are many locations where it is still possible to site them without too many problems. Visually I rather like them, though it depends where they are.

Glyndebourne, for example, has installed a wind turbine up the road which is intended to supply most of its electrical power needs.

I doubt that PV is as bad as claimed re greenness. A panel should last for 25 years, and I think that the equivalent energy used in its manufacture is generated within 2-4 years, though I'm really not sure..It may be better than that. In any case these have to be greener than most devices, which require energy to make, and require energy to run. Cars, for example.

PV is still marginal/doubtful economically., though there is a gradual shift in favour as panels become more efficient. Currently they are not viable economically without subsidies, and in the long term the Treasury is right to aim at reducing subsidies. If the subsidies on PV are reduced to zero there will still need to be FiTs or similar to reward generators for the electricity they generate, but not at rates higher than the cost of other forms of generation.

Solar heating units based on water heating are better than PVs. Some of the economic "problems" for such systems are because manufacurers produce units and sell them at relatively high prices. I believe that in the UK a typical domestic water solar system will cost £4-£5000, and without any form of subsidy the break even time could be 10-15 years. I know someone who has installed a water based heating system in Greece for much lower capital costs than that, and not using "third world" components either. It is possible to keep houses in the UK warm enough using this kind of technology, though not completely trivial. Again, I know people who have done this. If the solar generated energy is only used for hot water, then whether this is useful may depend on how many hot baths and showers you wish to take. I didn't mention the water consumption!

Using PV generated electricity for heating is pretty dumb, unless there is no other option. It would be better to use the electricity to power a heat pump system.

Hydro generation is good in countries which have large mountains. It's not a great option in the UK, though it does have a role in load balancing, as water can be pumped uphill when there is excess energy generated, and then allowed to flow down again for generation when demand is high.

Arguments based on efficiency have to be treated carefully, as many of our existing methods of generation and energy use are not efficient. They were even less efficient one or two hundred years ago. We are more concerned now than we were. It really depends what we want to do.

[ahinton]

Solar heating units based on water heating are better than PVs. Some of the economic "problems" for such systems are because manufacurers produce units and sell them at relatively high prices. I believe that in the UK a typical domestic water solar system will cost £4-£5000, and without any form of subsidy the break even time could be 10-15 years. I know someone who has installed a water based heating system in Greece for much lower capital costs than that, and not using "third world" components either. It is possible to keep houses in the UK warm enough using this kind of technology, though not completely trivial. Again, I know people who have done this. If the solar generated energy is only used for hot water, then whether this is useful may depend on how many hot baths and showers you wish to take. I didn't mention the water consumption!

That argment's all very well but, as with anything else, if the materials and installation price plumments, your argument (which I don't currently endorse) could well become sound.

Using PV generated electricity for heating is pretty dumb, unless there is no other option. It would be better to use the electricity to power a heat pump system.

No; heat pumps - air source and ground source - useful devices that they can be, are expensive to purchase and install and require a lot of electricity to run!

[Resurrection Man]

On what basis do you seek to allege this?

In the link I gave.

[Resurrection Man]

..... Visually I rather like them, though it depends where they are.

Precisely so. Which makes it even more sense to put them offshore.

....

I doubt that PV is as bad as claimed re greenness. ....

On what basis can you justify this claim? Did you look at the link?

[Resurrection Man]

.....
No; heat pumps - air source and ground source - useful devices that they can be, are expensive to purchase and install and require a lot of electricity to run!

Which is where PVs come into their own. A near neighbour (an astro-physicist by trade) made a very exhaustive study of costs and benefits of all renewable sources and populated a very creditable and as far as I can see faultless spreadsheet. Groundsource heat pump/ PV array (a large one) won hands-down. Since he installed it, he has continually monitored it and the figures have exceeded his worst case scenario. So, no, in this case you are wrong.

[french frank]

Quote Originally Posted by Dave2002

I doubt that PV is as bad as claimed re greenness. ....

On what basis can you justify this claim? Did you look at the link?

Do you mean the Postnote?

It does classify PV as an 'emerging technology' and indicates that current research is focusing on the less energy efficient aspects.

"Using less raw materials would also lower life cycle CO2 emissions, especially in emerging technologies such as marine and PV. New semi-conducting materials (organic cells and nano-rods), are being researched for PV as alternatives to energy and resource intensive silicon."

[An_Inspector_Calls]

Is Alpine getting at me for using the word 'foolish'? If so, then the imagined insult is a tad precious.

Ahinton/Dave2002
If you're about to embark on the schemes you've outlined (Ahinton into French solar PV, Dave2002 into solar thermal) then do make sure you do a proper financial assessment, Don't fall into the trap (like many have done over the solar PV scam) of taking the annual income, dividing it by the capital expenditure and then declaring that 'I'm making an 8 % return on my PV system'. You're not: you've forgotten that you've no longer got your capital in the bank.

Ahinton: I used the 'foolish' example of heating domestic water from on-peak electricity as a 'highest cost alternative' to solar thermal heating to paint solar thermal in the best financial light. It looks as if, even on that basis the straight payback period is over 20 years, not the 10-15 years Dave2002 claims. If you factor in discounted cash flow (if you will, an alternative to accounting for your lost investment interest on your sunk capital) the payback periods are much longer; indeed, perhaps never. Now consider that any fool (sorry Alpine) in that situation would see that their on-peak electricity bill was too high, and as an alternative, switch to off peak electricity - halving their domestic hot water costs, and pulling the domestic solar payback to nearly 40 years!

Your French PV example is worrying. You're proposing to invest on the basis that the French government pays solar PV operators handsomely for the electricity they export. Do you expect that to continue forever?

The only domestic renewable energy production system that ticks all the economic boxes seems to me to be water or air source heat pumps - widely used in Japan, Scandinavia and New Zealand.