Penners
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Never mind the food menu - he's going to build his own micro-brewery. Far more important!
- Thread starter Nigel Watts
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bower1
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I have a flat plate solar panel, which was installed in 2004 (not by me). I am yet to be convinced by it! It is however installed in a south facing wall, which means that it does not work at all well in the summer, the only time of year we need it (Rayburn runs hot water). It does work quite well in the winter, maybe getting the tank to 40 degrees, which I'm not sure it would if on the roof.
I am now considering moving it onto a roof (west facing) because it may at least do something then.
This is just my experience, and I'm not completely against solar water heating, it just seems that if not installed properly, its a very expensive piece of plastic.
I am now considering moving it onto a roof (west facing) because it may at least do something then.
This is just my experience, and I'm not completely against solar water heating, it just seems that if not installed properly, its a very expensive piece of plastic.
Nemesis
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Hope the micro brewery keeps going, unlike our local one:
http://www.cannybevvy.co.uk/Breweries/Redburn/redburn.html
Very sad, it was wonderful beer.
Still, there are others, although a little further afield:
http://www.highhousefarmbrewery.co.uk/aboutus.asp
Beer chocolates? Beer ice cream?
[Open Image] [Hosted by PhotoGalaxy.com]
http://www.cannybevvy.co.uk/Breweries/Redburn/redburn.html
Very sad, it was wonderful beer.
Still, there are others, although a little further afield:
http://www.highhousefarmbrewery.co.uk/aboutus.asp
Beer chocolates? Beer ice cream?
[Open Image] [Hosted by PhotoGalaxy.com]
Going back around to Solar Photo Voltaic cells...
The Energy Bulletin report is really interesting in that it suggests the 'common knowledge' that solar PV can't repay it's embodied energy costs is based around a solar power station case study. So includes a complex building design, labour and tonnes of concrete. Given a domestic array piggybacking on an existing roof has much lower design and installation cost and almost no supporting structure costs then it starts to look more probable that it can 'pay back' it's embodied energy.
One thing that worried me is this line
"The systems are assumed to receive an irradiation of 1700 kWh/m2/yr and have a performance ratio of 0.75."
I don't know if that is a reasonable irradiation figure for Britain if it's based on an Australian figure it could be substantially higher than we will achieve? That said if they really have calculated a 4 year pay back on embodied costs then even if we get 1/2 that then the figure is still well within the provable lifetime of the major components.
To play devil's advocate The Green Building Bible (Vol2, 3rd edition, page 51) quotes "For example 10m2 of PV cels would give a peak output of 1 kilowatt. This array would produce appoximately 700kWh of electricity each year. If electricity for a house can be purchased from the grid at 11p per kWh then the value of this electricity is £77 per year. The captial cost of the PV array is aprox. £600 for domestic buildings per m2. If we assume £6000 for our 10m2 this results in a simple payback period of 78 years!" - hmmm.
I have a fundamental issue with renewable energy 'paying for itself'. While I appreciate we're not all minted, I believe it's worth remembering that a coal, gas or oil burning power station is only ever going to be a net producer of CO2 - it will never 'pay back' anything even if it costs less financially. The reserves of oil, gas and coal are running out so if you can reduce your consumption and offset your usage by micro generation then all to the good. It looks probable you'll be paying more than the grid cost for now, but in the future that balance may shift.
It's worth noting that adding solar water and PV is often quoted by the manufactures as increasing the value of a new build, so it may be an 'investment' worth considering anyway. Of course if you stump £8000 for a solar PV system and quickly sell to someone who doesn't value it then you've prepayed their electricity bill for nothing. I do have trouble with how this kind of 'value' is worked though and by definition a period house is pretty unique which probably affects the balance.
I personally regard the current experiments with micro generation as a self funded field trial. If you have the money and will to take part then you can contribute to the process of discovering which technologies are suitable and stimulate demand to improve efficiency and product development. Even the infamous B&Q wind turbines are going to contribute to the overall knowledge base of what does and doesn't work in the UK.
Generating your own power is likely to affect your consumption based on a lot of case studies I've read. Watching your generation and consumption tick round makes you accutely aware of waste. Certainly moving from mains gas central heating to prepaid oil fired has changed how I use the central heating so I can see how it would work. Such a pity I couldn't find a water mill to buy
Solar water heating seems to be proven with the choice of competing technologies being the big obstacle for a home owner to overcome.
Solar PV seems to be a lot less proven but if you are able to make the capital investment it seems unlikely you will lose on the deal financially in the long term and it will lower your carbon footprint.
Case study from a manufacturer of solar PV roof tiles.
http://www.solarcentury.com/projects/domestic/the_merrill_family
The Energy Bulletin report is really interesting in that it suggests the 'common knowledge' that solar PV can't repay it's embodied energy costs is based around a solar power station case study. So includes a complex building design, labour and tonnes of concrete. Given a domestic array piggybacking on an existing roof has much lower design and installation cost and almost no supporting structure costs then it starts to look more probable that it can 'pay back' it's embodied energy.
One thing that worried me is this line
"The systems are assumed to receive an irradiation of 1700 kWh/m2/yr and have a performance ratio of 0.75."
I don't know if that is a reasonable irradiation figure for Britain if it's based on an Australian figure it could be substantially higher than we will achieve? That said if they really have calculated a 4 year pay back on embodied costs then even if we get 1/2 that then the figure is still well within the provable lifetime of the major components.
To play devil's advocate The Green Building Bible (Vol2, 3rd edition, page 51) quotes "For example 10m2 of PV cels would give a peak output of 1 kilowatt. This array would produce appoximately 700kWh of electricity each year. If electricity for a house can be purchased from the grid at 11p per kWh then the value of this electricity is £77 per year. The captial cost of the PV array is aprox. £600 for domestic buildings per m2. If we assume £6000 for our 10m2 this results in a simple payback period of 78 years!" - hmmm.
I have a fundamental issue with renewable energy 'paying for itself'. While I appreciate we're not all minted, I believe it's worth remembering that a coal, gas or oil burning power station is only ever going to be a net producer of CO2 - it will never 'pay back' anything even if it costs less financially. The reserves of oil, gas and coal are running out so if you can reduce your consumption and offset your usage by micro generation then all to the good. It looks probable you'll be paying more than the grid cost for now, but in the future that balance may shift.
It's worth noting that adding solar water and PV is often quoted by the manufactures as increasing the value of a new build, so it may be an 'investment' worth considering anyway. Of course if you stump £8000 for a solar PV system and quickly sell to someone who doesn't value it then you've prepayed their electricity bill for nothing. I do have trouble with how this kind of 'value' is worked though and by definition a period house is pretty unique which probably affects the balance.
I personally regard the current experiments with micro generation as a self funded field trial. If you have the money and will to take part then you can contribute to the process of discovering which technologies are suitable and stimulate demand to improve efficiency and product development. Even the infamous B&Q wind turbines are going to contribute to the overall knowledge base of what does and doesn't work in the UK.
Generating your own power is likely to affect your consumption based on a lot of case studies I've read. Watching your generation and consumption tick round makes you accutely aware of waste. Certainly moving from mains gas central heating to prepaid oil fired has changed how I use the central heating so I can see how it would work. Such a pity I couldn't find a water mill to buy
Solar water heating seems to be proven with the choice of competing technologies being the big obstacle for a home owner to overcome.
Solar PV seems to be a lot less proven but if you are able to make the capital investment it seems unlikely you will lose on the deal financially in the long term and it will lower your carbon footprint.
Case study from a manufacturer of solar PV roof tiles.
http://www.solarcentury.com/projects/domestic/the_merrill_family
biffvernon
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I wonder what the 'pay back' time of new kitchens and home cinema systems is? People seem to buy them with gay abandon
Nemesis
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I don't have either - am I missing something?
I prefer to spend my cash on beer...
I prefer to spend my cash on beer...
This article made me shelve any plans for solar power at the moment:
http://www.telegraph.co.uk/money/main.jhtml?xml=/money/2007/02/19/ccview19.xml
Also, this was too boring for me to read, but it could contain some hard facts.:
http://www.solarbuzz.com/Moduleprices.htm
http://www.telegraph.co.uk/money/main.jhtml?xml=/money/2007/02/19/ccview19.xml
Also, this was too boring for me to read, but it could contain some hard facts.:
http://www.solarbuzz.com/Moduleprices.htm
Nigel Watts
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Interesting article. There are several reasons why one might want to install solar panels for water heating or electricty generation. Saving costs is only one of them. Doing the right thing is another (or perhaps in the case of some politicians, being seen to do the right thing).
Penners
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I never realised that gender re-orientation was a factor in that market.biffvernon said:
plumbers mate
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Nemesis hopes that the micro brewery keeps going, unlike our local one:
If you are in North Wales there's some good ones -
eg http://www.purplemoose.co.uk/
lovely stuff - all of it ;-)
If you are in North Wales there's some good ones -
eg http://www.purplemoose.co.uk/
lovely stuff - all of it ;-)
Biff:
> No. Energy payback for pv is a very few years and
> getting better. This is, I think, a pretty reliable
> source:
> Energy Bulletin
I couldnt get a single byte from it, despite reattempts. Not so reliable.
Knowing your views to some extent, I know what to expect, and fully I expect the same old false methods were used to calculate embodied energy. These are the method used to ensure the suggestions produced by a whole army of jobsworths are taken seriously, and thus keep many people in employment.
The best way to know about PV payback is not to read what someone else thinks, and to see there are some with financial interests that agree with them. (What value is that?) Rather its to understand embodied energy:
http://www.greendoug.com/viewtopic.php?t=2
http://www.greendoug.com/viewtopic.php?t=7
understand PV systems:
news:alt.solar.photovoltaic
then either calculate it oneself or follow through many other peoples calcs for real systems.
The problem with your approach is that youre treating politics as science, when it isnt.
Doing it properly always produces the same conclusion: PV systems are a dead loss unless they avoid very high grid connection charges. By very high I mean £10,000 and up, which are costs remote properties can be faced with. For the rest of us theyre a total non-starter.
NT
> No. Energy payback for pv is a very few years and
> getting better. This is, I think, a pretty reliable
> source:
> Energy Bulletin
I couldnt get a single byte from it, despite reattempts. Not so reliable.
Knowing your views to some extent, I know what to expect, and fully I expect the same old false methods were used to calculate embodied energy. These are the method used to ensure the suggestions produced by a whole army of jobsworths are taken seriously, and thus keep many people in employment.
The best way to know about PV payback is not to read what someone else thinks, and to see there are some with financial interests that agree with them. (What value is that?) Rather its to understand embodied energy:
http://www.greendoug.com/viewtopic.php?t=2
http://www.greendoug.com/viewtopic.php?t=7
understand PV systems:
news:alt.solar.photovoltaic
then either calculate it oneself or follow through many other peoples calcs for real systems.
The problem with your approach is that youre treating politics as science, when it isnt.
Doing it properly always produces the same conclusion: PV systems are a dead loss unless they avoid very high grid connection charges. By very high I mean £10,000 and up, which are costs remote properties can be faced with. For the rest of us theyre a total non-starter.
NT
Biff:
> Pv technology is moving at a stunning pace
I'm surprised by this claim. What technological changes in real world pv systems have there been in the last 5 years?
In batteries?
In solar panels?
In invertors?
In topologies?
The very limited changes dont strike me as anything remotely approaching a stunning pace.
There is always research activity, but this is hope & dream stuff until it hits the market, and almost all research never makes it.
NT
> Pv technology is moving at a stunning pace
I'm surprised by this claim. What technological changes in real world pv systems have there been in the last 5 years?
In batteries?
In solar panels?
In invertors?
In topologies?
The very limited changes dont strike me as anything remotely approaching a stunning pace.
There is always research activity, but this is hope & dream stuff until it hits the market, and almost all research never makes it.
NT
bower1:
That I think is the biggest issue of all. So many SDHW systems never pay their way. Pro installed systems are especially problematic in this respect.
I think the way to work it out is to caculate rather than guess.
IRL theres interest to consider too, which will take payback time to over infinity. And the system lifetime to consider, which is a fraction of 78 years. Even in only 78 years such a system would get through numerous replacement parts. Over infinity years it would cost even more to keep going. So the cost figure being used in the above calc is way too optimistic on 2 counts.
> I have a fundamental issue with renewable energy
> 'paying for itself'. While I appreciate we're not all
> minted, I believe it's worth remembering that a coal,
> gas or oil burning power station is only ever going to
> be a net producer of CO2 - it will never 'pay back'
> anything even if it costs less financially.
Of course it does, thats why companies build them.
> The reserves of oil, gas and coal are running out
This popular myth appears to be based on a misunderstanding of the data. It costs a lot of money to explore, so only enough exploration for the near term future is done. Evidence does not indicate any shortage.
> so if you can reduce your consumption and offset your
> usage by micro generation then all to the good.
even if it takes more energy to get it going than it can ever generate?
> It looks probable you'll be paying more than the grid
> cost for now, but in the future that balance may shift.
Yes, energy costs can be expected to reduce over time, and the payback of existing ill conceived homegen schemes will look even worse.
Effective home gen is doable, with payback worth having, but too many schemes are just dead losses.
based on what the publicity dept says?? C'mon. Ask any estate agent, these systems add apx £0 to sale values.
Its a well known process, the mfr/seller thinks up a story they think some buyers will fall for, and tells people. Some buy into it, and purchase.
Sometimes reality doesnt match the dream. Especially when people are selling things.
NT
That I think is the biggest issue of all. So many SDHW systems never pay their way. Pro installed systems are especially problematic in this respect.
I think the way to work it out is to caculate rather than guess.
IRL theres interest to consider too, which will take payback time to over infinity. And the system lifetime to consider, which is a fraction of 78 years. Even in only 78 years such a system would get through numerous replacement parts. Over infinity years it would cost even more to keep going. So the cost figure being used in the above calc is way too optimistic on 2 counts.
> I have a fundamental issue with renewable energy
> 'paying for itself'. While I appreciate we're not all
> minted, I believe it's worth remembering that a coal,
> gas or oil burning power station is only ever going to
> be a net producer of CO2 - it will never 'pay back'
> anything even if it costs less financially.
Of course it does, thats why companies build them.
> The reserves of oil, gas and coal are running out
This popular myth appears to be based on a misunderstanding of the data. It costs a lot of money to explore, so only enough exploration for the near term future is done. Evidence does not indicate any shortage.
> so if you can reduce your consumption and offset your
> usage by micro generation then all to the good.
even if it takes more energy to get it going than it can ever generate?
> It looks probable you'll be paying more than the grid
> cost for now, but in the future that balance may shift.
Yes, energy costs can be expected to reduce over time, and the payback of existing ill conceived homegen schemes will look even worse.
Effective home gen is doable, with payback worth having, but too many schemes are just dead losses.
based on what the publicity dept says?? C'mon. Ask any estate agent, these systems add apx £0 to sale values.
Its a well known process, the mfr/seller thinks up a story they think some buyers will fall for, and tells people. Some buy into it, and purchase.
Sometimes reality doesnt match the dream. Especially when people are selling things.
NT
Absolutely. This is something of serious value to society. To do this one has to trial a new design not yet used, one with figures that look promising, monitor its output and performance, and publish the results.
Its such a shame many think of this ideal and then install kit whose performance is already well known, thus contributing zero knowledge to the subject. And they neither monitor nor publish the results.
Still, its a good sales line I suppose.
> Even the infamous B&Q wind turbines are going to
> contribute to the overall knowledge base of what does
> and doesn't work in the UK.
The performance of such designs has been known for decades. No new knowledge is being generated by them.
NT
Why Payback is needed
> I wonder what the 'pay back' time of new kitchens and
> home cinema systems is? People seem to buy them with
> gay abandon
Their payback is enjoyment and convenience, and nothing else, because they are a facility not had before.
Self gen provides a facility one already has, namely heat or light, so they need to provide some other value to make it worthwhile.
NT
> I wonder what the 'pay back' time of new kitchens and
> home cinema systems is? People seem to buy them with
> gay abandon
Their payback is enjoyment and convenience, and nothing else, because they are a facility not had before.
Self gen provides a facility one already has, namely heat or light, so they need to provide some other value to make it worthwhile.
NT
biffvernon
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NT, the link is good but the Energy Bulletin website seems to be down at the moment - please try later, as they say.
The article was a review of various pieces of research.
The pace of technology I was referring to was, of course nothing to do with the mature technologies of batteries and inverters, but related to the cell and panel manufacturing. There are improvements in cell efficiency and in manufacturing efficiency as well as economies of scale as new larger plant comes on stream.
I doubt whether we will see much price reduction of systems in the next few years but EROEI is certainly on a downward path. Probably little point in delaying purchase till next year in the hope of a lower price.
The article was a review of various pieces of research.
The pace of technology I was referring to was, of course nothing to do with the mature technologies of batteries and inverters, but related to the cell and panel manufacturing. There are improvements in cell efficiency and in manufacturing efficiency as well as economies of scale as new larger plant comes on stream.
I doubt whether we will see much price reduction of systems in the next few years but EROEI is certainly on a downward path. Probably little point in delaying purchase till next year in the hope of a lower price.
bower1
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NT said:
Or using the same design in a different situation (e.g. location)?
I was trying to discuss what I've discovered as part of an ongoing personal research project - while I was at it take account of there being more than two sides to this debate. I'm quite offended by some of those posts both the tone and content is partronising and rude. I added my own caveats to some of the things I posted as I am sceptical of the benefits but thought them worth mentioning.
When I quoted "simple payback" not only am I quoting another source I'm not claiming even a basic cost of ownership calculation. As that quote highlights, the system won't pay for itself at current electricity prices. Something that supports your position.
Google has that article cached perhaps you would like to read it before condeming it?
http://216.239.59.104/search?q=cache:LCCeHjYghNIJ:www.energybulletin.net/17219.html+energybulletin.net+17219.html&hl=en&strip=1
I can only hope you're right and we have infinite supplies of oil, gas and coal and that the weather patterns of the planet aren't changing rapidly and we don't have to do anything at all to our patterns of energy consumption. It will be a whole lot rosier than the future I'm reaonably convinced is around the corner.
When I quoted "simple payback" not only am I quoting another source I'm not claiming even a basic cost of ownership calculation. As that quote highlights, the system won't pay for itself at current electricity prices. Something that supports your position.
Google has that article cached perhaps you would like to read it before condeming it?
http://216.239.59.104/search?q=cache:LCCeHjYghNIJ:www.energybulletin.net/17219.html+energybulletin.net+17219.html&hl=en&strip=1
I can only hope you're right and we have infinite supplies of oil, gas and coal and that the weather patterns of the planet aren't changing rapidly and we don't have to do anything at all to our patterns of energy consumption. It will be a whole lot rosier than the future I'm reaonably convinced is around the corner.
A lot of people are worried about global warming (quite rightly so) but the issue is to do the right thing about it - using science as a base rather than guessing which is what a lot of people seem to be doing.AMc said:
Putting PV cells / micro wind generation into a house is wrong and very non green IF the energy it generates is less than the energy used to produce it. The problem is finding sensible figures on either of these. A very rough and easy calculation is to compare the cost of the system with value of the electricity it generates. [cost of something is roughly proportional to the energy required to make it (oh no not that argument again)]. Unfortunately, "being green" has become a fad and people are installing inappropriate technologies thinking they are doing the right thing when in fact they are doing the opposite.
A good comparable example at the moment is the generation of ethanol from corn in the US at the moment. Most people (outside of the US) think this is non green idea as the amount of energy in the ethanol produced is roughly the same as the energy required to make it and the corn could be used for better things - like feeding people. (Ethanol from sugar beet on the other hand is a lot lot better)