solar panels, windturbines, energy efficient boilers and cavity wall insulation

ziggy2004

We are having work done to the house and are at the same time looking to make it more energy efficient so we are looking at solar panels, windturbines, energy efficient boilers and cavity wall insulation. Now I can seem to get information on most very easily but can't find a lot on windturbines. I found the ones at B&Q but they really do not gve me a lot to go on.

I am also looking for peoples personal experience with these and different ways to reduce the amount of energy we use

TIA Anne

Cardew

There are several threads on solar power and and wind turbines in the forum.

I would read them thoroughly as the arguments are well rehearsed.

I am firmly in one camp - that they are not money saving.

I think you will find there is a concensus that there is a huge amount of totally misleading information on the purported cost savings - e.g savings 'up to' £x is meaningless. It is a area full of cowboys who have jumped of the Green bandwaggon.

I think everyone agrees that the B & Q Windsave is a joke - and a bad joke at that.

IMO get them if you want to do your bit for the environment, but at current prices you will not save money.

almacmil

Cardew is wrong. His figures are correct but he makes some assumptions which aren’t borne out. Moving to a solar lifestyle will save you money.

Cardew has ridiculed such statements in the past, even to the extent of suggesting a solar user who claimed to be saving money was either lying or had her figures wrong. I think she was probably correct, but in his determination to have his figures proved right, Cardew loses sight of some practicalities.

In his defence, Cardew and his calculations have proved very useful to many on here particularly in showing the cowboys’ figures to be wildly inaccurate and he has said that solar and other applications are useful in certain circumstances but his opinion is based on figures and not practical use.

His figures are based on “like for like” use. This assumes hot water in the tap 24hrs a day. A solar lifestyle will not give you that and this is where the savings accrue. With a solar lifestyle, you don't just change the way your hot water is produced, but how you use it too. You are much more aware of how and when you use your hot water and adapt accordingly.

My system is a panel, thermal store and immersion heater. This means we always have hot water in the morning (via solar from the day before, topped up by immersion heater). For the rest of the day and evening we are dependant on usage (ie how much is left over from the morning) and solar panel heated water, unless we use the immersion boost when we need a lot quickly - showers after sport for example.

We (family of 5) are much more careful about hot water and it is now second nature to watch how we use it (not anal about it at all!). We wash up in a smaller bowl, we often boil half a kettle for washing up. We are even aware of how much water is drawn off before the hot water gets to the tap as an equivalent amount is left cooling in the pipes! Dishwasher and washing machine are cold feed to stop draw off too. It really isn't any more difficult to live this way.

This is obviously not the panel per se saving us money but how we use the panel and it’s product. But without the panel, we wouldn’t be aware of how we use our hot water. If you want continuous hot water, then Cardew is right – it’s probably not worth it (unless it’s a new build maybe).

We have a new build 2000sq ft bungalow, DHW from panel and immersion, underfloor heating via GSHP, around 20 50W downlighters (not very MSE I know) and three kids with all their kit and we only pay £124 per month electricity - no other fuel. My previous house (much smaller but much older so less well insulated) took about £95 in electricity and £80 in fuel oil to run.

I can’t comment on turbines (they were very expensive when we looked – the Proven System), but my GSHP (sometimes called geothermal) is excellent.

adr0ck

almacmil could you please tell us what GSHP you use and what solar panels and what hot water tank you use?

thanks

Cardew

almacmil wrote: »

Cardew is wrong. His figures are correct but he makes some assumptions which aren’t borne out. Moving to a solar lifestyle will save you money.

Cardew has ridiculed such statements in the past, even to the extent of suggesting a solar user who claimed to be saving money was either lying or had her figures wrong. I think she was probably correct, but in his determination to have his figures proved right, Cardew loses sight of some practicalities.

In his defence, Cardew and his calculations have proved very useful to many on here particularly in showing the cowboys’ figures to be wildly inaccurate and he has said that solar and other applications are useful in certain circumstances but his opinion is based on figures and not practical use.

His figures are based on “like for like” use. This assumes hot water in the tap 24hrs a day. A solar lifestyle will not give you that and this is where the savings accrue. With a solar lifestyle, you don't just change the way your hot water is produced, but how you use it too. You are much more aware of how and when you use your hot water and adapt accordingly.

My system is a panel, thermal store and immersion heater. This means we always have hot water in the morning (via solar from the day before, topped up by immersion heater). For the rest of the day and evening we are dependant on usage (ie how much is left over from the morning) and solar panel heated water, unless we use the immersion boost when we need a lot quickly - showers after sport for example.

We (family of 5) are much more careful about hot water and it is now second nature to watch how we use it (not anal about it at all!). We wash up in a smaller bowl, we often boil half a kettle for washing up. We are even aware of how much water is drawn off before the hot water gets to the tap as an equivalent amount is left cooling in the pipes! Dishwasher and washing machine are cold feed to stop draw off too. It really isn't any more difficult to live this way.

This is obviously not the panel per se saving us money but how we use the panel and it’s product. But without the panel, we wouldn’t be aware of how we use our hot water. If you want continuous hot water, then Cardew is right – it’s probably not worth it (unless it’s a new build maybe).

We have a new build 2000sq ft bungalow, DHW from panel and immersion, underfloor heating via GSHP, around 20 50W downlighters (not very MSE I know) and three kids with all their kit and we only pay £124 per month electricity - no other fuel. My previous house (much smaller but much older so less well insulated) took about £95 in electricity and £80 in fuel oil to run.

I can’t comment on turbines (they were very expensive when we looked – the Proven System), but my GSHP (sometimes called geothermal) is excellent.

I am not sure what to make of your post; Cardew’s figures are correct but Cardew is wrong!!

These arguments tend to become too technical so I will make some points and people can make up their own mind.

I find that many people who have ‘invested’ in solar are not realistic about the finances involved or fall back on the laudable ‘I am saving the world from global warming routine’. There seems to be a tendency to defend their decision to get solar at all costs.

I have no axe to grind, I have researched this subject for a long while and state my views on the financial aspects for people to take it or leave it.

The main failings of people when calculating savings on solar is to totally ignore the loss of interest on capital expenditure and assume that it will be maintenance free for life.

If you invest, say, £6,000 in a solar HW system you need to save £360 a year to cover the cost of borrowing at a low 6%(or loss of interest on capital). Any system that uses pumps and electronics will eventually breakdown/require maintenance.

All the government figures show that most people spend between £100 to £150 on Domestic Hot water per year. There have been government run trials of Solar HW systems that show they produce on average 1000kWh per year. If you have gas that is a saving of £25 a year. Some larger and more expensive systems will produce more HW – but bear in mind that the great majority of that is produced in the summer months.

So pick a figure for your savings £50? £100? per year; some knowledgeable people on this forum who have solar systems say £50 to £75pa if they haven’t got gas. Is it worth the outlay and loss of interest? – you decide.

The above is for solar Hot Water which given current technology and prices is the most effective form of solar energy.

Solar electricity generation is more expensive to install and is less cost effective – although some experts believe that this will become a better proposition in the years to come. Even so just a minor point – you will need to regularly clean the(roof mounted) panels of grime and bird droppings – not a job some people will want to undertake by clambering on their roof.

If we turn to almacmil’s posting above.
He/she has a Ground source Heat pump(GSHP). For those who are unaware, this extracts heat from the ground and for every unit of electricity used you can obtain a multiple of that in heat(3 to 4 times the input in ideal circumstances). As the water tends not to get really hot they are better suited to underfloor heating(as Almacmil’s) rather than radiators.

However they are very expensive to buy. I have seen figures as high as £20,000 to install to an existing house – perhaps almacmil might say how much his cost?

Lastly depending on which figures you read it would appear that the average household spends approx £900 a year on all electricity and heating fuel. For all that almacmil has an impressive, but costly, solar system with a GSHP he apparently spends £1,488 a year on electricity.(12x£124) about 60% more than average!!

So you make up your own mind if Cardew is wrong or not.

If I am wrong let’s have some figures(assumptions even) of savings.

almacmil

Cardew wrote: »

I am not sure what to make of your post; Cardew’s figures are correct but Cardew is wrong!!

Did you read my post and digest before replying? Because I explain the above.... . Your figures are correct if a "like for like" comparison is made - but one of my main tennets was that "like for like" is not valid if people use solar as I explained. As a "like for like" replacement for a boiler system it's probably difficult to justify on fiscal terms.

These arguments tend to become too technical so I will make some points and people can make up their own mind.

I find that many people who have ‘invested’ in solar are not realistic about the finances involved or fall back on the laudable ‘I am saving the world from global warming routine’. There seems to be a tendency to defend their decision to get solar at all costs.

I find your terrier-like determination to prove your opinion correct to be equally as naive.:D

I have no axe to grind, (:D ) I have researched this subject for a long while and state my views on the financial aspects for people to take it or leave it.

Research or justification of your opinion? Researched with blinkers on perhaps.:p

The main failings of people when calculating savings on solar is to totally ignore the loss of interest on capital expenditure and assume that it will be maintenance free for life.

The main failing of those who castigate those who have moved to a solar lifestyle is ignorance - you have completely ignored my experience and relied on your bias.:cool:

If you invest, say, £6,000 in a solar HW system you need to save £360 a year to cover the cost of borrowing at a low 6%(or loss of interest on capital).

That's a fatuous argument - my experience is with new build (stated in my original post) - loss of interest isn't taken into account on a standard system, so why on a solar? A retro fit is a completely different postition and one that is more difficult to justify

Any system that uses pumps and electronics will eventually breakdown/require maintenance.

Correct - ANY system...... including conventional :rolleyes:

All the government figures show that most people spend between £100 to £150 on Domestic Hot water per year. There have been government run trials of Solar HW systems that show they produce on average 1000kWh per year. If you have gas that is a saving of £25 a year. Some larger and more expensive systems will produce more HW – but bear in mind that the great majority of that is produced in the summer months.

Apples and pears comparison - did you really read my post.......?

So pick a figure for your savings £50? £100? per year; some knowledgeable people on this forum who have solar systems say £50 to £75pa if they haven’t got gas. Is it worth the outlay and loss of interest? – you decide.

The above is for solar Hot Water which given current technology and prices is the most effective form of solar energy.

Solar electricity generation is more expensive to install and is less cost effective – although some experts believe that this will become a better proposition in the years to come. Even so just a minor point – you will need to regularly clean the(roof mounted) panels of grime and bird droppings – not a job some people will want to undertake by clambering on their roof.

If we turn to almacmil’s posting above.
He/she has a Ground source Heat pump(GSHP). For those who are unaware, this extracts heat from the ground and for every unit of electricity used you can obtain a multiple of that in heat(3 to 4 times the input in ideal circumstances). As the water tends not to get really hot they are better suited to underfloor heating(as Almacmil’s) rather than radiators.

However they are very expensive to buy. I have seen figures as high as £20,000 to install to an existing house – perhaps almacmil might say how much his cost?


Expensive? Nope - mine cost little more than a conventional system. DIY fit from KENSA. My DHW and underfloor system cost £2.75 k more than the quote for a conventional gas DHW and heating system (once grants had come in - but also excluding the cost of bringing a gas line in. The underfloor piping/fitting was same price for both). Again, retro fit may well be more.

Lastly depending on which figures you read it would appear that the average household spends approx £900 a year on all electricity and heating fuel. For all that almacmil has an impressive, but costly <---you missed out "IMHO" here Cardew 'cos you don't know - your bias is showing again.....;) , solar system with a GSHP he apparently spends £1,488 a year on electricity.(12x£124) about 60% more than average!!


I don't get this point? ^ Why do that comparison? It's apples and pears - who said my house was average? I tried to show in my OP that the rest of the house is relatively inefficient vis a vis lights etc but I still pay substantially less than I was in my previous property.

My reply, overall, was to the OP which asked about experience of some of the "green" technologies. My specific "Cardew" point was about solar and how it has changed my use of hot water - I know we use substantially less hot water as we don't take for granted that it's there at the tap; that doesn't necessacarily mean that the house overall is cheaper than your "average" (whatever that is). This is an argument you have invented to justify your position on solar


So you make up your own mind if Cardew is wrong or not.

As I said, it's both! Your figures are right but your blinkered bias is wrong! You have no experience of the solar lifestyle; you belittled the lady who tried to say she was saving money from solar, you make inappropriate comparisons and base most of your argument on assumption.
If I am wrong let’s have some figures(assumptions even) of savings.

I would have no idea where to start on figures or guesses of - it's new house. I've already made a comparison with my previous house. I know we use less hot water - but not necessacerily less electricity overall.

The above is pretty much what I expected and doesn't really acknowledge my central point - it's a rehash of Cardew's previous arguments which I contend have little relevance other than to those who think replacing a boiler with a panel and continuing as before will save them money - it probably won't.

Those who do move to a more solar-based lifestyle will use less hot water. That's obvious after a moments thought. (If it's not there you can't use it!) If you use less hot water, you use less energy and guess what? You don't get as big a bill every quarter and that is called money saving.....

But to be fair, you could get the savings without installing a panel, 'cos it's more about changing how you use your hot water than how you produce.

AND my experience is new build not retro-fit. It makes sense (IMO) in new build, but not so much in retro-fit.

geordie_joe

almacmil wrote: »

We have a new build 2000sq ft bungalow, DHW from panel and immersion, underfloor heating via GSHP,

So you have no idea what you would be paying for electricity in that house if it didn't have DHW from panel and immersion, underfloor heating via GSHP. Therefore you have no idea of how much you are saving.

Comparing what you spent in one house with what you are now spending in another is pointless in this case, as we want to know how much the DHW from panel and immersion, underfloor heating via GSHP is saving you.

almacmil

geordie_joe wrote: »

So you have no idea what you would be paying for electricity in that house if it didn't have DHW from panel and immersion, underfloor heating via GSHP. Therefore you have no idea of how much you are saving.

Comparing what you spent in one house with what you are now spending in another is pointless in this case, as we want to know how much the DHW from panel and immersion, underfloor heating via GSHP is saving you.

That's the only comparison I can make.

I was paying X in that style of house; now I'm paying Y in this.....

There are no before and after figures - how can there be? It was a new build. I have no idea how much it is saving me in real terms but I know that our use of hot water has changed/reduced because of the panel. The amount isn't quantifiable.

Angua2

ziggy2004 wrote: »

We are having work done to the house and are at the same time looking to make it more energy efficient so we are looking at solar panels, windturbines, energy efficient boilers and cavity wall insulation. Now I can seem to get information on most very easily but can't find a lot on windturbines. I found the ones at B&Q but they really do not gve me a lot to go on.

I am also looking for peoples personal experience with these and different ways to reduce the amount of energy we use

TIA Anne

Hiya. I'm researching to support my son's school and their quest to install a wind turbine. Thought some of the links could help you:

http://www.greenphase.com/wind.html
http://www.energysavingtrust.org.uk/generate_your_own_energy/types_of_renewables/microwind
http://www.energysavingtrust.org.uk/generate_your_own_energy/grants_for_renewables
http://www.reuk.co.uk/wind.htm
http://www.homeinspectorsuk.co.uk/domestic-wind-turbine.htm
http://www.lowcarbonbuildings.org.uk/micro/wind/
http://www.renewable-energy-directory.co.uk/?source=google-wind
http://www.bettergeneration.co.uk/wind-turbines/small-wind-turbine-reviews.html
http://www.greenliving.co.uk/Articles/theeconomiccasef.html
http://www.foe-scotland.org.uk/nation/micropower_tech.html


Interesting blog:
http://www.bbc.co.uk/blogs/newsnight/2006/11/are_domestic_wind_turbines_an_ecocon.html

Hope this helps.

almacmil

adr0ck wrote: »

almacmil could you please tell us what GSHP you use and what solar panels and what hot water tank you use?

thanks

I've got a Kensa 10kW GSHP and a Solartwin panel with a Gledhills Torrent 230L thermal store.

HTH.

adr0ck

almacmil

the Kensa website states that their GSHP only works best with solid floors (actually advises not to use with suspended timber floors)

i take it your new home is a bungalow? - if not how do you heat the upstairs?

if these GSHP 's only work with underfloor heating (in a solid floor situation) does anyone have a solution for whats best to use with suspended timber floors in a two storey house

thanks