The Great 'Get Paid To Generate Energy' Hunt

skelly01

I live in a detached house with a south facing roof. I am not poor by todays standards, but find the cost of installing a PV system still very prohibitive.
The government seems to keep changing the goalposts with regards to the grants and loans that are on offer. The grant has been removed for PV systems in Scotland and now you can only get a loan for £4000.00.How can this be any use when the systems are approx £15000 to install? Surely they should set the grants , loans etc and stick to them.
I think the government need to do more to make it more encouraging, I was going to install a system, but until it is more financially viable in terms of the support then I will sit it out and wait.
I have notice this company " A shade greener" on another thread offering free systems. I would jump at the chance if there were any similar companies in Scotland. I am not wanting to make money , I just want to be able to generate clean electricity and do my bit that way.

Dave_Fowler

simbag wrote: »

On a separate note, I'd like to ask those in the know about efficiency ratings.

I've seen some rated on both cell and module efficiency - what is the difference/more important?

Also, when comparing efficiency, how much difference does it make? Does the KWp already take into account the efficiency rating? Or does a panel with a rating of 20% convert 33% more energy than a panel with a rating of 15%, under exactly the same conditions?

This would obviously make an enormous difference to the payback time, but would also have to take into account the extra cost of better more efficient technology, hence reason for asking the question.

Answers gratefully received.

The KWp power rating of a panel is the expected output power from that panel. A more efficient panel would be smaller for the same kWp rating compared with the less efficient panel.

The panels are made up of many cells. The cells are connected together to make the panel module. The cells are not simply connected together in one long string. They are arranged in a series/parallel grid. But consider if one cell is under-performing (perhaps in a shadow caused by droppings from a passing bird), the efficiencies of the other cells could be reduced by this one poor cell. To overcome this, the cells are connected in groups with by-pass diodes to reduce the shading effect. But all these added components slightly reduce the overall efficiency of the module even when there is no actual shadowing occurring. Hence the module efficiency is likely to be lower than the measured cell efficiency.

There are several technologies for the production of the panel:- the main ones are poly-crystalline and mono-crystalline and others, I think, called amorphous panels. Reading the various specifications, whilst the poly-crystalline panels are more efficient, the mono-crystalline panels have a lower degradation rate over time. The latest mono-crystalline panels claim to be 93% efficient after 20 years. (Nothing like as much as the 1%/year reduction mentioned earlier in this thread).

Whilst these panels have efficiencies in ranges up to 20% or so, the newest technologies (not on the market yet) are around 40%-50% efficient. These new technologies would lead to much smaller panels - much lighter and taking up much less roof space.

As the new technologies come on-stream, the prices are likely to fall and hence the investment involved in buying the panels would drop. The government have considered this in the planned reduction in FITs income for installations completed in later years. Fortunately for those jumping in during the next two years, the FITs income is guaranteed to start at the 41.3p/kWh and then RPI linked. But buy a system in three years time, the commencing rate of the FITs will be 10% lower - but still index linked. From these figures you can assume that the government expect PV system prices to drop 10% in the next 3 years.

Further efficiency considerations will be the efficiency of the DC-AC converter. A properly matched inverter running close to its designed output power can be around 95% efficient, but run the same inverter on a dull day when the incoming DC power from the panel is reduced, the efficiency could be 80% or lower. Remember it is the power output from the inverter which is metered for FITs payments. There are other power losses in the cables connecting the panels to the inverter and the inverter into your electrical system - but these are usually quite small provided cable runs are short and the suitable cable is used.

Cardew

simbag wrote: »

Hi there,

I just wanted to add a few pennies worth here. I do see where you are coming from with your views on warrantee, and it is something you repeatedly mention in this and another thread I Have been following on the same subject. However, 2 years is the minimum, you will find other companies offering better quality components with a 5 year warrantee.

A second observation I'd like to make on the same point, is IF you were to buy a brand spanking new car for £50,000, how many years warrantee do they give you on average?... 3 maybe 5 years tops? And how long would you expect he car to actually run for?

This is obviously an extreme example, but I hope you see my point, just because the warrantee is shorter than the expected lifespan doesn't mean that the product is likely to fail.

Simon
(a potential solar PV owner/"investor")

I certainly do see your point.

However taking your car analogy, you would expect to pay out regularly for maintenance and renewal of parts and, depending on the car, it would generally be scrappage material after 10 to 15 years.

However the calculations for solar PV seem to ignore this aspect and the fact that at some time in the future you are going to have scrappage bolted to your roof.

It is a factor to be considered - no more -no less.

I do appreciate that I come across as a solar pessimist.(and I am a fierce critic of the the 'solar industry') However I have considered fitting PV and if installation prices reduce significantly in the future might well get it fitted.

If(as EST stated) the cost of panels in the USA are down to US$2,200kWp that means the cost for the panels themselves(by far the major cost of a system) for a 4kWp system will be under £6,000. So why not a 4kWp system for £10k in the future.

To my mind solar PV is viable when any money invested is returned to me by the savings I make(including lost interest) in 6 or 7 years and I start to be in pocket for the rest of the life of the system.

simbag

I do appreciate the points you make also, especially with regards certain companies within the industry, I had a quote from one for a 1.8Kwp system just short of £15,000! :eek: Not to mention there were quoting 2500kwh per year, instead of the industry quoted average of 850kwh per 1Kw installed. (1530kwh for 1.8Kw installed), only a difference of 1000 per year! Just a small amount of research managed to quash all of the statements made in the survey.

I must admit, some of what you have said has made me stop and think about this whole thing a bit harder. Also, the great info Dave Fowler gives above, has made me wonder whether to wait a bit longer. We only have a limited space to use for the installation, approx 20 sqm, and I want to put the max possible KWp I can afford. Therefore, I don't want to find in a couple of years prices have plummeted and efficiency has gone up. But then, does the fact the FITS will also go down counteract the initial saving??

I would like to direct anyone who liked the EST calculator, to another website I have found which allows you to play around with almost every variable possible. The only thing it doesn't give you is ability to do is assess the cost of loan. PM me if you want the link, as I can't post it yet!

Bungle1976

As per the earlier posts (see pages 1 & 2) here are my actual real world figures for the solar thermal system in my house, based upon 12 months.

Now I will start by saying Cardew is right, my figures for payback were wrong. See, I can admit my mistakes!

To start, the figures for heating a tank of water using my existing system. This is a 1970's era Baxi back boiler which serves to throw a lot of heat up the chimney and as a by product gently warms some water which then uses a gravity feed to transfer to the hot water tank. So before the tank starts to warm up all the pipework between the boiler and the tank needs to heat first to get the water to circulate. Oh yes and the tank was uninsulated (literally a copper cylinder in the airing cupboard) and had a very slight weep (which I bodged up, but the tank was basically end of life).

To heat a tank of water from cold takes approximately 3 hours, during which time the boiler uses 13.47KWH of gas (measurements taken using a tank thermostat and the gas meter). This costs approximately £1 in gas (prices taken at the time I worked this out some time ago).

In addition, running the pilot light works out at 24p per day, or £88 a year.

On average, I heat the tank of water once every other day (do the washing up, have a shower, run the washing machine etc).

Last year I literally turned the boiler off (including the pilot light) from April to September inclusive. I only relit it on three occaisions (I think we can ignore that £3!). So six months without needing the gas.

6 months is 182 days, so every other day is 91 tanks of water, or £91

In addition I saved £44 of pilot light gas.

So I saved £135 last year.

The install cost was in the region of £3500 (don't have the exact figure to hand).

But it isn't that simple, the install came with a new tank which I would have needed anyway, the average quote for a new tank, fitted, was £400 (I had some higher, some lower). So the solar par of the install was £3100 (ok, that is a simplification but good enough for these purposes).

Now, I have also assumed an increase in gas prices of 5% a year (I reckon that is conservative!). Admitedly, I have now allowed for how much I would have if I "invested" the money, as a higher rate taxpayer I get b***** all in interest with cash.

My spreadsheet shows payback at 14-15 years.

Now the alternative was to fit a proper modern condensing boiler, I was quoted about the same cost as the solar install (it is a major exercise, even the new Baxi condensing back boiler is no good as my chimney is unsuitable). British Gas told me the average life of the boiler is 15 years and the payback time would have been......14 years! That of course doesn't include the higher maintenance costs of a modern boiler, there is little to go wrong with my current Baxi backboiler, but a modern condensing one has a lot of electronic gubbins and the as the only place I could install it is my loft it would not have been a particularly good environment for it!

So payback for gas condensing boiler 14 years, payback for solar 15 years. After 15 years I have an end of life boiler or a still working solar install (the only moving part on the solar is the pump which is very cheap to change if it packs up).

Additional factors not included in the above:

1. I have modified my washing machine to use hot water ONLY for the initial fill after first discarding the "slug" of cold water in the pipe (cheap and easy mod using a scrap corridor timed light switch), so saving the electric that it would normally use to heat the water up. Anyone know how much that saves? I suppose I could run a load from cold and from hot and measure the difference.

2. Even though it does not provide ALL my hot water for the other six months, it does provide a useful pre-heat to the water in the tank, this is probably a significant gas saving but I have not evaluated it.

3. When my girlfriend moves in we WILL use more hot water

Bearing in mind the factors above, my original spreadsheet with payback of 9 years (it had a copy/paste error) may not be as far off the mark as it seemed. It might not have been as good a payback as I was thought, but I would still do it.

Of course if you already have an efficient condensing boiler and a non leaking insulated hot water tank you will need to do the figures yourself for your circumstances and it may not make as much sense.

aboard_epsilon

Yep those washing machines really get my goat up ..


A house holder can heat their water inexpensively with gas. (wood coal or anything that would burn in my case) .and the blinking thing fills up with cold water on every program but the boil wash.and heats it up from there with electricity.
Says in the instructions some crap about warming up water slowly from cold is more efficient way of washing clothes.....what a load of bull.

My last washer some 20 years back was superb .it was a Creda Microelectronic 1000.........it actually sensed the water temperature ......added more cold or hot on each and every program until the temp was exactly right..and if it detected that the temp had reached the right temperature quite quickly, it shortened the wash program.

When I went shopping for my present one .there wasn't a salesman in any store that knew what the features of a washing machine were, only its so called efficiency grade ..
I bought a high graded one ..and got a duffer as far as I'm concerned.. !!!
Zanussi 1250 jetsystem excel....yeah sure .sounds like its going to take off ...it didn't with me appliance of science..... they must be kidding !

I have to be there every time, to turn the cold off when its on the boil wash program .so it fills with hot and not hot and cold at the same time .

all the best.markj

Cardew

Bungle1976 wrote: »

As per the earlier posts (see pages 1 & 2) here are my actual real world figures for the solar thermal system in my house, based upon 12 months.

Now I will start by saying Cardew is right, my figures for payback were wrong. See, I can admit my mistakes!

To start, the figures for heating a tank of water using my existing system. This is a 1970's era Baxi back boiler which serves to throw a lot of heat up the chimney and as a by product gently warms some water which then uses a gravity feed to transfer to the hot water tank. So before the tank starts to warm up all the pipework between the boiler and the tank needs to heat first to get the water to circulate. Oh yes and the tank was uninsulated (literally a copper cylinder in the airing cupboard) and had a very slight weep (which I bodged up, but the tank was basically end of life).

To heat a tank of water from cold takes approximately 3 hours, during which time the boiler uses 13.47KWH of gas (measurements taken using a tank thermostat and the gas meter). This costs approximately £1 in gas (prices taken at the time I worked this out some time ago).

In addition, running the pilot light works out at 24p per day, or £88 a year.

On average, I heat the tank of water once every other day (do the washing up, have a shower, run the washing machine etc).

Last year I literally turned the boiler off (including the pilot light) from April to September inclusive. I only relit it on three occaisions (I think we can ignore that £3!). So six months without needing the gas.

6 months is 182 days, so every other day is 91 tanks of water, or £91

In addition I saved £44 of pilot light gas.

So I saved £135 last year.

The install cost was in the region of £3500 (don't have the exact figure to hand).

But it isn't that simple, the install came with a new tank which I would have needed anyway, the average quote for a new tank, fitted, was £400 (I had some higher, some lower). So the solar par of the install was £3100 (ok, that is a simplification but good enough for these purposes).

Now, I have also assumed an increase in gas prices of 5% a year (I reckon that is conservative!). Admitedly, I have now allowed for how much I would have if I "invested" the money, as a higher rate taxpayer I get b***** all in interest with cash.

My spreadsheet shows payback at 14-15 years.

Now the alternative was to fit a proper modern condensing boiler, I was quoted about the same cost as the solar install (it is a major exercise, even the new Baxi condensing back boiler is no good as my chimney is unsuitable). British Gas told me the average life of the boiler is 15 years and the payback time would have been......14 years! That of course doesn't include the higher maintenance costs of a modern boiler, there is little to go wrong with my current Baxi backboiler, but a modern condensing one has a lot of electronic gubbins and the as the only place I could install it is my loft it would not have been a particularly good environment for it!

So payback for gas condensing boiler 14 years, payback for solar 15 years. After 15 years I have an end of life boiler or a still working solar install (the only moving part on the solar is the pump which is very cheap to change if it packs up).

Additional factors not included in the above:

1. I have modified my washing machine to use hot water ONLY for the initial fill after first discarding the "slug" of cold water in the pipe (cheap and easy mod using a scrap corridor timed light switch), so saving the electric that it would normally use to heat the water up. Anyone know how much that saves? I suppose I could run a load from cold and from hot and measure the difference.

2. Even though it does not provide ALL my hot water for the other six months, it does provide a useful pre-heat to the water in the tank, this is probably a significant gas saving but I have not evaluated it.

3. When my girlfriend moves in we WILL use more hot water

Bearing in mind the factors above, my original spreadsheet with payback of 9 years (it had a copy/paste error) may not be as far off the mark as it seemed. It might not have been as good a payback as I was thought, but I would still do it.

Of course if you already have an efficient condensing boiler and a non leaking insulated hot water tank you will need to do the figures yourself for your circumstances and it may not make as much sense.

Thanks for your post.

Having conceded you were wrong. I might be accused of putting 'the boot in' if I make further points. However for people contemplating solar thermal they should be made.

1. Firstly you cannot attempt to justify solar thermal for everyne on the strength of your 1970's back boiler.

2. Secondly you cannot argue that 13.47kWh of gas costs approx £1. You presumably are taking the Tier 1 kWh price of gas. The average price of gas taking Tier1 and Tier 2prices is around 3p for a kWh so your 13.47kWh of gas will cost approx 40p not the £1 on which you base your calculations.

3. It matters not that your tank was uninsulated. If you waste heat from the water heated by gas, then you will waste heat from water heated by solar. You can't have it both ways!!!

4. What is the relevance of the cost of fitting a a new combi boiler? You will need one for CH and hot water in the winter.; and you seem to forget that a combi does not need a HW tank - insulated or not!;)

5. You have ignored the cost of running your pump on daytime electricity rates and powering the electronics

So even by your(unsupportable) figures you claim to have saved £135 last year, for the investment of £3,100.(allowing £400 for a hot water tank that a combi doesn't need;))

Now even allowing you are a higher rate taxpayer(as presumably is your wife?/children?) you have lost £90(£150 LESS 40%) in interest to gain £135( so £45 net) which pays off £3100 in about 60 years.

In the real world your solar panels, as do everyone elses, produce around 1,000kWh per year(most of it in the summer). That saves around £30 a year if you have gas.

I wouldn't 'invest' £500 to save £30 a year in anything bolted to my roof that would eventually require maintenance and will finish up a pile of junk.

Sorry!!

noncom_2

Energy_Saving_Trust wrote: »

Ar ha - thank you for you challenge. The difference with this is that if you didn't install the technology, you would be paying money away anyway! Instead of making a loan repayment every month, you would be paying an energy supplier - forever!

The whole point of this is that at the end of the month your cash position will be better.

For example (so all 'say' figures)- before the installation you had a energy bill of 'say' £50 a month. After, your bill could reduce by say £10 a month, your loan repayment may be (say) £50 a month, but then your income from FIT and export might be £76 per month. (So a 2kWp retro installation at £4.5 per W with a 25 year loan at 4.5%)

You final month end position without the installation and loan = -£50 = £50 down

Your final month end position with the installation and loan = -£40 - £50 +£76 = £14 down.

So with the loans and panels at the end of the month you have £36 more in you bank account! Result - happiness

The issue of using up your credit limit may now be the concern, but this is why we have a team working on convincing government and the financial industry to launch new green finance (energy mortgages) that are based on energy generation/land/property charge/fuel bill/council tax rather than your personal credit worthiness. Have a look at the PAYS section of our website and the videos it links to.

What do you think?

What do I think? Bring it on...... It's pretty clear that the FITs will, for someone with a good site, generate enough income through the Generation tariff, Export tariff and reduced electricity importing to pay off a loan at a sensible rate. Personally I think the 4.5% you suggest is on the low side. In the mortgage market, a 5-year Fixed rate from Nationwide, for example is currently around 6%, but nonetheless the FITs scheme might just outrun even a higher rate than that.

The problem at the moment is twofold: one, that if interest rates go up (and FITs certainly won't) then that small extra amount in the bank every month could become a small loss every month; two, that if I have to sell my house before the "payback" time, which could be anywhere between 10 and 20 years, I have to persuade agents / buyers that my house is worth thousands more than a similar one without panels because of the revenue generated by the panels. Whether this will happen is not known, so I have to take on that risk.

Your scheme seems to address one of these issues, if I understand correctly. I think you are proposing that the "green loan" belongs not to the person who took it out, but to the house itself, so if I move house, then the person who buys it will now be responsible for paying it back, so removing the need to bump up the house price. (Of course, the buyer will have to be credit worthy for that extra debt, so effectively it is like adding thousands to their mortgage anyway).

The other issue is the one of interest rates. Are you proposing that long term fixed rate loans will be offered, guaranteed to keep the repayments below the FIT income? If so, who is going to subsidise these below-market-rate loans? The Government won't want to, I imagine, since it's going to be broke for the forseeable future whoever wins the election; and the energy companies won't, since they're having to pay the Tariffs (or rather their consumers are); as for the Finance industry, I wouldn't trust them as far as I could throw most of them.

So, it sounds like a great idea, which would turn a reasonable punt for those brave and well-off enough to risk it into a no-brainer for almost anyone with a good site. But is it really going to work in practice? I look forward to more explanation to see how it might do. And if you could drop one of these loans my way before I invest my own money in the PV system, then that'd be lovely! (I assume also that I won't be able to apply for one of these Green loans retrospectively for an already installed system......?)

Thanks
Andy

edenusk

There is a way of overcoming the initial high cost of a solar PV system and that is by leasing one. There are one or two companies now doing this and it seems to stack up extremely well.



Second point around the capital cost is, where are the much trumpeted low/nil interest capital loans? Currently the biggest single blocker to uptake is the prohibitive initial capital outlay, irrespective of the actual return available; This is where the real uptake will come from, by being clever in offering complete financed packages, at realistic capital costs only then will the massive uptake begin; What will follow could then be the much desired tens/hundreds of thousands of jobs directly linked to renewables. Crikey if we can bail out the banks as we have, just think what £50-100 million to provide subsidised loans would generate!!!
If Government or the traditional finance sector aren't interested, come on you green entrepreneurs & philanthrapists!



Big fan of renewables but thwarted beyond belief!

Jondaro[/QUOTE]

simbag

noncom wrote: »

The other issue is the one of interest rates. Are you proposing that long term fixed rate loans will be offered, guaranteed to keep the repayments below the FIT income? If so, who is going to subsidise these below-market-rate loans? The Government won't want to, I imagine, since it's going to be broke for the forseeable future whoever wins the election; and the energy companies won't, since they're having to pay the Tariffs (or rather their consumers are); as for the Finance industry, I wouldn't trust them as far as I could throw most of them.

I was under the impression that the FITS were paid through the energy companies, but funded by the government? Obviously they pay the export tariff though.