Free solar panel discussion

BrummyGit

Cardew wrote: »

Welcome to the forum.

There are literally thousands of posts on this subject in the 'Green' section of MSE that you may wish to read.

If you rent panels, the bottom line is you will do well to save £80 to £100 per year off your electricity bill.

I think there is scope for a more balanced view of the situation. Whilst in some circumstances you are no doubt correct, surely it depends on the consumption patterns of the household, plus the generation capacity of the Solar PV system?

A house where everyone is out at work all day and only really has a small fridge on, then everyone returns in an evening after dusk and starts cooking, showering and washing would surely not benefit by even this much. This might be a bachelor or young couple in a small home.

However a large system on a home with people who are typically in during the day, cook their main meal at lunchtime using electricity, wash clothes, shower and heat their water electrically mainly during the strongest daylight hours is an entirely different case. This could typically be pensioners or a family with young children where maybe both parents are home during the day.

For my case I usually work from home, and run my computer and TV when working, plus occasional kettle and coffee machine. I have the luxury to try to time the use of my high consumption appliances (washing machine, tumble dryer and dishwasher) to suit the profile of my PV system, including using them sequentially to control the total load. At weekends my 3 kids are frequently using their TV, laptop and games consoles during the day. I therefore expect to be one of the people who benefit more than average.

The background consumption of my home is around 350-400 watts (2 fridges, large freezer, TVs and other stuff on standby, a lizard in a heated vivarium). So a rough calculation tells me that this consumes 3500 kwh per year. Using another very rough calculation of 10p per unit that's £350 per year on my background consumption. If I manage to cover just a third of that (currently in early March I'm covering my background consumption from 8am through until 6pm) you can see that I stand to benefit more than £100 per year.

I also find the original 70% saving that was quoted difficult to accept, but I do think the is a place for less negativity and more objective answers.

Delerium_2

Very useful thread. In this day of credit crunch and recession I had some funds I wanted to invest but there was nothing really worthwhile out there.

This thread caught my eye and as of December, i had a nice array installed on my garage

I was enticed by the figures quoted by the installer. Obviously i know they're all based on weather averages and assumptions but still looks quite nice

If you've got any questions this thread doesnt cover on solar panels, gimme a pm - I've done/did a lot of research before shelling out

I've scanned in the quote from the installer which explains the expected returns and shows the weather averages etc (all looks quite professional!) - if you want to see it, pm me and ill send you a url to the image file.

James

furndire

Have a look on here Delerium, and maybe add your monthly output - its interesting to see how your panels are performing compared to others My figures are on there http://www.uksolarcasestudy.co.uk/ It is Nang an MSE member who runs the site.

Cardew

BrummyGit wrote: »

I think there is scope for a more balanced view of the situation. Whilst in some circumstances you are no doubt correct, surely it depends on the consumption patterns of the household, plus the generation capacity of the Solar PV system?

A house where everyone is out at work all day and only really has a small fridge on, then everyone returns in an evening after dusk and starts cooking, showering and washing would surely not benefit by even this much. This might be a bachelor or young couple in a small home.

However a large system on a home with people who are typically in during the day, cook their main meal at lunchtime using electricity, wash clothes, shower and heat their water electrically mainly during the strongest daylight hours is an entirely different case. This could typically be pensioners or a family with young children where maybe both parents are home during the day.

For my case I usually work from home, and run my computer and TV when working, plus occasional kettle and coffee machine. I have the luxury to try to time the use of my high consumption appliances (washing machine, tumble dryer and dishwasher) to suit the profile of my PV system, including using them sequentially to control the total load. At weekends my 3 kids are frequently using their TV, laptop and games consoles during the day. I therefore expect to be one of the people who benefit more than average.

The background consumption of my home is around 350-400 watts (2 fridges, large freezer, TVs and other stuff on standby, a lizard in a heated vivarium). So a rough calculation tells me that this consumes 3500 kwh per year. Using another very rough calculation of 10p per unit that's £350 per year on my background consumption. If I manage to cover just a third of that (currently in early March I'm covering my background consumption from 8am through until 6pm) you can see that I stand to benefit more than £100 per year.

I also find the original 70% saving that was quoted difficult to accept, but I do think the is a place for less negativity and more objective answers.

I don't see much conflict between what I have written i.e. "If you rent panels, the bottom line is you will do well to save £80 to £100 per year off your electricity bill." and your ambitions.

You say yourself that you expect to save more than average - well if you do you will have 'done well'! In any case many people are out at work and given the vagaries of British weather, it is not possible to set timers etc.

Read the reports in the 'green' forum of those posting their daily generation figures, some days they get nothing - next day 20kWh

There are people who have had their own systems for some years and have export meters so they can accurately measure what they consume in the house.

On MSE, one of these has wife and 2 small children at home all day and uses approx 500kWh PA, the other 1,000kWh pa.

That is also in line with other reports - including WHICH. A Shade Greener(ASG) in another thread do not dispute that £100 pa is a reasonable estimation with their 3.3kWp system.

The problem is that many people having 'invested' in a 'rent a roof' product want to believe it is more beneficial and post reports like 'last year I paid £xxx for my electricty bill this year only £yyy so my panels are saving me £zzz - hardly objective.

So I stand by my opinion that £80 to £100 annual savings will be good and is an objective assessment. If you believe your particular circumstances will enable you to save more - so be it.

Equaliser123

Gizmosmum wrote: »

Building control shouldn't be needed either most installers advise building control as part of the competent persons scheme.

Agreed. But my understanding is that building control still need to be advised - it is down to a question of who does it.

Gizmosmum_2

Equaliser123 wrote: »

Agreed. But my understanding is that building control still need to be advised - it is down to a question of who does it.

The trade body that the solar pv installer is registered with do it for standard installations anything more difficult is written into the contract with the customer that the customer will do it. The installers I've had contact with only do it if they have to and the MCS quote has a bit in that clearly says that planning permissiona nd building regs are the responsibility of the installer.

Nang

furndire wrote: »

Have a look on here Delerium, and maybe add your monthly output - its interesting to see how your panels are performing compared to others My figures are on there http://www.uksolarcasestudy.co.uk/ It is Nang an MSE member who runs the site.

I would be really interested in hearing from anyone who has their own pv setup with monthly figures that go back to last summer. Particuarly if they are based in the south or have an inverter other than an SMA Sunny boy. I am working on system performance comparisons.

If you do and are happy to have your figures published, please PM me, or contact me on the email address on the website.

Thanks Nang..

Delerium_2

furndire wrote: »

Have a look on here Delerium, and maybe add your monthly output - its interesting to see how your panels are performing compared to others My figures are on there <link> It is Nang an MSE member who runs the site.

ill definitley give it a whirl, the quote i got from the company was based on SAP 2009 figures and 3d modelling software to calculate any potential shading from structures (trees/houses etc). Would be nice to get another comparison tho - ill post back with the findings when i've read my metres

J

BrummyGit

Cardew wrote: »

I don't see much conflict between what I have written i.e. "If you rent panels, the bottom line is you will do well to save £80 to £100 per year off your electricity bill." and your ambitions.

You say yourself that you expect to save more than average - well if you do you will have 'done well'! In any case many people are out at work and given the vagaries of British weather, it is not possible to set timers etc.

Read the reports in the 'green' forum of those posting their daily generation figures, some days they get nothing - next day 20kWh

There are people who have had their own systems for some years and have export meters so they can accurately measure what they consume in the house.

On MSE, one of these has wife and 2 small children at home all day and uses approx 500kWh PA, the other 1,000kWh pa.

That is also in line with other reports - including WHICH. A Shade Greener(ASG) in another thread do not dispute that £100 pa is a reasonable estimation with their 3.3kWp system.

The problem is that many people having 'invested' in a 'rent a roof' product want to believe it is more beneficial and post reports like 'last year I paid £xxx for my electricty bill this year only £yyy so my panels are saving me £zzz - hardly objective.

So I stand by my opinion that £80 to £100 annual savings will be good and is an objective assessment. If you believe your particular circumstances will enable you to save more - so be it.

My point was essentially that there are so many variables to consider that I think it is irresponsible to tell anyone that they could make in the region of £80 to £100 savings - as you say - for some it may accurate, but it may be more or less depending on individual circumstances.

You give no indication of the size of system for which your figures are valid, and indeed your wording "If you rent panels, the bottom line is you will do well to save £80 to £100 per year off your electricity bill." points to them only being valid for rent-a-roof. Surely the electricity savings are the same no matter what method of finance is chosen as the physical systems are the same. It's the FiTs and financing options that change the returns, but again I feel that if we are happy to list all the negatives of rent-a-roof, we should always point out the additional risks with other finance options (eg changes in interest rates, retrospective changes to the FiT scheme, maintenance costs, insurance costs, loss of access to savings etc).

Then of course there are the fees some people have agreed to pay - so from my rent-a-roof supplier I have a 3.52 kwp system which costs me nothing each month, but others with the same company have 2.4 or 2.6 kwp systems costing them a monthly fee. This totally changes the calculations once again.

Many on here give the Solar companies a hard time for unsubstantiated claims, therefore we really ought to make sure we give the clear message that there is no simple calculation which suits everyone. I am not trying to say that my circumstances are more valid for other people - everyone must analyse their own circumstances to see what works for them.

Delerium_2

BrummyGit wrote: »

My point was essentially that there are so many variables to consider that I think it is irresponsible to tell anyone that they could make in the region of £80 to £100 savings - as you say - for some it may accurate, but it may be more or less depending on individual circumstances.

Brummy's exactly right. With my array, im looking at an estimated profit of £31,000 over 25 years. But the generation i have is on a perfect 30 degree array south facing with no shading. And all the figures are estimates based on weather. (Before anyone says 31k is not achievable, if you take into account inflation, price rises and reinvesting income from FITS, it perfectly is)

So in summary, yeah its all down to individual circumstances. For me, its a very beneficial investment due to my location, and circumstances. For the next guy, it might not be by a long shot.

My advice is just get a survey from one or two suppliers and see what they have to say and run it by a few people here to see if its sounding reasonable (we arent qualified experts but we should be able to spot if someones taking you for a ride).

Del