Going Solar PV

dan_b

A2OC Donor
Well today I signed the order for a 2.2kw solar PV system to go on my south-facing roof, with an Immersun "export energy immersion heater controller" device to harvest all the excess electricity generated over house base load as power into the electric hot water immersion heater.

Gas and electric prices aren't going to stop going up are they, and with a power-hungry family, I thought I might as well do see how I can reduce my bills - generate it myself!

Looking forward to the install, will take pictures of course. The inverter I've specced has got an online monitoring and logging facility which is fun - you can even monitor the power outputs of each individual panel.
 
Have you looked at the recent "Which" issues? They seem to be indicating that you cannot achieve a return of 4% now on your investment? I feel that I "missed the boat" with the far more attractive feed-in rates that were initially offered. Am I wrong?

David
 
Don't believe anything Which? has to say!

Put it this way, when the FITs were introduced, installation costs were more than 3x what they are now, so even though the FIT has been reduced, the actual cost of acquiring the kit has come down significantly more so. The ROI calculations I've done on the system I've just commissioned is in the order of 10-12% and the pay-back time for my rig, assuming electricity and gas prices don't increase (which they will) is under 5 years. The equipment is cheaper, the power outputs are higher, the installation rates are lower, and clever new British stuff like the Immersun means you can actually use all the power you generate (and you still get paid as if you're exporting it to the grid!).

I'll let you know how I get on!
 
sounds great.
I had two prices for panels,one lot were Canadian solar who really use Chinese panels around £5k installed for a 4k split array.
better panels were 6.2k for a 3.5 setup
 
Well, an awful lot of people do believe "Which", and subscribe. I have realised that there must be a lot of Companies that had hoped for "boom times", and who now have little business and (probably) a stock of panels. I thought that I would have the ability to install these panels myself (I have designed and partly built this house, anyway!), so that might have been worth doing. The rear roof area is South-facing, over 25 metres long and with a substantial height .... an enormous potential area for solar panels! I already have solar heating for hot-water, and that is highly effective. The only sad thing in my opinion is the drop in feed-in tariff from 45p/KW > 25p/KW > 19p/KW A not so attractive return on your investment? Hey, it's good to see the forum lending itself to something other that the A2! LOL!

David
 
Hi David
If you self-install, you'll not be eligible for FiT anyway unless you're MCS-certified. Similarly with solar hot water - next year the Govt will launch the "renewable heat incentive" scheme which is essentially a FiT for solar hot water, but again to qualify the system has to be certified.

The point of the drop in the FiT is that it is reduced in relation to the cost of the system installs, and also the take-up of the scheme. It is now reviewed every 3 months depending on how many systems are installed in the preceeding 3 months.

2 years ago when the FiT was 45p I got several quotes for Solar PV and at that time the install quotes were all north of £12k. Payback time then was going to be over 10 years. Now, 2 years later, my system is costing 1/3 of that, will generate more electricity as the panels are more powerful, and the payback time is much shorter. The raw numbers of the FiT subsidy is only part of the decision...
 
Interesting thread...is there a good website that explains solar panels/energy for the home (Googling comes up with thousands of sites).....for us Numptys who dont really know what we are looking at?

I like the idea of having renewable energy...but do not know the first thing about it and want to research a bit before some company takes me for a ride.

Thanks
 
Dan,
Well, thank you for all that very useful information! You seem to always make such sensible and reasoned decisions! Therefore, I feel that I wouldn't do better than to just follow your route! So, of great interest to me is the name of the Company/system that you've gone for and your total Capital outlay? (Maybe that will give you an extra bonus if you end up introducing further Customers?)

David
 
Hi David

I do believe in the adage "spend in haste, repent at leisure", and the whole Solar PV thing is a total minefield - there are so many competing installers and technologies!

Happy to provide you more info - probably best if I wait until my system is installed though before I can wholeheartedly recommend the supplier I've chosen, or not?!

I have gone for a "SolarEdge" based system which has an individual power optimiser tied to each panel in order to maximise the generation output from the restricted space I have on my roof and also to try and mitigate a potential shading issue from a chimney stack on the West side of my roof. Shading is highly complex and dealing with its impact effectively is the real sign of a well-engineered system. The monitoring software will be interesting I'm sure!
 
Well done Dan, keep us posted! My roof is West facing with the end of terrace wall of my house facing south, I have thought about these with the prices falling. However, I have a young, A rated combi boiler with no tank. So I'm really going to rely on selling to the grid to get ROI or a big expense to chuck away the good combi and get Solar heated tank setup.

However, I like that Immersun stuff. It sounds similar to my next project (time permitting) which is essentially around the idea to maximise day time generation. I'd use smaller panels to charge car batteries during the day, then feed 12/24V DC, no inverter needed, to a different circuit in the house. This then directly drive LED lights built to take only DC supply as well as minimising resistor burn by custom arrangements of the LEDs. Then I get free lighting at night plus long life of LEDs.
 
I certainly will!

I was giving serious consideration to "just" installing solar hot water, but it was getting more and more complicated with my frankenstein-like home plumbing - I have a pretty recent (less than 5 years old) mains pressure hot water cylinder and although you can retrofit solar coils into these, it does come with some risk, and then thinking about things like plumbing in some sort of heat-dump (for situations like when in mid-summer when the solar heating is at it's highest but you go away for 2 weeks so no hot water is drained off, so you end up with a boiled over hot water tank if you don't dump the heat somewhere!), it was getting to be quite an expensive solar hot water system (also to try and accommodate the forthcoming solar heat incentive payments it would have to be MCE certified rather than a DIY job), and then I discovered the Immersun product. British designed and built, and an elegant way of harvesting the excess electricity and requiring no physical or plumbing changes to that expensive pressurised hot water cylinder...

I've replaced almost all of my 50w halogen spotlights now with LEDs, and recently had a load of new double glazing installed, so doing my bit to reduce my energy consumption. Let's see how the solar PV goes!

Your battery-storage with DC lighting system sounds interesting!
 
Forgive me for seeming to rain on your parade however a few thoughts! First of all I would guess the panels are made in China, 2) have they given you figures for how much the efficiency of the panels deteriorates over time? 3) what happens when a panel fails? Who pays for its replacement? 4) What happens if the electricity generation/output forecast is not met? 5) The subsidies are paid by everyone which puts already poor people who cannot afford such devices ever deeper into fuel poverty, now there's a moral dilema! I have no problem with the concept of PV's, solar water heating etc and have long supported the idea of any energy production which is intrinsically 'free', I just have a problem with subsidising it and especially by (hidden) surcharges on the bills of people who can ill afford to. If it is such fantastic tech it wouldn't need any subsidy and if it didn't come with a subsidy artificially inflating the price paid would anyone be installing PV's?
 
1. Hyundai panels so not made in China. The British made panels are too expensive too large and not powerful enough.
2.yes they give decay rates for performance over time.
3. They are warrantied for 12 years.
4. Then my payback time is longer. I'm not doing this solely for ROI so no worries.
5. The question should be why do we continue to subsidize the oil and gas industries so heavily in tax breaks and government backed insurance to maintain the status quo? Why do we continue to permit such wasteful housing designs and building techniques to be allowed? The net cost of the FIT subsidies to the average consumer is small.
 
I do know a little bit about housing design having run my own Architects practice in the past and now run a local authority housing programme. Addressing building design standards will make barely a pin prick of difference in energy consumption at UK level let alone world wide, king canute comes to mind with much of what we try and do HOWEVER i do agree any passive measures such as superinsulation which will reduce the occupiers/bill payers energy consumption and bills has to be worthwhile. i just personally do not agree with consumers being expected to pay the subsidies for others who are usually better paced financially (such as our PM's millionaire father-in-law who receives £300k a year in consumer funded (in other words you and me) subsidies for his windfarm) and have a big problem with any energy saving devices which are 'active' as that immediately imposes future replacement/repair costs on the landord or property owner. Most housing associations simply do not want PV's, ground source heat pumps and the likes due to the long-term and uncertain costs they will end up with. And I do not personally call £100 a year on the average domestic fuel bill (which is for all so-called 'green' subsidies) small....... The issue of tax breaks for oil production is a different issue altogether and cannot be compared with FIT or wind farm subsidies. However we all have our own views but I could not let this go unchallenged!
 
My head in the clouds dream would be to build a brand new house conforming to a PassivHaus type design somewhere my local area, but the cost of land (and availability) here is impossible!

I have to challenge the £100 a year figure for average domestic fuel bills claim though - it's simply not true by the way. This was clarified in a question to Parliament back in October 2011 as this figure has been bandied about a lot by the media.

The actual figure is that ALL of the UK Government's policies to increase development and uptake of renewable energy and increase energy efficiency since 2002 has cost the average consumer £100 over that 10-year period - and to clarify that figure includes subsidies for development of wind farms (on-shore and off-shore), subsidising the "free home insulation and CFL bulbs" programmes to make homes more efficient etc. The SolarPV FiT is one relatively small component of that and is reducing over time...
 
Hello Adrian/List

I do know a little bit about housing design having run my own Architects practice in the past and now run a local authority housing programme. Addressing building design standards will make barely a pin prick of difference in energy consumption at UK level let alone world wide, king canute comes to mind with much of what we try and do HOWEVER i do agree any passive measures such as superinsulation which will reduce the occupiers/bill payers energy consumption and bills has to be worthwhile.

OK & agreed mostly, Insulation is the cheapest & best way forward, but I have to disagree with your statement about building design, what about passivhaus standards??

i just personally do not agree with consumers being expected to pay the subsidies for others who are usually better paced financially (such as our PM's millionaire father-in-law who receives £300k a year in consumer funded (in other words you and me) subsidies for his windfarm)

He is doing something - he could do nothing, unless lots of people do something, then hurricanes like Sandy will become more & more frequent - forget the PM's millionaire father-in-law's subsidies, it majes no difference to the average person's electricity bill. If the ROI was so great, then everyone would have a windfarm.


I have a big problem with any energy saving devices which are 'active' as that immediately imposes future replacement/repair costs on the landord or property owner.

So what??

Most housing associations simply do not want PV's, ground source heat pumps and the likes due to the long-term and uncertain costs they will end up with.

Most housing associations do not want PV's, ground source heat pumps & the likes due to the fact that they are not responsible for the energy costs of the properties they own and rent out.


And I do not personally call £100 a year on the average domestic fuel bill (which is for all so-called 'green' subsidies) small.......

Neither do I - but bring it on - when I moved into my current house seven years ago my first years energy bill was over 3,600€. Since then I have installed lots of insulation and a solar thermal heating system which provides 100% of my DHW together with space heating for the house in Autumn Winter & Spring. In the summer, the excess energy is used firstly to heat a hot tub, then a 10M by 5M swimming pool when the hot tub is up to temperature

The system has cost in the region of £5k, it has been self installed - so no subsidy from anyone, but my energy bill for the last 12 months has been under 600€ - Has the price of electricity really dropped that much over the last 7 years????

The issue of tax breaks for oil production is a different issue altogether and cannot be compared with FIT or wind farm subsidies. However we all have our own views but I could not let this go unchallenged!

Indeed

GET1962
 
I certainly will!

I was giving serious consideration to "just" installing solar hot water, but it was getting more and more complicated with my frankenstein-like home plumbing - I have a pretty recent (less than 5 years old) mains pressure hot water cylinder and although you can retrofit solar coils into these, it does come with some risk, and then thinking about things like plumbing in some sort of heat-dump (for situations like when in mid-summer when the solar heating is at it's highest but you go away for 2 weeks so no hot water is drained off, so you end up with a boiled over hot water tank if you don't dump the heat somewhere!), it was getting to be quite an expensive solar hot water system (also to try and accommodate the forthcoming solar heat incentive payments it would have to be MCE certified rather than a DIY job), and then I discovered the Immersun product. British designed and built, and an elegant way of harvesting the excess electricity and requiring no physical or plumbing changes to that expensive pressurised hot water cylinder...

I've replaced almost all of my 50w halogen spotlights now with LEDs, and recently had a load of new double glazing installed, so doing my bit to reduce my energy consumption. Let's see how the solar PV goes!

Your battery-storage with DC lighting system sounds interesting!

Dan,

You could have a system like mine where you have two tanks, one primary, heated by solar and other means, and a secondary, heated by solar (only) when the solar-heated water is not hot enough to heat the primary (when other solar systems would be inactive). The secondary feeds the primary so water entering the latter is heated, not cold. So you could use your existing tank as the secondary. When the water in the primary tank gets above a selected value you can also switch solar heating to the secondary and not dump heat.

RAB
 
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