Solar Panels experiences?

Hi everyone, just after some advice regarding buying solar panels.

Looks like the roof will take around 4Kw worth. What would be a typical price for this sort of installation?
A few questions for people who already have some:
How much did it cost?
How long did they take to install?
What sort of panels or inverters where used?
Have you experienced any problems so far?

A bit of a long shot but can anyone recommend any decent companies in east midlands around Derby/Nottingham area?

Many thanks 🙂

Anything here of help?

http://singletrackworld.com/forum/topic/solar-power-can-you-please-explain-a-few-things

thanks Cougar, that looks helpful 🙂

bump

No more than £6k all installed.

2 to 3 days depending on access

I have got 2.75 kw on my roof. This is the 3rd year now and i am getting the old original tariff.
The panels are Sony but not sure on the rest of it without going up in my loft(can’t at the moment as i am off work with broken hip)
The cost then was £9000. I have had about £1100 pound a year so far and would do it again.

Noserduke996, any idea what physical size they are?

They’ll be approx 950mm x 1600 if they are Sony from 3 yrs ago.

3.99kw on my roof cost £7800 – old tariff – 26 months = £3500 plus around £250 a year saving on electricity.

I’m considering getting PV panels installed. Any suggestions on which brand of panels are best? Or recommendations for an installer in Oxford?

Thanks!

Smudger666, is that measurement per panel? What rating is one that big?

I traded in £7k worth of shares I earned in my corporate life that made £100 a year in dividends for £7k worth of solar panels that earned £450 in the first 7 months after installation. * excludes electricity bill saving

Seems like win win to me as long as you can spare the money.

That’s per panel and they all tend to be the same size – the rating depends on the age / quality of the panel – all that has happened in silicon panels over the last 3/4 years is that the individual cells have become a bit more efficient allowing more power per area – so a modern 240/250W panel is the same size as a 210 or 220 w from 3-4 yrs ago.

If you assume 1.5m^2 per panel, you’ll be about right. Panels will be 240 or 250W depending how loose your installer plays with the DNO connection rules. If he offers you bang on 4kW ask him if he will indemnify you against any DNO connection charges.

ah, cheers smudger666. So the house down the road with 6, is likely to be a 1.5kW (ish) installation. And thats at the bottom of the making sense financially range.

Out of interest, anything stopping me putting them on a single storey flat roof. Can they be inclined to the perfect angle? Do they ever get stolen in situations like that?

You can get frames to incline the panels but this obviously adds to the cost (plus you’ve got to fit the frames to the flat roof which you’d need to decide if you’re happy about).
If panels are too accessible I think they could become a target depending upon the location. I’m not sure but there may also be planning issues.

Solar is brilliant but to get the best from it you need to make a couple of extra changes. One of which is fitting a proportional immersion controller which basically takes surplus solar generation and send it to your immersion heater so yo get free hot water without importing power.
Below is the temperature inside our 210L Megaflo cylinder – the temperature hike is due to the this mornings sun hitting the solar panels and the solarimmersion doing it’s stuff and heating the water for free.  

It’s not a full 24hr graph as I made some changes to the app that monitors the temp yesterday and that started the graphing from scratch again.

24hchart

That temperature decrease is staggeringly linear. It suggests low water use and poor insulation of the tank. I added a few weeks to my 100% solar hot water season by wrapping the already insulated solar tank in 22 layer insulation normally used for walls.

Indeed no water had been drawn off the tank for about 48 hours – insulation is standard Megaflo stuff plus some pipe insulation.

urban hiker

yes you can but there are some rules – practical and planning to look at first.

1. planning – you WILL need planning permission as the panels are extending beyond the current roof line.

2. practical – if you raise the panels at an angle you create a ‘sail’ area with a far greater wind resistance than when they are mounted roof parallel (which has almost zero increased wind resistance) and this has to be taken into account when checking the roof structure – you will need mountings that either weigh the panels down (up to 30-40kg/panel and hence need a stronger roof) or hold the panels down ( requiring penetration of the roof covering and a stronger roof – domestic extensions tend not to have that great a load bearing capability)

you also need to be approx 1m from each edge – this reduces the area available for panels significantly, as well as leaving a 2-3m gap between rows to avoid overshading.

you can see that I’m not a fan of flat roofs/solar panels unless we are taking about a factory sized installation!

HTH

Nice one. Sort of rules out the flat roof for me. The normal inclined roof only has room for 6, maybe 8 panels, which is not great from a financial payback point of view. Add to that I don’t have stored hot water, starting to look like a non starter.

Hey smudger – if your roof faces the wrong way (East/west), is it generally speaking still worth the bother?

From what I’ve been able to calculate, I’d see approx 20-25% less return. However, I do work from home so could utilise day time leccy.

Thats pretty much the case Cpt slow – the shallower the pitch, the less the effect.

i’d recommend you put an energy meter on your incoming line (approx 30-40 quid) and see what effect you being at home makes. I work from home but the office only adds 400 watts to the load in summer, 1200W in winter when i put the heater on.

Work from home too. And you’re right, generally only adds a few hundred watts. But does mean you can put the washing machine etc on while its sunny!

We have an E/W 4Kw installation (slightly more on the W side than the E) and it works pretty well and there’s not a great deal of loss. In the later afternoon/evening when S facing panels would not be getting any sun the W facing panels are producing 1.5-2Kw – Makes using the power generated easier as kids are back from school.

We have another house with a S facing 3Kw system and today this one produced 17.47Kwh while the E/W system produced 18.25Kwh even though there was more cloud cover at the E/W system location. Links to live data below:
E/W facing 4Kw system
S facing 3Kw system

Ok, thx folks. Perhaps I’ll keep it on the list then

On prices, in Apr 2010 you could expect to pay £16,000 for 4kW. Now that is more like £5k-£6k.

Panel efficiency impacts on the size of a panel. As mentioned above, an older less efficient panel will be bigger than a more recent higher efficiency panel of the same rated power (kW). The more you pay the higher efficiency panel you get, i.e. you don’t need the most efficient panels if you have the space available.

Worth having a look at the new installer guidelines from MCS – your installer must follow these guidelines for their accreditation process:
New MSC PV installers guide

There are now some small domestic storage units available on the market. Not exactly a good investment yet, but they will be soon. We’re only talking 3 – 4 kWhr of storage capacity but enough to help with some supply-demand matching.

Also this is a new initiative form the BPVA. Might be worth consideration to find a decent local installer:

http://ratedsolarinstaller.com/

thanks for all the responses 🙂