QOTW: Have you considered adding solar panels to your home?

[ReprovedRabbit]

No point when living in Ireland, we only get 3 days of sunshine a year.

You would be surprised with the performance of pv and other systems. I come from a building science/construction background in New Zealand and can tell you that doesn't matter. daylight does not require direct sun.

[=assassin=]

As has been already said by some, payback time is over many many years, so it isn't worth the initial cost. It would be good maybe if solar panels were provided on new homes, but it would still be reflected in the cost of the property; nothing is done for free.

[GuidoLS]

I've considered adding *more* panels, but that would force me to have to add more house as well, and that's not worth it overall.

I got in on the solar 'craze' years ago, before it was semi-mainstream. I've had to replace a few poorly made cells, but even paying out of pocket, after 20 years or so, I'm well ahead of the game. I'm at right about 70% off the electric grid - the only thing I pay for is refrigeration and cooling. I've been generating my own heat for as long as I've owned the house, but I'm now burning far less wood for heat because of solar heated polyglycol (or whatever the syrup is in the piping) and make all my own hot water as well via solar.

[jonah]

We were considering until the government slashed the tariff.

[tonyd223]

Yes - and doing the borehole heating thing

[daddacool]

Got as far as passing a site inspection to have them installed, then got cold feet. Basically the scheme I looked at saw me leasing the space above my roof for 25 years, with any "sold back to the grid" money going to the company that were installing the panels for free. I assume they were getting gov incentives at the time to install them.

I'd looked at this route because every other scheme that saw you pay up front for the panels had a repay period that was significantly in excess of the warranty offered by the manufacturers.

In the end though, I was concerned about complications should we decide to move; having a sub lease in place on the space above your roof might have caused a headache when it came to sell...

[Gunge]

I am intrigued the comments of those who say payback is very long. This should only be the case after the subsidies drop significantly next year or if you have a property with a poor roof facing/roof angle or of limited size so that you cannot install a full 4kW set.

We have a 4kW system installed in London, installed 2013, and have generated around 3700kWh in each of the last two years(the 'model' predicted 3334kWh), more than our annual electricity usage was beforehand. Occupation times mean we don't make the predicted savings on electricity usage, but our usage is low anyway so that is marginal.

Its been a good financial investment for us (around 10% if the trend remains constant), but also reduces our environmental impact.

[big_hairy_rob]

House is East facing so no real point. Would need to split the cells half on each side of roof & cannot see the point. Would consider if lived in a sunnier region & had a south facing house.

[kingpotnoodle]

I have some that were included on my new build house so it was essentially free, the installation company collects revenue for what goes back to the grid and I've seen them do 2KW+ on sunny days, aside from showing that the Energy Smart meter that British Gas sent me is otherwise next to useless because it counts what the solar generates as well as what comes in from the mains - it has no way to tell the direction of flow.

Doing things like running the dishwasher and washing machine when it's sunny means my electricity bills are lower (<£20 a month summer, >£50 winter), but I also have new-ish energy efficient appliances, mostly LED lighting and gas water heating etc so that's not all down to the solar. Trouble is peak electricity usage is evening when the sun has moved round off the panels so without a storage battery system a lot of the benefit to me is lost and goes to the grid.

Considering the area I live in is like a wind tunnel most days I think I'd be better off with a wind turbine in the garden, or maybe both that and solar, I'd probably be a net producer by a long way then - even if I did have a battery storage system.

[Gerrard]

I didn't think that any of the power generated actually goes into the grid as there would be problems trying to isolate circuits?

[LSG501]

I didn't think that any of the power generated actually goes into the grid as there would be problems trying to isolate circuits?

According to our engineers when it was being fitted power does go back into the grid. It's why the solar gets 'turned off' when there's a power cut without an expensive bit of kit, basically it's to so that workers aren't put at risk when working on lines that supposed to be turned off.

[peterb]

I didn't think that any of the power generated actually goes into the grid as there would be problems trying to isolate circuits?

Yes, excess power is exported back to the grid. The inverters self synchronise, but require the presence of grid power to operate. That way, in the event of a power failure, the inverters shut down. The solar installation will also have an isolator on the inventor output, and in the case of a string array (panels in series, feeding high voltage D to the inverter) a DC isolator as well.

[Worms]

My roof isn't directed the right way

[HalloweenJack]

already had them for 3 years now

edit:




taken august 7th after a sunny day (SSE facing roof , Eastbourne south coast) @5pm

10 x solvelo panels for a 2kw system

[tygrus]

I'm currently designing a 12v electric sub system for my next house which will be powered with solar and possibly wind, ..

12v seems a bit low to share around the house. The cable has to be thicker and the voltage&power loss is greater as you increase the current. Try nominal 24v DC or greater. 14.2v@18A using cable designed for 30A with a 16m distance to device from battery/charger = 3v drop (11.2v at device) 200w load, 54w loss (3v * 18A), <80% efficiency. Huge cost of even more copper or only supports very very small loads (eg. 50w from battery at night would have 95% efficiency).

[azrael-]

I'd be a bit hard pressed outfitting my flat with solar panels...