Economics of small Rooftop Solar.

[David.]

Just wondering really, our house is in the farmyard and adjoins enough good south facing roofs to support a small array, without having to put it on house.
Domestic and farm E7 electricity bill (one meter) would be under £2k annually.
Should we be considering it, or have reduced fit benefits made it unlikely we would see payback.
Thanks.

 

[Treemover]

Great question!

 

[AlexMcGowan]

More than anything it would come down to when you’re using your energy, we install a lot of domestic sized solar that makes complete financial sense, however we do also have to advise some customers that other forms of renewable generation would suit them better, purely because of their consumption patterns.

If you’ve got a lot going on in the property during daylight hours it’s definitely worth exploring.

 

[Chickcatcher]

More than anything it would come down to when you’re using your energy, we install a lot of domestic sized solar that makes complete financial sense, however we do also have to advise some customers that other forms of renewable generation would suit them better, purely because of their consumption patterns.

Thanks for posting @AlexMcGowan got me intrigued what these other forms of renewable generation this would be.
Serious looking into this myself single rate meter domestic property everything electric (air source heat pump) roof available 15Ft*40Ft south facing roof that needs a new roof anyway so open minded. But love to know what your other forms are.

 

[AlexMcGowan]

Not a problem,

At a domestic level options are limited, purely down to the low consumption, so if solar doesn’t look viable after we’ve done an initial assessment our first port of call is always energy efficient equipment and smart control, to harness the energy use from the grid more wisely, and then maybe ground source / air source of there is a large heating load, which you already benefit from.

On a commercial level our recommendations on other technology would vary on landscape, region, conditions and scale, and would consist of the usual suspects, nothing ground breaking. Solar is the only service we offer in-house, however we’re electrical engineers, not a solar installation company, so we’re not in the business of installing arrays if there are more lucrative options available to the customer.

If you ever need any input or advice on your project, or simply want to talk anything renewable, feel free to drop me an email or personal message on here. [email protected].

 

[David.]

More than anything it would come down to when you’re using your energy, we install a lot of domestic sized solar that makes complete financial sense, however we do also have to advise some customers that other forms of renewable generation would suit them better, purely because of their consumption patterns.

If you’ve got a lot going on in the property during daylight hours it’s definitely worth exploring.

I think the majority is daytime, so not getting best from E7.
Electric range cooker, and a wife who cooks/bakes, I suspect is a major culprit, and farm workshop, welding, etc.

 

[AlexMcGowan]

I think the majority is daytime, so not getting best from E7.
Electric range cooker, and a wife who cooks/bakes, I suspect is a major culprit, and farm workshop, welding, etc.

Sounds like you’d make good use of the energy. The main benefit at a domestic level is living sustainably, as opposed to actually making/saving noticeable amounts of money.

If you’re looking for somebody to look in to the possibilities with we’d be happy to help, my email address is above.

 

[renewablejohn]

Would look at a PVT system rather than just electric.

 

[David.]

Please explain, does PVT heat water as well?

 

[renewablejohn]

Please explain, does PVT heat water as well?

Yes the same panel produces both hot water and electric. pv panel is lkely to be around 20% efficient whereas pvt upto 80%.

 

[Exfarmer]

Just remember that 75% of production will be in the months April - September
Then also for south facing roofs 75% is in the hours 10-2 GMT
However I think it may well be worth looking at East West slopes since these will smooth production across the day. However the penalty is that you lose 15%
The price of installs has dropped possibly 30% since the end of Fits and electric prices keep increasing so I believe that it should be justifiable, but no get rich quick scheme.
Another option is now that there is second hand equipment out there which would be worth considering , at the right price. I would though go for new inverters .

 

[renewablejohn]

Just remember that 75% of production will be in the months April - September
Then also for south facing roofs 75% is in the hours 10-2 GMT
However I think it may well be worth looking at East West slopes since these will smooth production across the day. However the penalty is that you lose 15%
The price of installs has dropped possibly 30% since the end of Fits and electric prices keep increasing so I believe that it should be justifiable, but no get rich quick scheme.
Another option is now that there is second hand equipment out there which would be worth considering , at the right price. I would though go for new inverters .

This really is not a problem anymore. As the price has come down it now makes sense to oversize systems and then smooth demand by using smart systems, batteries and buffer tanks.

 

[Clive]

I investigated similar situation recently, didn’t stack up

 

[renewablejohn]

I investigated similar situation recently, didn’t stack up

Did you look at PVT with heat pump as it not only saves on electric but saves on heating and hot water as well.

 

[stroller]

I put a domestic system on the farm house roof for £8000, it has made about £4500 i think, if I had bought Rio Tinto shares for £28 instead it would be worth £18000 without dividend reinvestment. I won't bother again.