Solar Panels - increasing price of energy make them more worthwhile?

[Deleted User]

Here, try this one, for business, but still valid to the discussion.

https://www.businesselectricityprices.org.uk/historical/

Also, my wage hasn't risen for 10 years. Does it matter to me what the bank of england says? No. The energy cost to me has still risen by the percentage given.

Mister_G

jimjames said:

Dolor said:

jimjames said:

As above check the shading on your roof and the orientation. If you are working from home and that's likely to continue then solar could well be worthwhile as it should mean you can make most use of the output during the day. If you can set washing machine etc to run in daylight hours then it will maximise your use of the solar generated. Our roof is pretty much unshaded all day and faces due South so we're on about the maximum output you're likely to get which is 3300kWh for 3kWp solar panels. If you had a battery you'd then be able to use the generated power overnight as well.

PS. I am a little surprised that you think that a 3kWp array can produce 3300kWhs/year: that would be 110% efficiency when most systems (I have had two) have an efficiency loss of up to 20%. My 7kWp array produced just under 5900kWhs in the past 12 months which was above the MCS prediction.

It's not a "think", it's our actual generation. Generation meter currently on 32300 and we're a couple of months under 10 years. As I said it's around the maximum you can get under best conditions, you're unlikely to get more than that.

http://solar-panels-review.321web.co.uk/index.php/yearly-comparison-of-solar-pv

Three most recent complete years below:

2018 was 3325 kWh
2019 was 3338 kWh
2020 was 3378 kWh

Yes, our 3kWp array (South facing 45 degrees) has produced an average of 3.2MWhs/year over the past 10 years.

n15h

countryhouse39 said:

We are lucky enough to live in an old house in the Scottish countryside (5bed, 3 reception) and as with many rural properties we aren't on the gas network. The people before us installed a GSHP for the heating and hot water, but they didn't install much in the way of insulation (out house is mostly pre 1900) so we have spent the last few years upgrading the insulation, and we installed some double glazing, but our electricity bills are still high as we use about 18-19000kwh a year...
With both of us WFH and 3 children I don't think we can reduce this much - so as you can imagine the recent massive hikes in energy prices are painful for us. We have been thinking of installing PV panels, maybe solar thermal too, but the possible savings didn't make it seem worth the outlay, however I am thinking that with the rise in energy prices that it will be worth it after all? Is anyone else in a similar situation? is it worth reconsidering so our bills go down? Can anyone advise on the best combination? we have roof space, sadly our south facing roof is also street facing and therefore unlikely to get planning permission for panels (conservation area) but we have a long west facing roof that is unobstructed. Any advise gratefully received. 

Cheers for this post OP! I have this week also been researching in having PV solar panels installed now since WFH permanently. My usage is very low at 1100 kWh a year (2 bed semi detached, only 1 person in property in Midlands). Roof at front faces East, and back faces West, and I'm thinking 6 x 250w panels should be placed as 3 on front roof, and 3 on back roof. Also been looking at whether a battery is a good investment (for storage to use in evenings/night). I haven't had any quotes yet, but researching online, I am estimating cost of £4K for panels, inverter, battery and installation. I'm sure there are more knowledgeable people on these forums that can provide guidance and whether it is worth considering. Any suggestions or guidance on installation/companies would be appreciated.

jimjames

n15h said:

countryhouse39 said:

We are lucky enough to live in an old house in the Scottish countryside (5bed, 3 reception) and as with many rural properties we aren't on the gas network. The people before us installed a GSHP for the heating and hot water, but they didn't install much in the way of insulation (out house is mostly pre 1900) so we have spent the last few years upgrading the insulation, and we installed some double glazing, but our electricity bills are still high as we use about 18-19000kwh a year...
With both of us WFH and 3 children I don't think we can reduce this much - so as you can imagine the recent massive hikes in energy prices are painful for us. We have been thinking of installing PV panels, maybe solar thermal too, but the possible savings didn't make it seem worth the outlay, however I am thinking that with the rise in energy prices that it will be worth it after all? Is anyone else in a similar situation? is it worth reconsidering so our bills go down? Can anyone advise on the best combination? we have roof space, sadly our south facing roof is also street facing and therefore unlikely to get planning permission for panels (conservation area) but we have a long west facing roof that is unobstructed. Any advise gratefully received. 

I'm sure there are more knowledgeable people on these forums that can provide guidance and whether it is worth considering. Any suggestions or guidance on installation/companies would be appreciated.

I'd suggest posting on the Green MSE board, there are lots of solar threads there and some very knowledgeable people about best options. I know some have a similar E/W orientation so would be able to give feedback. Just avoid any that do the hard sell and try to claim excessive savings from electric use as well as ramping up the electric prices over the long term. As I mentioned above some applied a 15% pa increase on unit rates to make the savings look better.

Rodders53

countryhouse39 said:I am not an expert in this stuff at all, but would like to be able to work out how to make better use of the heat pump as I feel a COP of 1.5 is pretty crap tbh . Do you have any tips on how I can 'drill down' in more detail? 

We are in the process of doing all we can in terms of insulating the property better - the roof spaces are now massively insulated so there's not much more we can do there, windows are much more expensive, but we are probably 70% double glazed now. The plan of the house is not very efficient  - its long and thin so lots of external walls. I am worried about our bills soaring, so keen to do what we can in terms of reducing it.

You'd need to ideally meter the electrical input to the heat pump (e.g. a clip-on power monitor?) and compare that with the heat output from it...  which is much more difficult to measure. AIUI (from reading stuff on forums inc. this one*) some modern HPs have some in-built metering accessed via the control panel... so you'd need to dig out the manuals to determine exactly what you have.

Correct CH heat flow-return temps (low = better COP typically), lower than normal stored HW temp (with occasional Legionella boost temp)  and weather compensation can help?   Ensuring that electrical immersion style 'boost' heaters are rarely (ideally never) used with suitable settings.

I don't own one but am trying to understand for the day I may be forced into using them. (Tho GSHP would be out of the question and it would be ASHP here).

Are the walls insulated?  Internal or external if solid and no cavity to fill?  Thermal blinds and thick curtains can reduce heat loss through windows while you save to upgrade?  {and help even in DG homes}.

* https://forums.moneysavingexpert.com/discussion/2964222/ground-source-heat-pumps

https://forums.moneysavingexpert.com/categories/lpg-heating-oil-solid-other-fuels has threads scattered around as well as the ASHP main thread.

https://forums.moneysavingexpert.com/categories/green-ethical-moneysaving has some threads, too.

2Protons

countryhouse39 said:

We are lucky enough to live in an old house in the Scottish countryside (5bed, 3 reception) and as with many rural properties we aren't on the gas network. The people before us installed a GSHP for the heating and hot water, but they didn't install much in the way of insulation (out house is mostly pre 1900) so we have spent the last few years upgrading the insulation, and we installed some double glazing, but our electricity bills are still high as we use about 18-19000kwh a year...
With both of us WFH and 3 children I don't think we can reduce this much - so as you can imagine the recent massive hikes in energy prices are painful for us. We have been thinking of installing PV panels, maybe solar thermal too, but the possible savings didn't make it seem worth the outlay, however I am thinking that with the rise in energy prices that it will be worth it after all? Is anyone else in a similar situation? is it worth reconsidering so our bills go down? Can anyone advise on the best combination? we have roof space, sadly our south facing roof is also street facing and therefore unlikely to get planning permission for panels (conservation area) but we have a long west facing roof that is unobstructed. Any advise gratefully received. 

Before looking at solar

how have you got to 18 to 19 000 kwh (which at £0.20 a KW/h that is £3800) -

is that electric or is the heat demand as that sound high for a heat pump what do you know how it was heated before the heat pump?

Do you have a energy monitor or smart meter? As I would try and see if there some resistive heating going on especially a immersion heater.  As the COP of the heat pump sounds low.

Is the GSHP feeding radiators (how high is the output temperature) or is it a hot air system?

Has your GSHP had a recent service?

Then as your problem is heating and you are in Scotland I would think you need the south facing roof to make the most of the winter sun but I would get a estimation of all the roof to how you can maximise both peak & average generation in December to see if you would generate enough at the right time to help power the heat pump and reduce the amount of electricity from the grid but i think you need an energy assessment especially if you don’t have solid wall insulation as there is likerly still grants available for that so the solar may not be the most cost effective improvement.

Is the GSHP  feeding radiators or is it a hot air system?

Then as your problem is heating and you are in Scotland I would think you need the south facing roof but I would get a estimation of peak generation at midday in December to see if it would generate 

countryhouse39

2Protons said:

countryhouse39 said:

We are lucky enough to live in an old house in the Scottish countryside (5bed, 3 reception) and as with many rural properties we aren't on the gas network. The people before us installed a GSHP for the heating and hot water, but they didn't install much in the way of insulation (out house is mostly pre 1900) so we have spent the last few years upgrading the insulation, and we installed some double glazing, but our electricity bills are still high as we use about 18-19000kwh a year...
With both of us WFH and 3 children I don't think we can reduce this much - so as you can imagine the recent massive hikes in energy prices are painful for us. We have been thinking of installing PV panels, maybe solar thermal too, but the possible savings didn't make it seem worth the outlay, however I am thinking that with the rise in energy prices that it will be worth it after all? Is anyone else in a similar situation? is it worth reconsidering so our bills go down? Can anyone advise on the best combination? we have roof space, sadly our south facing roof is also street facing and therefore unlikely to get planning permission for panels (conservation area) but we have a long west facing roof that is unobstructed. Any advise gratefully received. 

Before looking at solar

how have you got to 18 to 19 000 kwh (which at £0.20 a KW/h that is £3800) -

is that electric or is the heat demand as that sound high for a heat pump what do you know how it was heated before the heat pump?

Do you have a energy monitor or smart meter? As I would try and see if there some resistive heating going on especially a immersion heater.  As the COP of the heat pump sounds low.

Is the GSHP feeding radiators (how high is the output temperature) or is it a hot air system?

Has your GSHP had a recent service?

Then as your problem is heating and you are in Scotland I would think you need the south facing roof to make the most of the winter sun but I would get a estimation of all the roof to how you can maximise both peak & average generation in December to see if you would generate enough at the right time to help power the heat pump and reduce the amount of electricity from the grid but i think you need an energy assessment especially if you don’t have solid wall insulation as there is likerly still grants available for that so the solar may not be the most cost effective improvement.

Is the GSHP  feeding radiators or is it a hot air system?

Then as your problem is heating and you are in Scotland I would think you need the south facing roof but I would get a estimation of peak generation at midday in December to see if it would generate 

HI - just saw your reply to this thread as I am still searching for how best to reduce our bills, even more so now!
in answer to your questions - the kwh total is for all electric, not just heating & hot water, and its closer to 20000kwh tbh.
The house was extensively renovated by previous owner so the previous heating isnt really relevant but it would have been oil as we are not on the gas network. 
we don't have a smart meter - energy company tried to install one but there isn't the reception here for them to work, so i don't have any kind of breakdown for the figures sadly, i just take regular meter readings.
The immersion heater definitely isn't on. 
The GSHP is feeding 2 manifold for UFH on the ground floor, with radiators upstairs in the bedrooms.
thanks