Solar PV - economics?

[DonkeyApple]

Evanivitch said:

You can't provide legislation for every ****.

You can. You could just ban the sale of solar panels to domestic users. No manufacturing pollution, no recycling pollution, the money could be invested into something that was actually environmental.

It's rubbishy tech that's sold to gullible punters or apex consumers who use eco products to try and justify their destructive shopping habits by shifty door to door types and spiv firms. All happening in a first World Country that is steadily making its Grid energy clear we each year and will be continuing to do so.

For the consumers who aren't being duped by snake oil vendors it's really just another product feeding their consumption habits.

A hyperbolic couple of paras but domestic solar really isn't an eco solution and in many cases it's environmental vandalism.

The Grid is cheaper, cleaner for a long period and in the UK by the time your generation has paid back the production, shipping and installation pollution the Grid will be even cleaner. Plus, if anyone actually cared about the environment they'd spent that £10knon doing something positive instead of buying a another new gadget for their house.

[loskie]

If I was doing solar now it would be Solar Thermal.

PV was only worth it when the FIT payments were decent not since.

And that's obviously not down to environmental considerations.

[bearman68]

I bought some cheap solar panels off Ebay, and chucked them on my shed roof. I didn't ask for permission, didn't have the MSC inspected or certified, and I put them up myself, but had an electrician come and check they were installed correctly.
On a good day, it's quite easy to generate 6kw/h, and I suppose 25kwh per day.

I run the house on some of it, and any export is chucked into the hot water tank.
Between Feb / march and October it's rare for me to have to supplement the hot water with fossil fuels.

So I'm saving I estimate about £300 per year, on a £2.5k investment, with no FIT. Not huge, but noticeable, and in my head, it certainly stops the burning of fossil fuels in my house.

[DonkeyApple]

I think Green Energy are the only firm in the UK that aren't selling eco smoke and mirrors via offset credit arbitrage and this is their current rate:

Gas- standing 31.31p and 4.62p per kWh

Lec- standing 34.72p and 20.15p per kWh

I don't know how that compares to normal deals which are getting steadily more renewable as a matter of course but you've got to be running a lot of crap, a lot, before spending any money on self generation and all the pollution etc makes real sense.

I think that industrial solar at points these days even hits 30% of the Grid's production. And wind has apparently hot 60% at points.

With the Grid aiming to be carbon free by 2025 I'm not sure that domestic solar, given its costs, the inefficiency and the pollution caused in manufacturer, shipping, installation and finally disposal has a hugely positive argument.

Especially if one uses any gas when the most sense is to allocate any investment in switching away from using that.

Personally, when they become financially prudent I can see greater merit in spending money on energy storage rather than generation but then it seems likely over coming years that I tra day electricity costs are likely to smooth out as more EVs, therefore households increase their off peak demands and reduce peak demands.

[Jambo85]

DonkeyApple said:

Evanivitch said:

You can't provide legislation for every ****.

You can. You could just ban the sale of solar panels to domestic users. No manufacturing pollution, no recycling pollution, the money could be invested into something that was actually environmental.

It's rubbishy tech that's sold to gullible punters or apex consumers who use eco products to try and justify their destructive shopping habits by shifty door to door types and spiv firms. All happening in a first World Country that is steadily making its Grid energy clear we each year and will be continuing to do so.

For the consumers who aren't being duped by snake oil vendors it's really just another product feeding their consumption habits.

A hyperbolic couple of paras but domestic solar really isn't an eco solution and in many cases it's environmental vandalism.

The Grid is cheaper, cleaner for a long period and in the UK by the time your generation has paid back the production, shipping and installation pollution the Grid will be even cleaner. Plus, if anyone actually cared about the environment they'd spent that £10knon doing something positive instead of buying a another new gadget for their house.

An interesting perspective! You’ve missed a bit though and it’s increasingly important - there’s a secondary effect which is that it incentivises people with PV panels (financially and psychologically) to shift their demand to periods of high PV output. E.g. using the delay function on the dishwasher/washing machine in the morning to have it come on at midday when it will run for free with no emissions, or close to it.

[Nimby]

loskie said:

If I was doing solar now it would be Solar Thermal.

PV was only worth it when the FIT payments were decent not since.

And that's obviously not down to environmental considerations.

You can, at a price, get combined PV and thermal ("PV-T") panels.
The PV cells work more efficiently at cooler temperatures so it's a win/win step - more electricity than PV, and hot water - but still barely economical due to much higher installation costs.

[DonkeyApple]

Jambo85 said:

An interesting perspective! You’ve missed a bit though and it’s increasingly important - there’s a secondary effect which is that it incentivises people with PV panels (financially and psychologically) to shift their demand to periods of high PV output. E.g. using the delay function on the dishwasher/washing machine in the morning to have it come on at midday when it will run for free with no emissions, or close to it.

Yup, there will always be positives but I've been looking at solar, batteries and various things like heat source pumps for years and the numbers never come close to making any financial sense at all. Plus, there is little true eco argument due to the infrastructure involved. And each year as the kit tends to become a little bit cheaper and a title more efficient the electricity from the Grid becomes cleaner and cleaner so maintains that gap.

I do feel that it is an extreme case where not buying from the Grid, spending a huge capital sum upfront and instigating a load of infrastructure spend makes either financial or environmental sense. Historically, the bulk of residential solar installations are at best misspelling scandals and as the Hrid trends to zero carbon quite rapidly any eco credentials evaporate by the day.

[Condi]

DonkeyApple said:

I think Green Energy are the only firm in the UK that aren't selling eco smoke and mirrors via offset credit arbitrage and this is their current rate:

Gas- standing 31.31p and 4.62p per kWh

Lec- standing 34.72p and 20.15p per kWh

I don't know how that compares to normal deals which are getting steadily more renewable as a matter of course but you've got to be running a lot of crap, a lot, before spending any money on self generation and all the pollution etc makes real sense.

I think that industrial solar at points these days even hits 30% of the Grid's production. And wind has apparently hot 60% at points.

With the Grid aiming to be carbon free by 2025 I'm not sure that domestic solar, given its costs, the inefficiency and the pollution caused in manufacturer, shipping, installation and finally disposal has a hugely positive argument.

I don't understand much of this tbh. I have no idea what you mean by "offset credit arbitrage" when discussing renewable energy. I presume you mean renewable obligation certificates which is how everyone claims to be green. At 6pm in the middle of winter when the wind isn't blowing and it's -5 degrees outside then grid will be powered by coal gas and nuclear. And maybe some hydro. It doesn't matter who you buy from, the same electrons come down your wire.

Regarding solar - most UK solar is embedded (ie small installations connected to the distribution network), and so the term "industrial solar" doesn't mean much. There is comparatively little large scale solar, but a lot of smaller installations (4-50kw) which essentially just net off demand. You are right saying it can do about 30% of national demand though.

[Evanivitch]

DonkeyApple said:

You can. You could just ban the sale of solar panels to domestic users. No manufacturing pollution, no recycling pollution, the money could be invested into something that was actually environmental.

Why assume only domestic users have the capacity to be *****?

[Tlandcruiser]

This is making me question whether to go ahead with the solar panel install!

I have 6 x380w panels being installed on a southernly facing roof for £2,400. My thinking is by only installing six panels, it would be enough to cover most of my electricity usage during the day without generating excessive power that gets feed back into the grid, for an average return between 3p to 5p depending on the tariff.

My wife runs a dog grooming business from home, so we do consumer more than average power during the day especially considering there is: aircon, electric shower and various driers.

Maybe I would get a better return on cavity wall insulation of the house!

[rxe]

Tlandcruiser said:

This is making me question whether to go ahead with the solar panel install!

I have 6 x380w panels being installed on a southernly facing roof for £2,400. My thinking is by only installing six panels, it would be enough to cover most of my electricity usage during the day without generating excessive power that gets feed back into the grid, for an average return between 3p to 5p depending on the tariff.

My wife runs a dog grooming business from home, so we do consumer more than average power during the day especially considering there is: aircon, electric shower and various driers.

Maybe I would get a better return on cavity wall insulation of the house!

There is no point in doing it at all if you are exporting. Even taking the 4.1 MWh that our 4kW system provides, that would be £205 a year in revenue if you export. If you use it all then you could displace £600 of power fees - you’d need to set up the dog water and driers to optimise for consumption. I’d look at your consumption today, and see if you can get it to be a constant 2KW load between 07:00 and 18:00 - if you can do that, then you stand a chance.

[snowman99]

Anyone got a guide or video to make a really cheap solar water heater? To heat a paddling pool maybe.

I put a dark cover on the pool (8ft by 6 inches deep) and it got really really hot just in the sun with the cover on.

My theory is that surely something with black pipes on a board must do better, not sure if you need a pump or can make the water flow by itself?

[gmaz]

snowman99 said:

Anyone got a guide or video to make a really cheap solar water heater? To heat a paddling pool maybe.

I put a dark cover on the pool (8ft by 6 inches deep) and it got really really hot just in the sun with the cover on.

My theory is that surely something with black pipes on a board must do better, not sure if you need a pump or can make the water flow by itself?

Get an old radiator, paint it matt back, incline towards the sun, feed the cold from the pool to the bottom and the warm back to the pool out of the top.

[DonkeyApple]

gmaz said:

Get an old radiator, paint it matt back, incline towards the sun, feed the cold from the pool to the bottom and the warm back to the pool out of the top.

And next week in 'Traveller Weekly': How to remove a dag from a child's arm.


Didn't pools used to be heated via this principle on the old days before everything became about wasting as much as possible to save the planet?

[Chris Type R]

gmaz said:

snowman99 said:

Anyone got a guide or video to make a really cheap solar water heater? To heat a paddling pool maybe.

I put a dark cover on the pool (8ft by 6 inches deep) and it got really really hot just in the sun with the cover on.

My theory is that surely something with black pipes on a board must do better, not sure if you need a pump or can make the water flow by itself?

Get an old radiator, paint it matt back, incline towards the sun, feed the cold from the pool to the bottom and the warm back to the pool out of the top.

Something I've not tried, but that someone has suggested is to use a solar powered fountain pump. Idea being you'd only circulate when there was enough sunlight to run the pump. I'm sceptical about being able to generating enough pumping power myself....

I think it's challenging to achieve a 'cheap' solution if you're using pool connectors, quality hose etc

A solar powered pump would also avoid one having to run the mains powered pump for long periods.

These mats might make a good starting point - https://www.ebay.co.uk/itm/331835669114

I bought some 6m * 80cm last year but did not fully utilise them - we also run an air source heat pump - and have electric solar panels. In theory the solar PV is powering the air source heat pump during the day. Some man-maths might have been applied. Our 'paddling pool' is 5000 litres iirc.

Edited by Chris Type R on Tuesday 22 June 08:50

[Drawweight]

My daughter and her OH just installed solar panels on their house.

It’s South facing so gets the sun all day.

I think she said it cost about £9k.

I’m not informed enough to comment on it to them (not that I would anyway, it’s their life) but reading up on it it no longer makes much economical sense.

Is retro installing solar panels now a waste of money?

[Chris Type R]

Drawweight said:

Is retro installing solar panels now a waste of money?

I'm not sure there's an investment case for it any more and in my view the capital is not fully recoverable (if at all) if a decision is made to move property.

Generation is mainly in summer months when you typically have lower energy requirements. Unless you're running pool heaters/pumps and aircon etc

Ground source heat pumps are probably more effective, but more expensive.

[Canute]

Hi,

I'm just about to start diving into this subject and have had a quote but not sure how to make sense of the maths. (numbers was not my strong point).

We are looking at a 50-panel system with a forecasted production of 14,194KW per year
We use around 20-23,000 KWH per year just depending on what kind of winter we have.
The total cost for this system is £16K

Also to note, I'm in Sweden so electricity prices are eyewatering. I pay around £2.5K a year for electricity.

If anyone could kindly help me make sense of the economics of it that would be great.

We would probably finance the project with an additional mortgage to our house with an interest rate of about 1.7%

[superpp]

Drawweight said:

My daughter and her OH just installed solar panels on their house.

It’s South facing so gets the sun all day.

I think she said it cost about £9k.

Sounds VERY expensive, my system is 4.8kw (16 panels) 3 years old and cost £4900 installed.
If paying around twice the going rate, the return on investment has gone.

[Zoon]

soofsayer said:

2Btoo said:

soofsayer said:

I have been dissuaded from having pv panels at ground level by 2 installers. I have a perfect spot for a large array but have been told that installation costs (hardware and time) is much higher than roof mounted (which is fairly simple),

Sounds pretty rum. Installing panels at ground level is harder than putting them on a roof a couple of storeys up? Points about shading and vegetation may be relevant but this first one sounds like someone is pulling a fast one.

Maybe, I am no expert on it but that was the advice, and I think I’d need planning permission for a ground installation due to the location and size.

Sounds like rubbish to me. How big an array are you talking?