Solar Panels and savings

Bianchiintenso

Freecall said:

As any estate agent will tell you, PV panels are a barrier to sale, not a show stopper but certainly a barrier to parts of the market.

The time when it was impossible to get a mortgage have passed but with tightening lending criteria returning it is unwise to do anything to a house which can make it less saleable.

Some Estate agents might have a different opinion?
Yopa: Whilst there is no hard and fast rule as to how much value solar panels can add to the overall value of your property, suggestions range from 4% to 14% on average and they are certainly unlikely to detract from the value of your home, even if they aren't the most attractive feature visually.
Rightmove: Already, features such as solar panels and heat pumps have been climbing the rankings in our keyword sort tool on Rightmove. Searches for solar panels have risen from position 500 in November 2020 to position 98 in June 2022, and heat pumps have risen from 1,000 to 190.

Freecall

subjecttocontract said:

My understanding is that UK domestic installations are limited to a maximum size of 4kwh on a single phase supply. Most, if not all domestic property is single phase and will therefore have a 4kwh limit and will not match your findings.

I am not sure whether or not you really meant to say this but am aware that others may read it and get the wrong impression.

There is no practical limit on the energy that can be taken from the grid (in a domestic context).  There is a limit on the power which can be drawn which is usually between 18kW and 24kW for a single phase supply depending on the DNO infrastructure.

Three phase installations can deliver around 60kW if required but for all practical purposes, none of these limitations affects the total energy that can be drawn.

As I say, you may not have really meant to give the impression that there is an energy limit but some read things like this and take them at face value.

onomatopoeia99

Freecall said:

jimjames said:

That may have been the case with rent-a-roof schemes historically but I find it very hard to believe that in the current energy situation any house with owned solar panels would not be more attractive rather than less attractive. With FIT payments on some systems of thousands per year it would be even more of a bonus (FIT rate 70p per kWh). Our panels provide a large proportion of our electricity with considerable excess over the summer.

I agree that the rent-roof-schemes were a particularly extreme example but nowadays we tend to be thinking more of purchased systems.

As any estate agent will tell you, PV panels are a barrier to sale, not a show stopper but certainly a barrier to parts of the market.

The time when it was impossible to get a mortgage have passed but with tightening lending criteria returning it is unwise to do anything to a house which can make it less saleable.

Rent-a-roof schemes can be a barrier to sale and / or mortgage, but wholly owned panels won't cause problems with either unless the install has been catastropically bodged and the survey says so.

Not that I'm ever moving, but my home is more desirable due to the panels and Powerwall I had installed, not less. 

Screwdriva

Our household consumes ~2300 kWh without solar. Our 4 kW PV Solar system reduces this to ~1600 kWh.

That nets a ~29% reduction in consumption. 700 kWh * .34p = £240 saved

We generate 3900 kWh on average p.a. We sell the remaining 3200 kWh at .15p per kWh = ~£480 earned. 

Total amount saved + “earned” per annum = £720 p.a.

The cost of a quality (non-Chinese) 4kW Sharp panel + Solaredge inverter system via my installer today = £5750 installed with a 20+ guarantee on everything. 

These are all actuals based on a relatively low electricity consumption household where a battery makes zero financial sense. 

I’m not sure I’m aware of a financial instrument that yields a similar tax free rate of return for 25+ years but then again, I’m no expert. 

born_again

https://youtu.be/6rqO6CfZ3zE

Tryinghardtosave

nonolerigolo said:

Hello, I wondered if solar panels give same return as savings/investing as per example below. 

Solar panels plus battery £10,000. Expected electricity bills reduction £500. Rate of bill reduction will reduce with year in service. Solar panels expected to generate electricity for 25 years. 

 Is it effectively the same as a 5% return on saving/investments. Any thoughts appreciated  Thanks

It is a tough one to calculate. I have just had a system installed that cost 16.5k - estimated to produce 5550kwh a year. It has battery storage, so I can use stored power over night. If I calculate the 5550 units at my current rate cost it is almost 1950 for the year, or 160 a month. If I kept the 16.5k in the bank at 3.1% I get 25.5 a month after tax@40%
So to me it is a no brainer, I get to save circa 160 a month on my leccy bill. Yes, the system has a finite life, but I am happy with my money earning me more than 6 times it can sat in the bank. I would have to get over 19% from the bank to get the same return. 
Plus I get to look at the app to see how it is doing all the time and bore my friends about it as well :-) 

eskbanker

Tryinghardtosave said:

If I calculate the 5550 units at my current rate cost it is almost 1950 for the year, or 160 a month. If I kept the 16.5k in the bank at 3.1% I get 25.5 a month after tax@40%
So to me it is a no brainer, I get to save circa 160 a month on my leccy bill. Yes, the system has a finite life, but I am happy with my money earning me more than 6 times it can sat in the bank. I would have to get over 19% from the bank to get the same return.

The major flaw in that method of calculation (i.e. ignoring the capital) was outlined on page one:

https://forums.moneysavingexpert.com/discussion/comment/80008683/#Comment_80008683

Martyn1981

Freecall said:

subjecttocontract said:

My understanding is that UK domestic installations are limited to a maximum size of 4kwh on a single phase supply. Most, if not all domestic property is single phase and will therefore have a 4kwh limit and will not match your findings.

I am not sure whether or not you really meant to say this but am aware that others may read it and get the wrong impression.

There is no practical limit on the energy that can be taken from the grid (in a domestic context).  There is a limit on the power which can be drawn which is usually between 18kW and 24kW for a single phase supply depending on the DNO infrastructure.

Three phase installations can deliver around 60kW if required but for all practical purposes, none of these limitations affects the total energy that can be drawn.

As I say, you may not have really meant to give the impression that there is an energy limit but some read things like this and take them at face value.

Hi. I think you are confusing import with export. Plus the description given of 4kWh is itself a bit confusing and should be 'about 4kWp', meaning they have the ability to generate 4kW in peak circumstances.

The actual rules don't limit the amount of PV installed, they limit the amount of export. This limit is 3.68kW (11.04kW 3phase). In which case a PV install can take place and the DNO (District Network Operator - 10 of these handle the distribution network in the UK) notified afterwards. If you want the ability to export more, then you need to apply for prior permission.

The reason for the 3.68kW export isn't the ability of the household cables to cope. As you say, depending on whether the house has a main fuse of 60A, 80A or 100A, then the power is ~14kW to 24kW. The concern is what to do with the exported energy if there aren't enough homes to mop it up, as the sub stations don't operate two way.* They could overheat with too much export. Also, too much export would raise the local voltage, and as it reaches 253V, the PV inverters would shut down. This solves the local problem, but also impacts the benefits of the PV, hence the export limitations.

Regarding system size, an install might be (just for example) 5kWp of panels, with an inverter capped to 3.68kW. Or even cleverer, but rarer, an inverter that caps generation based on export (not generation) so can produce more if the home is consuming energy. Then there's batteries, diverters etc etc.

The 3.68kW 'limit' fitted well with the old FiT rate change for systems that were over 4kWp (and under 10kWp), plus it fitted well with a large install, typically 16 panels of 250Wp. However, these days, that panel size is now 350Wp to 400Wp, so larger systems can be installed.


*Already, some DNO's have started to experiment with installing battery storage at sub-stations. These are large, containerised batts. They can help to import leccy when prices are lower, and reduce demand on the transmission network during peak periods. But, potentially, these could allow for greater PV export by mopping up excesses during the day.

Martyn1981

eskbanker said:

Tryinghardtosave said:

If I calculate the 5550 units at my current rate cost it is almost 1950 for the year, or 160 a month. If I kept the 16.5k in the bank at 3.1% I get 25.5 a month after tax@40%
So to me it is a no brainer, I get to save circa 160 a month on my leccy bill. Yes, the system has a finite life, but I am happy with my money earning me more than 6 times it can sat in the bank. I would have to get over 19% from the bank to get the same return.

The major flaw in that method of calculation (i.e. ignoring the capital) was outlined on page one:

https://forums.moneysavingexpert.com/discussion/comment/80008683/#Comment_80008683

But the PV return is effectively index linked, saving a proprtion of the leccy bill each year, rather than a fixed %age return.

eskbanker

Martyn1981 said:

eskbanker said:

Tryinghardtosave said:

If I calculate the 5550 units at my current rate cost it is almost 1950 for the year, or 160 a month. If I kept the 16.5k in the bank at 3.1% I get 25.5 a month after tax@40%
So to me it is a no brainer, I get to save circa 160 a month on my leccy bill. Yes, the system has a finite life, but I am happy with my money earning me more than 6 times it can sat in the bank. I would have to get over 19% from the bank to get the same return.

The major flaw in that method of calculation (i.e. ignoring the capital) was outlined on page one:

https://forums.moneysavingexpert.com/discussion/comment/80008683/#Comment_80008683

But the PV return is effectively index linked, saving a proprtion of the leccy bill each year, rather than a fixed %age return.

That's a different point though - what was being referred to is that one side of the equation involves losing the £16.5K and the other doesn't, so that needs to be factored into the calculation, rather than simply considering interest earned on that capital.