Help and guidance please on solar energy

tunnel

Love_Solar wrote: »

1)What price should the customer pay for a 4 kW System ?

2)What would be the return on investment on this solar PV System?

3)What would the customer save on their electric bill in the first year, remember that the customer is paying 10.735per per KW for electric with First Utility?

4)One other point is that on the Energy Saving trust website they quote the customer would use 25% of what the solar PV system generates, and would export 75%.

1) A friend of mine has just ordered his 4kWp system for £4900 with a Geo solar 2 monitor thrown in for good measure so anything over £5k to me for a standard install is getting expensive
2) That would depend on the initial cost now wouldn't it, but I've seen anything up to 18%
3)Who knows but experience on these forums says it all depends how big a system and how often the owner is at home during generation to make the use of it
4)25% is about right, no disrespect to ASG customers but I believe a large proportion are retired or nearing retirement and are at home far more often, hence able to consume more of the generated power, that certainly fits the bill in my village where we are peppered with ASG

pinnks

One thing that annoyed me when I was getting quotes is that the whole industry seems focussed only on the FiT, to the detriment of the spread of produced watts hour-on-hour over the day - you can't store this stuff so if you are not producing evenly over the day you will end up importing and exporting more as your consumption will be relatively even as you make tea in the morning, at lunch time and so on.

I could have gone split roof from the outset but everyone who quoted said, it's not worth the extra £300 or so for extra scaffolding as the FiT would only be about 5% higher.

What nobody told me was that with a WSW-facing roof the bell curve of optimal production is basically only one-sided. I got 100-200W until the sun peeked round past the due south mark when it jumped within 30 minutes to max and then bell-curved down for the rest of the day. Don't forget your kettle will be 2kW+, coffee machine 1.2kW and so on.

What this means, especially if you are at home for much of the day as a retired person(s), is that you nowhere near meet consumption requirement in the morning and then exceed most requirements in the afternoon, apart from high-wattage appliances like washer (2.4kW), drier (2.8kW), dishwasher (2.4kW) etc.

This frustrated me no end. Indeed it led to me shelling out a load more money to put a second system in on that south-facing roof, hence my current config. I now rise quickly (by about 9am at this time of year) to about 1.8kW and stay at, at least that level or up to 5kW, for the rest of the day until about 7pm, when it drops as the sun sets.

Had I known then what I know now - or found this forum at that time - I think I would have maxed out the panels (23 x 327W rather than my 21 x 250W panels) and taken the lower FiT on the whole roof. I would also have gone SolarEdge as I have shading from a chimney from about 4pm on the south roof. True, I then become a major exporter but the returns are still excellent and your own consumption will be the highest possible as you will almost always cover the use of those "hungry" appliances. At 5.25 kWp I am already in the serious exporter camp I guess...

I am not an installer and have far less knowledge that Mart or Tunnel and find their contributions are invariably level-headed and aimed at helping those who are struggling to make what is still a substantial financial investment. And no, they are not paying me:rotfl:


Hope this helps inform the OP's thinking.

tunnel

Pinnks, its about time you invested in a travel kettle at 1kW or under, no way I'd run the risk of a 2/3kW element one these days!

pinnks

Just done that but didn't want to clutter the post.

hethmar

Pinnks, as a pensioner yourself I am concerned that it takes so long to make back the intial installation costs - do you feel its worthwhile?

Also, my OH is now saying that he read there will be smaller tile sized panels coming onto the market shortly? He is concerned how an array on the street facing roof will be unattractive and possibly put off buyers if we do downsize.

pinnks

I am not a pensioner (quite) - apols if I confused.

I have had my large system for two years and the smaller one for 15 months. Total FiT payments to date are about 14% of outlay. Remember, I took the expensive route of two separate installs.

I have roughly halved my consumption (down by about 2750kWh), which at 11p per kWh is about £300 per annum. That is a lot when you read what the experts on here advise but I have been recording use for about 6 years now, so have good records. Even though we had gone LED lights and TV etc. and were energy conscious before going PV, some of that saving will be down to us getting even more energy conscious and getting the hang of serial-living to max own consumption, i.e. kettle then coffee machine, then open fridge etc.

I also have a diverter which saves me about £80 of gas per year.

This year I have started diverting to two oil radiators too so mop up more savings in spring/autumn.

Add that lot together and you get some 20% return over two years of 1 system and 15 months of the other on the lower FiT as it took me over 4kWp.

Add RPI to the FiT and something for leccy and gas inflation and we are probably looking at about 7 years repay the total, staggered, outlay once the second system is fully included. Could be less with the space heating now adding to own consumption and allowing the gas to be off for another 2 months a year.

I plan on being around at least that long, so I think it worth investing and of course you have the satisfaction of not paying so much to you energy provider.

Martyn1981

Love_Solar wrote: »

First of all do you agree with my profit for this system or should it be lower?

What price should the customer pay for a 4 kW System ?

What would be the return on investment on this solar PV System?

What would the customer save on their electric bill in the first year, remember that the customer is paying 10.735per per KW for electric with First Utility?

One other point is that on the Energy Saving trust website they quote the customer would use 25% of what the solar PV system generates, and would export 75%.
On a shade greener website they quote a saving of up to 40% of the customer’s bills, not quite the same as consumption saved but they have installed over 55 thousand solar PV installations and they do have a lot of grafts and tables on this page.

I think we all have the end user best interests at heart and a small disagreements about what percent of price increase on energy per year is taking us off the subject.

I think your profit figure should be lower. The FiT and export are simple to work out, and most folk on here use PVGIS to get an extremely accurate guesstimate of generation.

Leccy savings will always be a little controversial, and will depend on consumption (high in this case) and the ability to make best use of, during the day, also good in this case. However, I feel quite strongly about over egging the leccy savings, especially if the install is marginal, though that's not clear here.

My main concern though is the energy price inflation assumptions being used. Hopefully the info I've posted will make you think for a second. I described it as 'an idiot check', as sometimes in life we go along with 'facts' and assumptions without stopping to think if they are possible. In the case of leccy prices, they rose quickly mainly due to gas price rises. That doesn't mean that they can rise like that forever, and I gave info on some of the max prices already in existence - though these will rise with RPI since they are subject to normal inflationary pressures such as material costs, labour etc.

Apologies for going extreme, but prices can only go so high before everyone would simply install PV and batteries, and a back-up generator. We have a price for PV generation already of 10p/kWh or less. Battery storage is probably around 10p/kWh, though the off-gridders with their FLA traction batts are nearly half that if you include scrap lead value. These prices are still falling. So there has to be a reality price ceiling, beyond which the market simply can't go.

In my opinion, you should just use RPI for the energy savings too, whilst this may be slightly conservative, it will act as a buffer against panel degradation and falling production over time (perhaps -10% in 20 to 25 years time). That would knock around £2k off your leccy savings figure (and shut me up too!)

I also don't agree with your arguments for smaller systems. Whilst leccy savings are becoming more important, they are still small compared to the FiT and export (for most). So ROI is mainly dependent on system size and cost. For a simple example, let's say a 2kWp system will cost £4k and a 4kWp system will cost £6k (hopefully less now, but the numbers are nice to play with).

Because of all the fixed costs, the extra cost of doubling generation is only 50%. That improves ROI significantly, even if leccy savings only increase by a much smaller amount.

So that's why I disagree with your numbers. However, I very much appreciate your willingness to discuss these issues, and to give full and frank replies. I'm far less convinced now that you had any intention to mislead, but I (and others on here) are quite protective when it comes to potential PV'ers. Have a read of this thread if you want to see why some of us are a little jumpy:

I've been a massive fool...My planet UK Solar.

I'd go with the EST's 25% figure. It's a fair starting point. ASG's 40% saving probably isn't bad either. In my case I consume about 32% of generation, cut import by nearly 50%, and save approx 40% on my bill (due to standing charges.) However it's important to understand that those 3 things (% of consumption, % of import and % of bill) are different.

Mart.

Martyn1981

hethmar wrote: »

Pinnks, as a pensioner yourself I am concerned that it takes so long to make back the intial installation costs - do you feel its worthwhile?

Also, my OH is now saying that he read there will be smaller tile sized panels coming onto the market shortly? He is concerned how an array on the street facing roof will be unattractive and possibly put off buyers if we do downsize.

Whilst I really like PV, and think it's a great idea for most, you've set off a couple of alarm bells with me.

You've mentioned that you're pensioners and are concerned about payback time. Whilst I hope you are fit and healthy, you do need to consider that it'll take around 10 years for most installs to repay the initial investment. Over 20 years PV is a great investment, so long as you don't pay too much, but you do need to think 10+ years.

Secondly, you've mentioned moving (downsizing). As above, you probably need 10 years to get your investment back. Buyers may be encouraged by the PV, and the savings and earnings, that they'll take over, but it's also possible that a prospective buyer won't want, nor like the PV.

I don't wish to be negative, but I think you do need to have a quick think about these issues before jumping in.

On the other hand, if you've got £5k sitting in a cash account earning you 1% (£50) a year, then £600 a year is a bit nicer, so long as you appreciate that with this investment the capital is gone, replaced by a fixed asset (on your roof).

Mart.

EricMears

I can see an argument for not putting an array on the roof that will always generate far more power than you really need.

However, to maintain my baseload (perhaps higher than most at 500W) and be able to boil a 500W kettle whenever I want, I'd really need a system that produces 1kW throughout the day and throughout the year. Even at this time of year my 4kWp system doesn't produce 1kW all day and in December I'm very lucky if it creeps up to that level at Noon.

If I was thinking of adding more panels, then on output grounds my 'cap' would have to be around 50kWp (or as much of that as I could squeeze onto the property &/or afford )

Love_Solar

I have taken your comments on board about the leccy price increases per year and will adjust my calculation when seeing customers in the future.

I have sent out a survey to a number of my past customers to find out what their saving have been over the past years.
Here is that survey and if any one wants to complete this online please feel free to do so.

Q1
What is the size of your solar PV system?
Q2
What was your consumption for 12 months before you had your solar PV installed?
Q3
What is your consumption per year now with the solar PV system installed?
Q4
What are you paying for your electric per KW now and would you like to know if you can get a better rate?
Q5
What do you think you have saved per year by installing solar panels.



Another couple of question for you to answer here

You have four properties each property having four people living there, two adults and two children, all the adults work so out all day and children go to school, so during the week no one is at home.

They all have a 4 kW Solar PV system installed which generates 4000 KWh per year per house as they all face the same direction. The only difference is the family electrical consumption per year. They all pay the same price per kw and that is 11p per kw to keep it simple.

1st family use only 2000 kwh per year
2nd family use 4000 kwh per year
3rd family use 6000 kwh per year
4th family use 8000 kwh per year

What savings per family do you think they will make per year?

Question
You have again four properties with the same amount of people living in them as above but this time they all use the same amount of electric per year, the National average of 3500 KWh per year, this time they all have different size solar PV systems installed.
1st property has a 2 kw solar pv system fitted generating 2000 kw per year
2nd property has a 2.5 kw solar pv system fitted generating 2500 kw per year.
3rd property has a 3 kw solar pv system fitted generating 3000 kw per year
4th property has a 4 kw solar pv system fitted generating 4000 kw per year.

What amount of KWs and percentage of total generation will each property save from the generated solar power?

When I receive my results from my small survey from my past customers I will publish online.

With regard “I’ve been a massive fool My Planet”, this is the company which I had to investigate in Spalding and court action is going to take place for miss selling.