How much do YOU save with your solar panels?

minimike2

I have been looking into solar for a while and have found a company who will fit for me.

It is on an owned basis not leased, so I will own the entire system from day 1 and take 100% of the FIT. Paid for on a loan agreement and they give 6 months payments back to you up front.

What I am looking to establish, which is my primary reason for looking into it, is what the actual SAVINGS will be on the leccy bill.

The roof faces west. I believe they are looking at a 3kw PV system (need to check this).

I currently spend £100 a month on electricity and last year I used 11,751kWh of electricity (yes that is right and not confused with the gas!). Most of this is used between 9am and 9pm.

The figure I am unsure on is what I have been quoted as a saving. FIT they told me around £35 a month, which seems to fit in with everything I can find online. Savings they have quoted me £75 a month, but the official online tool only came back with £65 a year! This is a BIG difference. £65 a year seems REALLY low.... I understand they use a different method of calculation though.

So anyone with west facing panels - what do you ACTUALLY see in savings each month? The FIT is just a bit of a bonus at it's current rate although of course it is factored in, but I am really interested in how much I would be likely to save.

Thanks

System

I have a 2.15kWp PV Solar system and over 4 years I have averaged about 65% usage in the home saving me about 1000kWhs per year or £100 on my energy bill. Remember, you can only use so much and, in my case, this includes charging an EV when the sun is out and chores are done. With your high usage, I suspect that you have electric heating. If this is the case, then when the heating is On, the sun is low and the days are short. I have had winter days with no recorded PV solar output.

At this point, someone will leap in and shout IMMERSUN or some such piece of kit. For most people, the investment will never be repaid in energy costs saved. There is only so much hot water that a house can use during the day.

[Deleted User]

IF, you have solar panels and IF your meter is an old analogue type with a rotating barrel then you will be paying virtually no electricity at all to speak of. The meter will be running backwards ( deducting night time electricity use ) and also crediting the FIT meter. Clever ones, and they are clever, make sure that the electric meter does`nt show a reading lower than the last quarters reading.Suppliers are that stupid they don t twig !.
I`ve made enough complaints to OFGEM that these meters should be all replaced when solar panels are fitted but as usual they take no notice. Some people are on the top FIT rate of 42p a kwh (with inflation index more like 50p kwhr ). They make sure not to answer the door when a meter fitter arrives to fit a new digital meter. They want to keep their money spinner for as long as possible.

matelodave

I guess you should do some calculations to work out when you use your leccy to see if you can optimise your use. There are a few websites around that allow you to input your location together with the orientation and angle of the panels to calculate your expected generation on a month by month basis.

We are all electric, but use a heat pump for heating & hot water and my total electricity consumption over a year is around 6500kwh or just over £700 a year.

30% (about £250) is used in the summer (April-Oct) when the sun shines and solar panels are generating and 70% (about £450) in the winter (Nov-Mar) when the heating is on, the days are short and there's not much sun around.

Even if I could use all that I generated in the summer I'd only save around £200 plus a bit in the winter so as far as I'm concerned they aren't cost effective especially if you are borrowing the money to buy them and paying interest.

My calculation is that a 4kwp system on my roof facing southwest with a roof angle of 35 degrees could generated around 3800kwh a year but I would not be able to use most of it as I don't use much leccy in the summer.

minimike2

My heating system is Gas.

The reason my electricity consumption is so high is that I keep reptiles. 10 Vivariums at 30c + all day soon adds up. The "good" news is that during the night those temperatures drop considerably and most require NO night time heating, so my main use is between 9am and 9pm, so the right time window in terms of using the solar.

I also work from home most of the time, so things like phone charging, laundry etc is all done during daylight hours.

Even if the system I got generated 4000KWh a year that is still only a third of my usage which increases in winter as the heating systems on the viv need to work harder. I just really fail to see where this guy got his £75 a month reduction to my bill figure from.

matelodave

Here you go - insert your post code and a few other parameters (orientation & tilt angle) and you can get a table of anticipated monthly generation. http://pvwatts.nrel.gov/ and it's not a lot in the winter

System

Do the sums. If you could use all of the output from a 3kWp system (about 2700kWhs/year) at 10p a unit then you would save £270 on your electricity bill. Check the assumptions on your quote. Some installers play the silly game of offering a box of LED bulbs and then compounding the energy savings at 8% per annum ( the magnifying power of compound interest). Also take into account that once smart meters are rolled out then you will only get paid the export rate for the energy that you export.

minimike2

So according to that I will generate around 3500kWh p.a

The cost of my electricity is 2.79ppkWh.

So that is £97 a year..... So nothing like £75 a month.
Even with the FIT that's only another £140 income a year, so £237.

The cost of the panels plus loan interest over 10 years is £9480. So it's going to take 40 years to break even, so in the lifespan of the FIT and of the panels it is likely I will lose out, unless the cost of electric goes astronomical.

I am either totally missing the point of something or I have just been given a load of duff figures by a sales person.

matelodave

who's your leccy supplier - I wish I could get mine at less than 3p kwh.

Mines 10p/kwh plus standing charges and that's the cheapest I can find where I live in Cambridgeshire (GB Energy)

minimike2

Oh wait, that's my GAS rate. Duh.

Electric is 8.63 with 18.9p/day standing charge. Its the British Gas MSE collective deal.

Even then I only save £300 a year so still not worth it.

Cardew

minimike2 wrote: »

So according to that I will generate around 3500kWh p.a

The cost of my electricity is 2.79ppkWh.

So that is £97 a year..... So nothing like £75 a month.
Even with the FIT that's only another £140 income a year, so £237.

The cost of the panels plus loan interest over 10 years is £9480. So it's going to take 40 years to break even, so in the lifespan of the FIT and of the panels it is likely I will lose out, unless the cost of electric goes astronomical.

I am either totally missing the point of something or I have just been given a load of duff figures by a sales person.

You will get better information in the 'Green and Ethical' section of MSE as that is where all the experts post.


However you have been given duff information by the sales person - which is not unusual!


For a start, even a 4kWp system should cost under £5,000.


If yours is a 3kWp west facing system, you will be lucky to generate 2,500kWh per year, even 'down South'


Most people can use between 25% and 50% of that in their house. You could buy a device like a Immersum to divert electricity to your Vivariums. and save a bit more.


Are you sure you have not mistyped electricity cost at 2.79p/kWh and it should be 12.79p?


Edit. Posts crossed re electricity price.