So now I have a solar PV system how do I make the most of it???

jackieblack

keith_r59 wrote: »

I'm due to give E.ON my readings on the 12th April and as I see it there will be three different scenarios that they may employ:

1) They will ask me for two readings, one for 31/3 and the other for 12/4 and apply the different tariff rates. However, there is nothing to stop me giving a lower figure than the actual reading for the 31/3 so that more units are at the higher rate, or say that I don't know what the meter reading was on 31/3.

2) They will just ask me for the 12/4 meter reading and perform a calculation to prorate the units across both tariffs. As March was exceptionally sunny where I live, and the start of April looks less likely to be so, that would be to my benefit.

3) They will just ask me for the 12/4 meter reading and pay all the units generated at the new rate. An even bigger benefit.

Whichever way they do it we are only talking a few pence difference for my system and in scenarios 2 and 3 there is still nothing to stop me giving them a slightly lower reading than it actually is to force more units into the higher tariff for next time.

I will report back on what happens.

According to my telephone conversation with them this morning, it will be scenario 1 - but I wouldn't be surprised if they change their minds again, so far I've had 3 conversations with them and been told 3 different things!

thenudeone

Cardew wrote: »

You don't seriously think that the idea is you should also get a further 10p/kWh(or however much you pay for electricity) for all generated electricty on top of that 3p and FIT.

That's not what I said at all, but is exactly what others have said:

grahamc2003 wrote: »

The reality is that you will be paid 3p for 50% deemed exported, and you'll get the option to use 100% of the electricity generated, which will be worth more or less than the calculations.

I need to understand this fully before I invest £12-£15k in a system.
Please go through the following line by line and identify the point at which you think my logic fails:

The true usage will be different from the assumed 50%

Whilst you will actually use more or less than 50% of what you generate, for financial purposes the utility company only has two pieces of information: your generation meter readings and your standard import meter readings.
As stated before, these will be the same whether you generate 1kWh and use it at the same time. or whether you generate 1kWh, don't use it, and later on import 1kWh from the grid. Therefore the net bills will be the same. How can they be different when the readings are the same?

The SAP calculation is very clear.
For every 1000 kWh produced you get the FIT payment (41.3p @ 31/3/11)
PLUS every 1000 units produced is
EITHER A) used in your home in which case you save what you would have paid (say 10p/kWh)
OR sold back to the grid
I'm saying A) + = 1000
With a smart meter capable of measuring export separately from imported electricity, A) and and known for certain.
Without an export meter, there is no way of knowing what A) or are, but they must still equal 1000.
What you and several other seem to say is that by changing the time (not the amount) at which electricity is consumed in the home you can arrive at a position where A) + does not equal 1000.

If the standard meter states a "usage" of 5000kWh and the generation meter shows generation of 1000kWh the utility company has now idea whether the generated 1000kWh was used whilst generating or exported to the grid.
Therefore, using the assumed 50%, A = 500; B=500, I would expect them to bill as follows:
imported (net meter reading + 50% of generated) = 5500 @ 10p (say)
less sales back to grid (50% of generated) = 500 @ 3p
If they just billed me 5000 @ 10p they would effectively be allowing me to sell generated electricity to them @ 10p/kWh, which I do not expect to happen (but I would be pleased if it did!)

Cardew wrote: »

Indeed if you have a meter that runs backward, and you go away on holiday you reading would be LOWER, but if discovered do you think the Utility company will be happy?

I don't care whether they are happy as long as it is within the scheme rules.
I don't suppose they are happy at having to pay me the FIT @ 41.3p either:)

John_Pierpoint

I think the majority of people have an importing meter that only spins one way, though I do know someone with panels whose meter (E7) does go backwards. I don't know if he is heating water in the day time now to avoid making it obvious.:D Those units would be costing him 12p (ish).
I have an electricity company's billing system that gets stroppy if the meter appears to have gone backwards (a meter reader read the E7 back to front in the summer time and I tried to get it corrected).
My meter is electronic and I'm pretty sure won't go backwards. What it does with electricity trying to go backwards I don't know.

So in the only two meter concept with uni directional meters, the FiT is in effect 41.3 + 1.5. (they cannot tell which 50% you are deemed to be exporting).

If you use electricity in the day time and the importing meter does not move you got that electricity for free.
However day time electricity is pretty well three times the cost of the raw fuel that made it because the total efficiency of the grid is only about 40%.
So if you draw one third of the demand from the mains rather than from the panels for water heating then you could be making a loss over using the gas boiler or the night rate for electricity.

If you are doing the washing/ironing/freezing/boiling a small kettle you have a better chance of doing it for free.

zeupater

thenudeone wrote: »

That's not what I said at all, but is exactly what others have said:



I need to understand this fully before I invest £12-£15k in a system.
Please go through the following line by line and identify the point at which you think my logic fails:

The true usage will be different from the assumed 50%

Whilst you will actually use more or less than 50% of what you generate, for financial purposes the utility company only has two pieces of information: your generation meter readings and your standard import meter readings.
As stated before, these will be the same whether you generate 1kWh and use it at the same time. or whether you generate 1kWh, don't use it, and later on import 1kWh from the grid. Therefore the net bills will be the same. How can they be different when the readings are the same?

The SAP calculation is very clear.
For every 1000 kWh produced you get the FIT payment (41.3p @ 31/3/11)
PLUS every 1000 units produced is
EITHER A) used in your home in which case you save what you would have paid (say 10p/kWh)
OR sold back to the grid
I'm saying A) + = 1000
With a smart meter capable of measuring export separately from imported electricity, A) and and known for certain.
Without an export meter, there is no way of knowing what A) or are, but they must still equal 1000.
What you and several other seem to say is that by changing the time (not the amount) at which electricity is consumed in the home you can arrive at a position where A) + does not equal 1000.

If the standard meter states a "usage" of 5000kWh and the generation meter shows generation of 1000kWh the utility company has now idea whether the generated 1000kWh was used whilst generating or exported to the grid.
Therefore, using the assumed 50%, A = 500; B=500, I would expect them to bill as follows:
imported (net meter reading + 50% of generated) = 5500 @ 10p (say)
less sales back to grid (50% of generated) = 500 @ 3p
If they just billed me 5000 @ 10p they would effectively be allowing me to sell generated electricity to them @ 10p/kWh, which I do not expect to happen (but I would be pleased if it did!)


I don't care whether they are happy as long as it is within the scheme rules.
I don't suppose they are happy at having to pay me the FIT @ 41.3p either:)

Hi

The assumption that A+B=1000 should really be reconsidered.

A+B can be anywhere between 500 & 1500, depending on how you use the generated electricity. The only known figures in the assumption are the figures directly related to the FiT and based on 50% assumed export, this does not necessarily mean that the actual usage will be the remaining 50% of generation. For example, if you are not at home at all the usage will be minimal, lets say 0%, if you are at home and consuming more than they are producing the usage will be 100%, but whichever the case, the assumed export will still be 50%.

It is likely that with a 4kWp system you will be paid an assumed 50% at 3.1p/kWh and use somewhere around 25%-30% of the generation worth around 10p/kWh yourself.

HTH
Z

Ragged_Trousers

Hi everybody, we are very new to this, we had 10 panels fitted to our roof end of Feb, and until this cloudy week we have been happily watching the units clock up, best week has been 70 units!! this week only 12 so far.
We applied to our provider Southern Electric five weeks ago enclosing our MCA cert but still waiting for our official registration. Will we get credited with the units we have already clocked up?
By the way our meter is also running backwards when the sun is shining!! but I don't feel inclined to notify Southern Electric until we are officially registered.
Regard Geoff

free_juice?

Ragged_Trousers wrote: »

Hi everybody, we are very new to this, we had 10 panels fitted to our roof end of Feb, and until this cloudy week we have been happily watching the units clock up, best week has been 70 units!! this week only 12 so far.
We applied to our provider Southern Electric five weeks ago enclosing our MCA cert but still waiting for our official registration. Will we get credited with the units we have already clocked up?
By the way our meter is also running backwards when the sun is shining!! but I don't feel inclined to notify Southern Electric until we are officially registered.

It may be wise to phone and ask if they have your certificate. I got no acknowledgement from Scottish Power until six weeks after submitting the cert but when they eventually made contact all was well - and they wrote to me seeking a meter reading for 31 March.

Ragged_Trousers

Hi Free Juice
Thanks for your quick reply, Phoned S/Electric mid March, they said 'by the end of the month' no news so phoned today they said it was offgen keeping us waiting!!
Hope we get paid for all the units on our meter

Regards Geoff

thenudeone

John_Pierpoint wrote: »

My meter is electronic and I'm pretty sure won't go backwards. What it does with electricity trying to go backwards I don't know.

This might be the source of the differences in opinion in numerous previous posts. I can understand designing meters not to go backwards in order to prevent fraud, but if it's true and that meter is allowed to stay post-PV installation, that means the financial payback is different to the government calculation.

John_Pierpoint

I think you are slightly missing the point.
Having a meter that goes backwards is all bonus. It is in addition to the government scheme that simply pays you for making the electricity and in absence of proof assumes half of what you produce goes "backwards" into the mains.

I've had a meter like this one for over 4 years.
Mine sits there displaying three figures in a constant loop
Night consumption
Day consumption
Both added together.

Meter readers used to be confused, but now have a tablet that reads the meter automatically somehow.

http://www.e-ssociation.net/blog/?p=33

Cardew

thenudeone wrote: »

That's not what I said at all, but is exactly what others have said:



I need to understand this fully before I invest £12-£15k in a system.
Please go through the following line by line and identify the point at which you think my logic fails:

The true usage will be different from the assumed 50%

Whilst you will actually use more or less than 50% of what you generate, for financial purposes the utility company only has two pieces of information: your generation meter readings and your standard import meter readings.
You might be getting your FIT and 3.1p from EON but your electricity supplied by British gas. You are not bound to stay with the same supplier.

EON therefore have only one piece of information(not two); and that is your PV generated output. So for 1000kWh generated EON pay you 1,000 x FIT and 500 x 3.1p.

At a later date if you get an export meter or smart meter and it is found you are are exporting say 700kWh EON pay you 1,000 x FIT and 700 x 3.1p.

BG have absolutely no interest in your PV panels - unless it is discovered that they are being 'defrauded' by the electricity meter running backwards!!!!


As stated before, these will be the same whether you generate 1kWh and use it at the same time. or whether you generate 1kWh, don't use it, and later on import 1kWh from the grid. Therefore the net bills will be the same. How can they be different when the readings are the same?

The SAP calculation is very clear.
For every 1000 kWh produced you get the FIT payment (41.3p @ 31/3/11)
PLUS every 1000 units produced is
EITHER A) used in your home in which case you save what you would have paid (say 10p/kWh)
OR sold back to the grid
I'm saying A) + = 1000

This is a wrong statement. You have an assumed sale of 500kWh and are paid for that. You could use all 1000kWh in you house or nothing. so A + B could range between 500 and 1,500.
With a smart meter capable of measuring export separately from imported electricity, A) and and known for certain.
Without an export meter, there is no way of knowing what A) or are, but they must still equal 1000.

Correct!
What you and several other seem to say is that by changing the time (not the amount) at which electricity is consumed in the home you can arrive at a position where A) + does not equal 1000.

We are indeed(prior to an export or smart meter being fitted)

If the standard meter states a "usage" of 5000kWh and the generation meter shows generation of 1000kWh the utility company has now idea whether the generated 1000kWh was used whilst generating or exported to the grid.
Therefore, using the assumed 50%, A = 500; B=500, I would expect them to bill as follows:
imported (net meter reading + 50% of generated) = 5500 @ 10p (say)
less sales back to grid (50% of generated) = 500 @ 3p
If they just billed me 5000 @ 10p they would effectively be allowing me to sell generated electricity to them @ 10p/kWh, which I do not expect to happen (but I would be pleased if it did!)

See above re EON and BG. BG will just bill you for the electricity you have consumed as shown by the normal electricity meter.


I don't care whether they are happy as long as it is within the scheme rules.
It is not within the scheme rules!

I don't suppose they are happy at having to pay me the FIT @ 41.3p either:)
It doesn't matter a jot to EON what you are paid - they just claim it back from 'the kitty'; the kitty which is funded by a levy on all electricity customer regardless of having PV or not.

Comments above in red