t an export meter. If your levels of generation are high and annual daytime consumption is low then an export meter will worthwhile, and you will need to arrange this through your electricity company.
However, as a good alternative to fitting an export meter, most supply companies offer 'deeming' of 50%, where they assume that you are exporting 50% of the power you generate. This obviously suits people well when they are using the majority of the generated power in the house, and exporting less than 50%. If you find you are exporting more than 50%, you should find out what fee (if any) your supplier will charge for installing an export meter, and if the 3p / kWh paid for exported power makes this worth it.
Our advice for new domestic installations is to go with the 50% deeming, and see how you feel after a year of getting used to the PV system. It helps to change your patterns of use where possible, so that you use generated power as it comes off the roof - eg set timers so the dishwasher comes on at 10am, and the washing machine at 12. This way you will save a higher proportion of expensive imported power (at say 16p), and decrease the proportion of power being exported (for 3p).
You may find this doesn't work for you, but it will be easier to arrange installation of an export meter after a year than to fit it straight away and then have it removed.
Commercial buildings often use much more daytime power than the PV’s will generate so an export meter is definitely not required. In such a case, all generated power is used on-site and the owners will benefit from the FiT and the saving on import bills.
OLD METERS Old meters – Modern digital import meters will slow down and stop when PV’s are supplying more power to the building than is being consumed. Old meters (with the spinning wheel) will actually reverse under these conditions and so any exported power becomes worth 3p + the 16p saved from the bill. However, using an old meter under these circumstances could be considered fraudulent.
The introduction of ‘smart metering’ will likely start with micro-generators, and these meters will be capable of recording import & export, and so will replace old meters as well as deeming.
Feed in Tariff (Clean Energy Cashback)
Feed in Tariffs replace the old grant and Renewable Obligation Certificate system, and are intended to be incentive enough for people to install renewable energy without grant funding. Payments are linked to inflation, and continue for a period of 25 years. The FiT is subject to degression which will reduce the rate, but only for new installations - once you install the system the rate is set.
The rates are:
|Size & nature of system||Payment / kWh generated|
|4 - 10kWp||16.8p|
|10 - 50kWp||15.2p|
|50 - 250kWp||12.9p|
|250kWp - 5MW||8.9p|
So for an example 4kWp system generating 3400kWh / year, you could expect:
|1.||3400 x 21p||=||£714|
|2.||1700 x 16p||=||£272|
|3.||1700 x 3p||=||£51|
|Total 1st year income||=||£1,037|
- No2 assumes 50% of the power generated is used in the home (during sunny days), offsetting usual import cost of around 16p / kWh (inc VAT)
- No3 refers to the other 50% exported to the grid at minimum export price of 3p / kWh.
The 4kWp system above would typically cost £9000 (including 2 storey scaffolding & 5% VAT).
Payback – At a cost of £9000 and with an annual benefit of £1037, this example system will pay for itself in under 9 years. This ignores the effect of inflation and electricity price rises which will continually increase the value of the system.
Energy Performance Certificates
An EPC of band D or above is now needed in order to claim the standard FiT rate for the size of your system.
Solstice Energy is qualified to provide domestic EPC's, and we know that band D is not hard to reach. Those 100 year-old, solid walled, sash windowed properties are still achieving a D as long as the basics are in place - loft insulation, good heating controls etc, and there are companies offering "no D, no fee" promises because of this confidence. The addition of a solar PV or thermal system adds a lo