How does PowerGen work its Primary units

oldwiring

My son is on PowerGen for gas, and has an under payment, so I am trying to advise him. For the period 11/12/07 to 25/3/08 the total consumption was 9457kWh, 5313 prior to the 8/2/08 price rise and 4144 after. Primary kWh are listed as 714 before 8/2/08 and 338 after, making 1052 for 105 days. Now looking at the PowerGen site I read that primary units are up to 2680 kWh per year. This with my supplier's method of calculation would equate to either for each quarterly billing period to 670, and on daily apportionment for 105 days ( see above) to 770 kWh. Neither of those figures is anywhere near the 1052 that PowerGen are claiming as Primary Units. I am therefore completely mystified how they do their sums, and any help will be much appreciated.

Cardew

OW,
I have a feeling that prior to the price increase the primary units allocation was much higher. 1,143kWh per quarter(4,572 per year)???

On the last round of rises some companies seem to have increased the price of the primary units significantly and reduced the number they charge each quarter. Obviously designed to ensure that those who use very little gas in the summer pay more.

Not certain of my facts with PGen, but will be the reason if I am correct.

Have you old bills?

oldwiring

:beer:Thanks Cardew. Doing the calculation that way works almost spot on.