How to tell if energy direct debit is correct

aideenj

Hi all,
I am hoping that you can help me to figure out if my energy direct debit is correct, or signpost me somewhere that can do the maths for me.
We have been with Avro energy since December and have recently been told that our Direct Debit was too low and that we are £288.39 in debit. We had been paying £84 a month. They say that our predicted usage for the year will be 3304kwh of electricity and 9508 kwh for gas and to cover this usage they will need to adjust our direct debit to £138 a month (if we pay the debit as a lump sum, or adjust it to £162 if we want to pay back the debit monthly).
However when I adjusted our annual usage on the cheap energy club it says that on this tariff with that usage it should be £931 a year ( working out as £77ish a month).
As a result I really dont know which one has done the maths correctly-avro or the cheap energy club and I cant find a calculator online that would work it out for me as a third opinion.
Just for a point of reference, we only moved to this house in November which is bigger than our last so I cant compare our usage to last year.
So hopefully someone could shed some light on it.
Thanks in advance,
Aideen.

Mr.Everready

Get your opening readings, take off the readings now. Multiply by the unit price you pay + day rate + vat. Divide by how many months usage you've had. Presto !