Viv & Paul,
The example`s below will hopefully explain why the bill`s vary, we pay a rental fee for the meter, and pay a contracted fee for the KW. Both the contracted fee and the rental fee are X the number of days since the meter was last read or estimated. Plus the various other tax, and also the Power consumed at different rates.
Power consumed ENERGY
Contracted capacity 5,75 kW x days (
= NUMBER OF DAYS since last READING OR ESTIMATE ) x 0,056529 /kW day
Power consumed x 0,140069 /kWh
X kWh x 0,142319 /kWh
X kWh x 0,140069 /kWh
Electricity tax 4,864% x 1,05113 0,90
TOTAL ENERGY
SERVICES AND OTHER ITEMS
Rental of metering equipment (
= NUMBER OF DAYS since last READING OR ESTIMATE ) x 0,02663
TOTAL SERVICES AND OTHER ITEMS
Total amount
IVA 18%
TOTAL INVOICE AMOUNT No Power consumedENERGY
Contracted capacity 5,75 kW x days (
= NUMBER OF DAYS since last READING OR ESTIMATE ) X 0.056529
TOTAL ENERGY
SERVICES AND OTHER ITEMS
Rental of metering equipment days (
= NUMBER OF DAYS since last READING OR ESTIMATE ) x 0,02663
TOTAL SERVICES AND OTHER ITEMS
Total amount
IVA 18%
TOTAL INVOICE AMOUNT Hope this is of some help to you

.
Dave