How to Work Out Your Gas Bills

8/3/2019 How to Work Out Your Gas Bills

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Understanding your gas bill

This does not apply to gas tariffs where we do not apply a primary and secondary

rate, e.g. prepayment, or to certain non-standard tariffs, e.g. Tracker and SignOnline v8.

If the whole of the period covered by your bill is after 1 November 2007 the way

your bill is calculated is shown opposite. If youre concerned about an earlier

period please ask for the previous version of this leaflet.

Why do we charge in this way?Theres no standing charge on our credit tariffs so the primary rate covers the

fixed costs we have to pay in supplying gas to you, e.g. distribution and

metering costs.

For gas we charge more units at the primary rate during the winter months to

reflect the fact that most customers use more gas in the winter, and to ensure that

all our customers pay a fair share to cover our fixed costs.

Maximum units charged Percentage charged

Months at primary rate per month at primary rate per month

Nov, Dec, Jan, Feb 882 19.30

March 272 5.94

April, Oct 271 5.93

May, June, July, Aug, Sep 46 1.00

Annual total 4572 100

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Our credit prices are normally based on two rates: primary and secondary.

The primary rate applies to a maximum of 4572 kWh (units) of gas that you may

use throughout any continuous period of 12 months. Above this volume, we chargeat the secondary rate which is cheaper.

Primary rate gas is charged across the 12 months on a seasonally adjusted basis,

with more primary rate units being charged in the winter months as follows:


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How to work out your gas bill

STEP ONE EXAMPLE

How many units have you used? For this example, lets assume theseare your meter readings:

If you have an imperial meter with 4 dials, Previous Meter Read = 48400take the number of units used and multiply Current Meter Read = 48800it by 2.83. If you have a metric meter

(with 5 dials) theres no need to do this. So units used is:

48800 48400 = 400

Then multiply the number of units by the Multiply by the Calorific Value:

Calorific Value and the Correction Factor 400 x 40 = 16000

and divide by 3.6 (round the answer to1 decimal place) to give you the total kWhs Multiply by the Correction Factor:

charged on the bill. 16000 x 1.02264 = 16362.24

You can find the values for Calorific Value Divide by 3.6:

and Correction Factor on your bills. If there 16362.24 / 3.6 = 4545.1 kWhare no figures available use these industry

standard figures:

Calorific Value 40.0 This gives you the total kWh charged onCorrection Factor 1.02264 the bill.

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STEP TWO EXAMPLE

Work out the number of units to be For this example, lets assumecharged at the primary and secondary rate the bill period is 15/02/08 to 14/05/08

(our example is a quarterly bill some customersreceive a bill every 6 months)

The primary units will be charged as shown (2a) Work out the 1st month % at thein the table below: primary rate

Month Consumption profile % Take the number of days in the first month and

November 19.30 take away the start day of the bill:December 19.30 1st month = FebruaryJanuary 19.30 29-15 = 14February 19.30

March 5.94 Divide the answer by the number of days in the

April 5.93 month and round to 2 decimal places:

May 1.00 14 / 29 = 0.48June 1.00 (February 2008 was a leap year and had 29 days)July 1.00August 1.00 Multiply by the percentage for that month (fromSeptember 1.00 the table on the left) and round to 1 decimal place:

October 5.93 0.48 x 19.30 = 9.3%Annual Total 100

This equals the first months proportion of theThe remaining kWhs would then be charged 4,572 annual threshold.at the lower secondary rate.


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STEP TWO ctd EXAMPLE

(2b) Work out the middle month(s) % at the primary rate

Use the full percentage for each full month (from the table on the left):

2nd month = March = 5.94%3rd month = April = 5.93%Total for middle months = 5.94 + 5.93 = 11.87%

This equals the middle months proportions of the 4,572

annual threshold.

(2c) Work out the last month % at the primary rate

Take the last day of the bill, divide by the number of days in the last

month and round to 2 decimal places):

4th month = May14 / 31=0.45

Multiply by the percentage for that month and round to 1 decimal place:

0.45 x 1 = 0.5%

This equals the last months proportion of the 4,572 annual threshold.

Now calculate the total percentage to be charged at the high ratefor this bill

Add all percentages together from steps (2a) to (2c) above:

9.3 + 11.87 + 0.5 = 21.7%Multiply the total percentage by 4572 (round up to a whole number) to

get the kWhs charged at the primary rate:

21.7 x 4572 / 100 = 992

STEP THREE EXAMPLE

Work out the total bill For our example, lets assume our unitrates are:

Primary rate 7.904 pence/kWh

Secondary rate 2.488 pence/kWh

Take the total kWh (from Step 1) and subtract the number of kWh

charged at the primary rate (from Step 2) to get the number of kWh

charged at the secondary rate:

4545.1 992 = 3553.1

Take the number of kWh on the primary rate and multiply by the PrimaryRate pence per kWh, then divide by 100 to convert into pounds

and pence:

992 x 7.904 / 100 = 78.41

Take the number of kWh on the secondary rate and multiply by the

Secondary Rate pence per kWh, then divide by 100 to convert into

pounds and pence:

3553.1 x 2.488 / 100 = 88.40

Total before VAT = 78.41 + 88.40 = 166.81

Now multiply by 1.05 to add VAT at 5%166.81 x 1.05 = 175.15

So the total bill is 175.15

npower is a registered trademark and the trading name of Npower Limited (registered in England and Wales No.3653277), Npower Gas Limited (registered in England and Wales No.2999919) andNpower Northern Limited (registered No. 3432100) which also acts as an agent for Npower Northern Supply Limited (Registered No. 2845740) in the supply of electricity. Registered Office: WindmillHill Business Park, Whitehill Way,

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How to Work Out Your Gas Bills