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This may be useful to someone. re: 1.02264 conversion factor.
http://www.publications.parliament.uk/pa/cm199900/cmselect/cmtrdind/193/0012507.htm
...Memorandum submitted by the Office for Gas and Electricity Markets
GAS METERING AND THE EFFECT OF TEMPERATURE AND PRESSURE
The amount of energy supplied to a gas consumer is calculated as though the volume of gas passing through the meter had been measured at the standard temperature of 15 degrees centigrade (or 288.15 Kelvin) and the standard pressure of 1013.25 millibars. In practice the gas will, of course, be measured at the actual temperature and pressure of the gas at the meter. This is why a conversion factor is used to convert the measured gas volume to the volume at standard temperature and pressure.
This conversion factor was established in the following way. Firstly, by measuring the actual temperatures at the meter in different types of home. This found that the average temperature over the year was 12.2 degrees centigrade (or 285.35 Kelvin). The temperature part of the conversion factor is obtained by dividing the standard pressure by the average temperature (ie 288.15 divided by 285.35 = 1.0098). Secondly, the pressure part of the factor is obtained by dividing the pressure at the gas meter (as maintained by governors set at 21 millibars above atmospheric and at a height of 66 meters above sea level) by the standard atmospheric pressure. This equals (1013.25 + 21 -8.114) + 1013.25 = 1.01272.
---------------------OP Note---------------------------------
Obviously no one read that, should be (1013.25 + 21 -8.114) ÷ 1013.25 = 1.01272
-------------------------------------------------------
The multiplication of these temperatures (1.0098) and pressure (1.01272) factors gives a combined conversion factor of 1.02264.
Temperature and pressure influence the volume of a given mass of gas. This means that in extremes of heat and cold, or at a great height some meters may prove to be inaccurately recording the amount of gas used.
However, it is unhelpful to generalise. Gas leaves the ground at a certain temperature. Its temperature at the meter, however, depends on the length and location of the pipe-work to the meter and, of course, the flow of gas. If the flow rate is high the gas may not have time to warm-up or cool down.
In summer the sun can warm-up meters located outside. In winter, when gas usage is at its highest, the same meter will be cold. The effect in such a case of external temperatures on the gas measured is likely to balance out.
OFGEM is aware that customers' gas supplies at relatively high altitudes will be affected by lower atmospheric pressure. Buxton is the extreme example and is 350 meters above sea level. Atmospheric pressure there is 34 millibars less than at the average height of 66 meters above sea level. OFGEM is considering whether high altitude consumers can be identified by post code which will allow their bills to be "converted" on the basis of a more relevant pressure conversion factor...
-------------------------------------------------------------
Stutory Instrument here, http://www.legislation.gov.uk/uksi/1996/439/made
Beware some glaring errors Sched' Part 1 Calculation of Pressure Conversion Factor- the 1996 Director Generaless with some sort of responsiblity, is now sitting on the Independent Commision on Banking http://bankingcommission.independent.gov.uk/biographies/ Can you spot her?
We have to pay for the best - whatever we actually endure.
-o-
http://www.publications.parliament.uk/pa/cm199900/cmselect/cmtrdind/193/0012507.htm
...Memorandum submitted by the Office for Gas and Electricity Markets
GAS METERING AND THE EFFECT OF TEMPERATURE AND PRESSURE
The amount of energy supplied to a gas consumer is calculated as though the volume of gas passing through the meter had been measured at the standard temperature of 15 degrees centigrade (or 288.15 Kelvin) and the standard pressure of 1013.25 millibars. In practice the gas will, of course, be measured at the actual temperature and pressure of the gas at the meter. This is why a conversion factor is used to convert the measured gas volume to the volume at standard temperature and pressure.
This conversion factor was established in the following way. Firstly, by measuring the actual temperatures at the meter in different types of home. This found that the average temperature over the year was 12.2 degrees centigrade (or 285.35 Kelvin). The temperature part of the conversion factor is obtained by dividing the standard pressure by the average temperature (ie 288.15 divided by 285.35 = 1.0098). Secondly, the pressure part of the factor is obtained by dividing the pressure at the gas meter (as maintained by governors set at 21 millibars above atmospheric and at a height of 66 meters above sea level) by the standard atmospheric pressure. This equals (1013.25 + 21 -8.114) + 1013.25 = 1.01272.
---------------------OP Note---------------------------------
Obviously no one read that, should be (1013.25 + 21 -8.114) ÷ 1013.25 = 1.01272
-------------------------------------------------------
The multiplication of these temperatures (1.0098) and pressure (1.01272) factors gives a combined conversion factor of 1.02264.
Temperature and pressure influence the volume of a given mass of gas. This means that in extremes of heat and cold, or at a great height some meters may prove to be inaccurately recording the amount of gas used.
However, it is unhelpful to generalise. Gas leaves the ground at a certain temperature. Its temperature at the meter, however, depends on the length and location of the pipe-work to the meter and, of course, the flow of gas. If the flow rate is high the gas may not have time to warm-up or cool down.
In summer the sun can warm-up meters located outside. In winter, when gas usage is at its highest, the same meter will be cold. The effect in such a case of external temperatures on the gas measured is likely to balance out.
OFGEM is aware that customers' gas supplies at relatively high altitudes will be affected by lower atmospheric pressure. Buxton is the extreme example and is 350 meters above sea level. Atmospheric pressure there is 34 millibars less than at the average height of 66 meters above sea level. OFGEM is considering whether high altitude consumers can be identified by post code which will allow their bills to be "converted" on the basis of a more relevant pressure conversion factor...
-------------------------------------------------------------
Stutory Instrument here, http://www.legislation.gov.uk/uksi/1996/439/made
Beware some glaring errors Sched' Part 1 Calculation of Pressure Conversion Factor- the 1996 Director Generaless with some sort of responsiblity, is now sitting on the Independent Commision on Banking http://bankingcommission.independent.gov.uk/biographies/ Can you spot her?
We have to pay for the best - whatever we actually endure.
-o-
