Vapi's chemical cluster profile prints two energy totals, 92,645 and 100,127 tonnes of oil equivalent (toe): which is right, and is its gas heat value per kg or per cubic metre?

Question

Accepted Answer

Use 100,127 toe. The lines of The Energy and Resources Institute's (TERI) Vapi table add to it: 81,032 gas, 1,299 oil, 17,797 power. The text says 92,645. Today's factors land within 2% of its carbon dioxide (CO2) figure. The profile prints the gas value per kg, but its line only fits per standard cubic metre (scm) (our reading). Section 5.2.2 says the cluster's energy use is estimated at 92,645 toe. Its Table 5.2.2 prints a total of 100,127 toe. The lines add to 100,128: natural gas 81,032 (93 million scm), light diesel oil, furnace oil and diesel 1,299 (1,486 kilolitres) and electricity 17,797 (207 million kilowatt hours (kWh)). The 1 toe gap is rounding. The text also gives shares: heat 76% and power 24%, and gas about 76% with electricity 22%. The table lines give gas 80.9%, oil 1.3% and electricity 17.8% of 100,127 (our arithmetic), so heat is 82.2%. The report does not say why. We could not find the cause, so treat the text totals and shares as unexplained and use the table lines. Its lines add up, and today's factors on those lines land within 2% of the carbon figure the report prints. At today's factors, gas is 93 million x 2.05 kg = 190,650 tonnes of CO2, electricity 207 million kWh x 0.675 = 139,725 tonnes, and oil 1,486 kilolitres x 2.645 kg a litre = 3,930 tonnes if all of it is diesel. The sum is about 334,305 tonnes, 1.6% above the 328,959 tonnes the report prints. At the furnace oil factor the gap is 1.8%. The report prints no factors and is from 2020-21, so this is a consistency check, not evidence for either total. It is a check, not a proof. Table 5.1.1 lists natural gas from Gujarat Gas Limited at "8750 kCal/kg" and "Rs 61/SCM". The cluster line only works per scm. 93 million scm at 8,750 kilocalories is 81,375 toe, and the table has 81,032, which is 8,713 kilocalories per scm (our arithmetic, at 10 million kilocalories a toe, which the profile does not print). The Ahmedabad profile by the same authors prints the same 8,750 as kCal per SCM. Read the gas line as per scm. Take gas in scm from your gas bills and use the heat value printed on the bill if there is one. Take power in kWh from the electricity bills and any diesel in litres from generator invoices. Multiply each by its own factor. Compare with the table lines, not with the text shares. If you have seen 76% quoted as the gas share of Vapi's energy, that is the text. The table lines give 81%.

Vapi's chemical cluster profile prints two energy totals, 92,645 and 100,127 tonnes of oil equivalent (toe): which is right, and is its gas heat value per kg or per cubic metre?

Three figures that do not agree

Checking the table against the printed carbon figure

Gas heat value: per kg or per scm

What to use for your own unit

The check, line by line

What Senseible does here