How much coal does a Jamnagar brass foundry burn per tonne of brass: 160, 195 or 192 kilograms?

The Bureau of Energy Efficiency (BEE) Jamnagar manual prints 0.16 kilograms of coal per kilogram of brass rod in its energy tables (160 a tonne) and 195 a tonne in its savings tables. Its detailed reports use 192. Weigh your own coal against brass for a month before quoting either.

Where each number sits

• Table 2.7, foundry units by size: 0.16 kilograms of coal per kilogram of brass rod for units under 200 tonnes a year and for 200 to 400, and 0.15 over 400. In kilocalories that is 1,040, 1,040 and 1,001 a kilogram, which is 6,500 kilocalories a kilogram of coal.
• Table 2.2, annual energy consumption in different capacities of foundry units: 28 tonnes of coal for 175 tonnes a year (0.16), 40 for 250 (0.16) and 129.2 for 840 (0.154).
• Tables 3.8 to 3.10, the savings tables: 195 kilograms of coal a tonne at 1.08 million kilocalories a tonne, so about 5,540 kilocalories a kilogram.
• The detailed project reports in the same BEE series: about 192 kilograms a tonne on coal pit furnaces, covered on the coal to gas pages.

How big is the gap

195 against 160 is 22% more coal. The manual does not say why. One possible reason is that the foundry tables average whole units while the savings tables describe a single pit furnace melt, but that is a guess; the manual does not say.

What it does to your carbon figure

• 160 kilograms x 1.76 = 282 kilograms of carbon dioxide (CO2) a tonne of brass; 195 x 1.76 = 343; 192 x 1.76 = 338.
• On imported coal at 2.44: 390, 476 and 468 kilograms.
• My reading: the spread from the choice of source is large, 22% between 160 and 195, against about 10% for the manual's insulation fix (19 of 195 kilograms) and 5 to 8% for charge preheating. So a buyer comparing two Jamnagar foundries may be comparing two different source tables.

What to do instead

1. Weigh or count coal bought and coal left at the end of the month, from invoices and a stock check.
2. Divide by the brass cast that month, not the metal charged, and say which you used.
3. Quote your figure with the month and the coal type, and keep the BEE range as context only.

One foundry, one month (example)

• Coal bought 12 tonnes, stock fell by 1 tonne: 13 tonnes used
• Brass cast: 70 tonnes
• Coal per tonne: 13,000 / 70 = 186 kilograms, between the 160 and 195 the manual prints
• Carbon dioxide (CO2): 186 x 1.76 = 327 kilograms a tonne on Indian coal

The tonnes are an example. Indian coal at 1.76 kilograms of CO2 a kilogram (imported 2.44) is an estimate from India's Second Biennial Update Report; use your supplier's figure if the invoice gives one.

What Senseible does here

Self-serve, Senseible reads fuel invoices and electricity bills into monthly records; coal weighing is custom, on request. The tonnes cast and any stock count come from your own records.

• Your carbon number for buyers and banks
• Jamnagar brass cluster energy and carbon
• Coal to gas for brass melting

Sources: BEE, Manual on energy conservation measures in brass cluster Jamnagar (Winrock International India), BEE, Detailed project report: energy efficient gas fired pit furnace, 200 kg an hour, Jamnagar brass cluster (2010, SAMEEEKSHA), BEE, Detailed project report: energy efficient gas fired rotoberatory furnace, 250 kg, Jamnagar brass cluster (2010, SAMEEEKSHA), IPCC 2006 Guidelines, Volume 2 Energy, India, Second Biennial Update Report to the UNFCCC, Table 2.3 (Indian coal 1.76; list of reports)

Last reviewed 2026-11-06. Both sets of figures are in the same BEE manual. The explanation offered is the author's guess and is labelled as one.