# How much coal and energy per brick do Ludhiana brick kilns use?

Canonical: https://senseible.earth/answers/ludhiana-brick-kilns-coal-energy-per-brick

About 140 g of coal per brick: 14 t per lakh in Ludhiana's fixed chimney kilns, or 1.27 MJ per kg of fired brick against 1.1 to 1.2 MJ for a well run kiln. At India's coal factor that is about 0.25 kg CO2 per brick; the coal's implied heat value points nearer 0.34 kg.

## A Ludhiana kiln's season

- About 330 kilns, almost all fixed chimney Bull's trench kilns; a few have moved to zigzag firing.
- A typical kiln fires about 40,000 bricks a day from January to June, about 80 lakh a year.
- Bricks are 9 by 4 by 3 inches and weigh about 3 kg fired; 65 to 70% come out class one.
- It burns about 1,120 t of coal a season; diesel only runs the water pumps.

## Which coal factor fits

The profile puts a kiln at 728 toe for 1,120 t of coal, which works out to about 6,500 kcal per kg. That is far above typical Indian grades and closer to imported coal. Check the GCV and origin on your invoice: 1.76 t CO2 per tonne fits Indian coal, about 2.44 fits imported.

## Getting from 1.27 to 1.1 MJ

- Crush coal below 10 mm and feed 750 g to 1 kg every 20 minutes, not big lots every 45 to 60.
- Feed across at least three lines, not two, and open a new row only when the bottom glows red, about 650 C.
- Keep the cooling zone near 150 to 170 feet; seal wickets and side flues; lay about 7 inches of ash on top.
- Zigzag firing: about 10% less coal.
- Perforated or hollow bricks save both clay and coal, and the saving grows with the share of perforation.

## One kiln, one season (estimate)

- 80 lakh bricks on 1,120 t coal: 140 kg per 1,000 bricks
- Indian coal factor: 1,120 t x 1.76 = 1,971 t CO2, 246 kg per 1,000 bricks
- Imported coal factor: 1,120 t x 2.44 = 2,733 t CO2, 342 kg per 1,000 bricks
- Zigzag saving of 10%: 112 t coal, 197 to 273 t CO2 a season
- Cluster: 374,080 t coal, about 658,000 to 913,000 t CO2

Coal, output and energy from TERI's Ludhiana brick cluster energy profile. Which factor applies depends on the coal you buy.

## What Senseible does here

Senseible reads your coal invoices into season totals, at 1.76 t CO2 per tonne for Indian coal and 2.44 for imported, the two factors above; divide by bricks fired for the per brick figure.

- [Your MSME carbon number](https://senseible.earth/msme-carbon-number)
- [Indian coal CO2 by GCV](https://senseible.earth/answers/indian-coal-emissions-by-gcv)
- [Zigzag conversion and credits](https://senseible.earth/answers/zigzag-kiln-conversion-carbon-credits)

Sources: [TERI, Energy profile: Ludhiana brick manufacturing cluster](https://sameeeksha.org/pdf/clusterprofile/ludhiana-brick-cluster.pdf), [IPCC 2006 Guidelines, Volume 2 Energy (fuel emission factors)](https://www.ipcc-nggip.iges.or.jp/public/2006gl/vol2.html)

Last reviewed 2026-10-31.