# How much wood does an efficient chulha save in a small dyeing unit?

Canonical: https://senseible.earth/answers/efficient-chulha-dyeing-wood-saving

Half, in BEE's Solapur report. A smokeless chulha with a grate, air damper and chimney takes a small hank dyeing unit from 36 t to 18 t of wood a year. Cost Rs 0.53 lakh, saving Rs 0.45 lakh at Rs 2.50 a kg, payback 1.18 years (2010), and about two weeks to build.

## The open chulha today

- Open fired, with no grate, damper or chimney; the dye vessel sits over the flame.
- BEE measured 6.25% efficiency; units across the cluster ran at 6 to 10%.
- A typical unit makes about 94,000 kg a year on 36 t of wood and 103,500 kWh, so 0.38 kg of wood and 1.10 kWh per kg.
- Dyeing takes 3 to 4 hours a day; the chulha also holds soaping water hot.

## What the efficient chulha adds

- A bigger combustion space with a designed grate, so logs burn fully.
- A damper to control air, and a chimney that takes smoke out of the shed.
- Flue gas routed past the vessel before it leaves, plus a small pump to circulate hot water from a tank.
- A trial chulha in a Solapur unit measured about 30% efficiency; the report rates it 25 to 30%.

## Cost and build

- Rs 0.36 lakh chulha, chimney and wiring; Rs 0.10 lakh civil work; contingency and interest while building bring it to Rs 0.53 lakh.
- About two weeks. Build it beside the old one and there is no lost dyeing time.
- Life about 10 years.

## The saving is a cautious one

Going from 6.25% to 25% efficiency should cut wood to about a quarter, near 9 t a year. The report books only half, 18 t. That leaves room for a poorer build or wetter wood. Weigh wood for a week before and after and compare kg of wood per kg of yarn.

## One unit, one year

- Wood saved: 36 less 18 = 18 t, x Rs 2,500 = Rs 0.45 lakh
- Payback: 0.53 / 0.45 = 1.18 years
- Wood per kg of yarn: 0.38 kg falls to 0.19 kg
- Biogenic CO2 avoided: 18 t x 3,200 kcal/kg x 4.1868 = 241 GJ x 112 kg = about 27 t
- The report's 25 t used 1.4 t CO2 a tonne of wood; fossil CO2 does not change

Wood CO2 uses the IPCC 2006 default of 112 kg CO2 a GJ with the report's calorific value of 3,200 kcal a kg. It is biogenic and reported separately, outside Scopes 1 to 3.

## What Senseible does here

Senseible reads your electricity bills into records with CO2. It has no factor for wood, so keep wood tonnes from purchase bills as a separate biogenic line; the green loan check shows what a lender asks for, even on a small job.

- [Green loan readiness check](https://senseible.earth/green-loan-check)
- [Solapur textiles: wood fuel and carbon](https://senseible.earth/answers/solapur-textile-cluster-wood-fuel-carbon)
- [Efficient wood hot water generator](https://senseible.earth/answers/efficient-hot-water-generator-wood-saving)
- [Firewood by the quintal: emissions](https://senseible.earth/answers/firewood-by-quintal-emissions)

Sources: [BEE, Detailed project report: energy efficient chulha, Solapur textile cluster (2010, SAMEEEKSHA)](https://sameeeksha.org/pdf/dpr/dpr_chulha_b.pdf), [IPCC 2006 Guidelines, Volume 2 Energy, Tables 1.2 and 2.3](https://www.ipcc-nggip.iges.or.jp/public/2006gl/vol2.html), [GHG Protocol Corporate Standard (biogenic CO2 reported separately)](https://ghgprotocol.org/corporate-standard)

Last reviewed 2026-10-31. Report figures are from a BEE SME programme project report; costs and paybacks are at 2010 prices. Check today's wood price.