What does an economiser save on a Panipat textile unit boiler?

An economiser saves 5 to 8% of boiler fuel in the Panipat survey by The Energy and Resources Institute (TERI), paying back in up to 8 months. It uses the hot chimney gas to warm the water going into the boiler, from 30 to 35 degrees Celsius up to 75.

What an economiser is

TERI’s table lists chimney gas at 220 to 310 degrees Celsius for boilers without heat recovery. That heat is thrown away unless the boiler has an economiser; some in the cluster do. An economiser is a pre-warmer: a set of pipes in the chimney that heat the feed water, the water going into the boiler, before it gets there. The boiler then needs less fuel to finish the job. It is like using the heat from the pan to warm the water you will pour in next.

What the survey table prints

• Existing: flue gas (the chimney gas) at 220 to 310 degrees Celsius, boiler feed water at 30 to 35 degrees Celsius.
• Proposed: an economiser that preheats the feed water to 75 degrees Celsius.
• Energy saving potential: 5 to 8%. Simple payback: up to 8 months.
• The feed water rise is 75 − 35 = 40 up to 75 − 30 = 45 degrees Celsius. That is our arithmetic from the printed ends.

Who has one

TERI says some boilers in the cluster already have an economiser. It says boilers installed in micro and small units do not have a way to recover heat from waste gases. If your boiler is a micro or small unit’s, assume yours has none until you look at the chimney.

Check the number on your own boiler

• Read the flue gas temperature at the chimney base with a thermometer pocket or a flue gas test, before and after.
• Compare fuel bought per month for the same steam made, for the same months a year apart.
• Our general economiser page gives a rule of thumb from the flue gas drop. It is a separate method; use one or the other, not both stacked.

Example: a boiler burning 40 tonnes of wood a month

• Saving at 5%: 40 × 0.05 = 2 tonnes a month
• Saving at 8%: 40 × 0.08 = 3.2 tonnes a month
• At the survey’s wood or biomass price of rupees (Rs) 2,200 to 3,000 a tonne (the survey year is 2014-15): 2 × 2,200 = Rs 4,400 up to 3.2 × 3,000 = Rs 9,600 a month
• A year: Rs 52,800 up to Rs 115,200

Example only, at the survey’s prices, which are undated in the price table. Wood prices moved with moisture and season. Use today’s price from your invoices.

What Senseible does here

Senseible reads your fuel invoices into monthly records, so the fuel you bought in each month is easy to line up before and after an economiser. It does not read a boiler or its chimney, so the comparison rests on your own invoices.

• Green loan readiness check
• Boiler economiser: calculating the CO2 cut
• Panipat single pass or three pass boiler
• Panipat fuels and carbon

Sources: TERI, Energy Profile: Panipat Textile Cluster, 2016 (SAMEEEKSHA)

Last reviewed 2026-11-07. Figures are from the Panipat survey of 2014-15, published in 2016. The survey table prints each saving as a range with no boiler size, fuel tonnes or equipment cost. Check a current quote and your own fuel records before you rely on any payback.