How does the Bureau of Energy Efficiency (BEE) star label rate packaged boilers, and what does it mean for fuel use?
BEE launched a voluntary star label for packaged boilers on 1 March 2024, valid to 31 December 2026. Stars from 1 to 5 rest on thermal efficiency on a net calorific value (NCV) basis in percent. My advice, not release text: quoted efficiencies are only comparable if they use the same basis.
What the release says
- A packaged boiler is a factory-made, ready-to-use boiler for steam and hot water in process industries.
- One to five stars are awarded on thermal efficiency on the NCV basis in percent, with 1 star the minimum energy performance level.
- Scope: boilers manufactured, commercially purchased, sold or imported in India under Indian Standard (IS) 13979:1994.
- Voluntary phase, valid up to 31 December 2026. Check what applies from 1 January 2027.
- Expected: penetration of labelled boilers rising from 10 percent in 2024 to 100 percent in 2033, with cumulative savings of about 3.1 million tonnes of oil equivalent (TOE) and 7.23 million tonnes of carbon dioxide equivalent (CO2e) over 2024 to 2033.
Read a quote carefully
The programme rates on NCV, so ask any supplier which basis their efficiency figure uses and what fuel the test used. Two figures on different bases are not like for like. That advice is my reading and not text from the release. The release does not give the efficiency thresholds for each star.
What a few efficiency points are worth
For the same useful heat, fuel energy is useful heat divided by efficiency. The worked example below shows a 5 point step is worth about 6 percent of fuel.
Useful heat of 10,000 gigajoules a year (example)
- Boiler at 80 percent: 10,000 / 0.80 = 12,500 gigajoules of fuel
- Boiler at 85 percent: 10,000 / 0.85 = 11,765 gigajoules of fuel
- Saving: 12,500 minus 11,765 = 735 gigajoules, which is 735 / 12,500 = 5.9 percent
- With a fuel of 20 gigajoules a tonne (example only): 735 / 20 = about 37 tonnes of fuel a year
The heat demand, the efficiencies and the fuel heat value are examples. Use your own boiler records, and use the fuel value on the same net calorific value basis as the efficiency.
What Senseible does here
Senseible reads fuel invoices and electricity bills into monthly records, so your fuel use before and after a new boiler sits in one place.
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Last reviewed 2026-11-05. Scope, rating basis, standard, validity and projected figures are from the Press Information Bureau release of 1 March 2024. The thresholds per star are not in the release. The fuel arithmetic uses example inputs. The validity ends on 31 December 2026, so check the status with the Bureau of Energy Efficiency.