Industrial heat pumps: a buyer’s guide for Indian plants
An industrial heat pump makes hot water for a factory from electricity, at a fraction of the energy a boiler burns. It does not burn anything. It moves heat from a cooler source, such as air or a warm water stream, and lifts it to the temperature the process needs.
We wrote this guide for a plant engineer or owner deciding whether one fits. It covers what the machine does, which loads it takes, what it saves, and what to check before asking for a quotation.
What does an industrial heat pump do?
It works like a refrigerator in reverse. A refrigerant takes up heat at low temperature, a compressor raises its pressure, and the heat comes out at a higher temperature. The compressor uses electricity, and the heat delivered is several times that electricity.
That ratio is the coefficient of performance, or COP. It depends on the gap between the source and the output temperature. A smaller gap gives a higher COP.
Which factory loads suit one?
The machines covered here make hot water up to 120°C. That covers a large share of factory heat, because many processes need hot water, not steam.
| IndustryLoads in range | |
| Food and dairy | HTST pasteurisation at 72 to 75°C, CIP caustic at 70 to 85°C |
| Hotels and hospitals | Guest hot water at 45 to 70°C, laundry at 60 to 85°C |
| Automotive | Alkaline degrease at 55 to 80°C, phosphating at 50 to 60°C |
| Pharmaceutical | Purified water loop sanitisation at 80 to 95°C, HVAC reheat |
| Chemical | Aqueous jacketed reactors up to 88°C |
Loads above that range stay on steam or direct firing. Examples are retort sterilisation at 121°C, paint ovens at 140 to 200°C, and resin reactors at 200°C and above. A good supplier names those loads plainly and leaves them out of the proposal.
What does it save, and against which fuel?
The saving depends on the fuel the heat pump replaces. Here is the cost of one useful kilowatt hour of heat, from 2026 prices:
| Heat sourceCost per useful kWh | |
| Light diesel oil | ₹12.58 |
| Furnace oil at ₹71.99 a kg | ₹7.70 |
| Industrial PNG in Gujarat at ₹68 a standard cubic metre | ₹7.24 |
| Heat pump at COP 3.5, Maharashtra HT-I tariff | ₹2.41 |
| Delivered coal at ₹6,000 a tonne | ₹1.94 |
Against gas, furnace oil, LDO and diesel, the heat pump wins clearly. Against delivered coal it does not, on grid power. A coal-fired plant switches for compliance, air quality and labour, not for fuel cost. The boilers assume 85% efficiency for gas and 80% for oil.
Why output temperature matters most
COP falls as the output temperature rises. Tetra Heat Pump water source units reach COP 4.5 to 5.2 at 60°C output. Measured Indian performance is about 2.26 at 110°C and about 2.0 at 120°C.
So one site can have two very different projects. A 60°C wash-water duty and a 120°C process duty are not the same machine. They should not be quoted as one.
Air source, water source or cascade?
The source is the other half of the decision.
- Air source takes heat from ambient air. It suits a site with no warm stream to use.
- Water source takes heat from a warm stream the plant already rejects, such as condenser water. It gives the highest COP.
- Cascade puts two refrigeration circuits in series. It reaches high output temperatures from a cold source.
The industrial heat pump systems page sets out all three configurations side by side.
How long does it take to pay back?
Indian buyers usually ask for a payback of one to three years. A World Bank study of 224 Indian MSMEs found a realised payback of 44 months. Treat one to three years as a screen, not a rule.
The payback rests on four numbers: the fuel price today, the electricity tariff, the hours the load runs, and the COP at the output temperature. A supplier who gives a payback without all four has guessed.
What to check before you buy
- The output temperature at your duty, not the machine’s maximum.
- The COP at that temperature, with its source temperature stated.
- The heat source, and whether a warm stream on site can feed it.
- The electrical load it adds, and whether the sanctioned load must rise.
- Integration with your controls, such as a BMS, SCADA or PLC network over Modbus or BACnet.
- Service response, and who attends a breakdown.
For scale, Tetra Heat Pump’s industrial range runs to 1,450 kW in a single unit, and to 5 MW in a multi-unit project.