# Data centre heat is factory heat: the one-loop model

> A data centre turns nearly every kWh it draws into warm water and pays to throw it away; a factory next door burns fuel for the same temperatures. One loop — green electricity in, heat pumps on the return water, heat out, both sites metered — and what it is worth.

Canonical: https://joulewise.com/insights/data-centre-heat-is-factory-heat  
Publisher: jouleWise Advisory Services Pvt Ltd, Noida, India · Spain  
Reviewed: 2026-10-08  
Status: company page

## In short

A 10 MW IT hall is about 14 MW at the meter at a PUE of 1.4, round the clock, mostly on grid electricity today. Almost every kWh the servers use ends up as low-grade heat in the cooling water, and the data centre then pays again — in chiller electricity and cooling-tower water — to reject it to the air. India's data-centre capacity is projected to grow to roughly 6.5–12 GW by 2030 on industry estimates, and each MW of IT load releases about a MW of heat, continuously. Often a few hundred metres away, a factory burns piped natural gas, coal, LPG or diesel in boilers for hot water, washing, CIP, drying and jacket loops, mostly below 120 °C. That fuel is its Scope 1 line, the hardest carbon to cut and the most exposed to price swings, and CBAM, BRSR Core, CCTS and customer programmes now ask for metered evidence of cutting it.
*Published 2026-10-08 · Data centres · the loop*

## Two neighbours, two wasted bills

A 10 MW IT hall is about 14 MW at the meter at a PUE of 1.4, round the clock, mostly on grid electricity today. Almost every kWh the servers use ends up as low-grade heat in the cooling water, and the data centre then pays again — in chiller electricity and cooling-tower water — to reject it to the air. India's data-centre capacity is projected to grow to roughly 6.5–12 GW by 2030 on industry estimates, and each MW of IT load releases about a MW of heat, continuously.

Often a few hundred metres away, a factory burns piped natural gas, coal, LPG or diesel in boilers for hot water, washing, CIP, drying and jacket loops, mostly below 120 °C. That fuel is its Scope 1 line, the hardest carbon to cut and the most exposed to price swings, and CBAM, BRSR Core, CCTS and customer programmes now ask for metered evidence of cutting it.

## The loop, in five steps

Green electricity first: a portfolio built to the data centre's flat 24×7 shape — ISTS and intrastate wind–solar hybrids, rooftop solar, a battery for the evening, green-market purchase for the gaps — with open access approvals, ABT metering and scheduling handled. Then the heat: warm return water from the CRAHs, CDUs or condensers passes through an isolation plate heat exchanger, so the data centre's water never leaves its own loop and nothing changes inside the white space. Industrial heat pumps lift that heat to 70–90 °C hot water, or low-pressure steam to 120 °C, and send cooler water back, so the chillers and towers do less work.

A hot-water store — about 400 m³, or 13 MWh-th, in the worked example — is charged in the cheapest solar blocks and drawn on the factory's shift pattern, with the boilers moved to standby for peaks and the duties above 120 °C. ergOS runs both sites on one screen every fifteen minutes; esgOS allocates electricity, heat and green attributes across the two companies at a metered boundary.

## Why the return water is such a good source

A heat pump's COP depends on the lift between source and delivery. Ambient air at 30 °C to 80 °C is a 50 K lift and a COP near 3.5. Chilled-water loops return at 20–30 °C, a similar lift with the bonus that heat is taken out before the chillers, cutting their electricity directly. Liquid-cooled and AI racks return at 40–50 °C by design, a lift of about 35 K and a COP of around 4–4.5 — which makes them the best heat source on any industrial site.

At the base-case COP of 3.5, one kWh of electricity plus 2.5 kWh from the loop gives 3.5 kWh of factory heat plus 2.5 kWh of cooling the data centre no longer has to buy: about 6 kWh of useful heating and cooling per kWh of electricity.

## What it is worth, illustratively

For a 10 MW IT data centre and a factory averaging 5 MWth at 80 °C over about 8,000 hours a year: 40,000 MWh-th of heat delivered from 11,430 MWh of green electricity and 28,570 MWh-th taken out of the loop. Fuel cost today on a PNG boiler, about ₹24.9 crore; heat-pump energy at ₹5.50 per kWh green, about ₹6.3 crore; energy-cost saving before capex and O&M, about ₹18.6 crore a year, with about 8,800 tonnes of Scope 1 CO₂ avoided. For the data centre, up to about 5.7 GWh of chiller electricity and about 40,000 m³ of cooling-tower evaporation a year avoided where the heat would otherwise go through wet towers.

Per kWh of useful heat: diesel about ₹10.59, gas about ₹6.22, a heat pump on DISCOM electricity about ₹2.43, on the loop with green open access about ₹1.57, in solar blocks with a store about ₹1.14. Illustrative only; every figure is replaced with metered site data in the baseline.

## Uptime first, and why one provider

No data-centre operator will trade uptime for heat revenue, so the energy centre is designed as an extra heat sink on the loop that can drop out at any moment without the data centre noticing: hydraulic isolation at the boundary, towers and dry coolers kept N+1, an automatic three-way bypass, the factory boiler on hot standby, the battery ahead of the diesel generators, and custody-grade heat meters on both sides of the exchanger.

Bought in pieces — a renewable developer, a chiller OEM, a boiler vendor, separate BMS and SCADA, an ESG consultant once a year — the interface between the two companies belongs to nobody. The one-loop model exists because electricity, heat, the metered boundary, the fifteen-minute dispatch and the carbon proof for both sites have to be one contract. Data-centre heat reuse operates abroad, mainly into district heating in Northern Europe; the claim here is the integrated single-provider model for an Indian data centre and a colocated industrial heat user.

**Try it:** [Size the loop in Data Centre Loop Studio](https://joulewise.com/studios/dc-loop)
## Questions and answers

**How much heat does a data centre produce?**  
About a MW of heat per MW of IT load, continuously; a 10 MW IT hall draws roughly 14 MW at the meter at a PUE of 1.4.

**What temperature can a heat pump reach from data-centre return water?**  
Hot water at 70–90 °C, or low-pressure steam to 120 °C at a lower COP. From a 40–50 °C liquid-cooled loop the lift to 80 °C is about 35 K and the COP about 4–4.5.

**Is the data centre's uptime at risk?**  
No. The energy centre is a parallel heat sink behind an isolation heat exchanger and an automatic bypass; existing heat rejection stays N+1 and the DC supply temperature is the controlling limit.

## Related

- [Size the loop in Data Centre Loop Studio](https://joulewise.com/studios/dc-loop)
- [Data centre heat loop](https://joulewise.com/solutions/data-centres)
- [Why temperature lift sets the cost of heat](https://joulewise.com/insights/temperature-lift-sets-heat-pump-cost)

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