A brewery outside Lisbon, Portugal. It is easy to picture cold beer, but inside the plant the dominant feature is steam. Pasteurising, heating, and cleaning all consume large volumes of high-temperature steam, and for decades breweries have burned natural gas to produce it. That familiar arrangement is now changing. Instead of turning up the gas, this plant is preparing to brew with solar power and a heat battery.
The heat inside a glass of beer
Brewing is more energy-intensive than most people assume. Before beer reaches a glass, it passes through several thermal stages:
- Fermentation — yeast requires a steady, controlled temperature
- Pasteurisation — heating is essential for shelf life and consistency
- Cleaning (CIP) — keeping large vessels sanitary consumes hot water and steam
Steam demand at a large brewery is therefore substantial, and it converts directly into fuel cost and carbon emissions.
Why solar alone falls short
Solar is the obvious first answer for a plant in a sunny country like Portugal. But there is a decisive obstacle.
The sun shines during the day; the brewery needs steam 24 hours a day.
At night or under cloud cover, intermittent generation can stall a production line. That is precisely why the electricity generated at midday has to be stored — as heat — and drawn back out when production needs it.
How the three partners structured it
Three companies came together to solve this: heat battery specialist Rondo Energy, Portuguese energy group EDP, and Heineken’s local operation, Sociedade Central de Cervejas.
The design is straightforward. Daytime solar electricity supplied by EDP heats Rondo’s specialised brick stack to very high temperature. After dark, that stored heat generates the process steam the brewery needs.
The Lisbon system is rated at 100MWh and is scheduled for full operation in 2027 — the largest heat battery project in the beverage industry, backed in part by the European Investment Bank.
What actually changes
| Gas boiler (conventional) | Solar + heat battery | |
|---|---|---|
| Energy source | Natural gas | Renewable electricity |
| Carbon emissions | Direct emissions from combustion | No direct emissions in operation |
| Fuel cost | Exposed to gas price swings | Uses low-cost daytime power |
| Round-the-clock supply | Yes | Yes, via thermal storage |
| Process changes | — | Same steam format, existing equipment reused |
| Regulatory exposure | Rising CBAM and carbon costs | Lower embedded carbon, lower exposure |
The last two rows carry most of the weight. A heat battery delivers steam in the same form the process already uses, so the production line does not have to be redesigned. At the same time it cuts the carbon embedded in the product, easing the regulatory burden.
Why this case matters
A brewery that burned gas for steam for centuries is preparing to run on sunlight and stored heat. That is more than one plant’s cost-saving exercise — it shows how industrial process heat, long treated as the blind spot of decarbonisation, can change.
For background on why industrial process heat is so hard to decarbonise, and where thermal storage fits in, see the companion piece below.
Conclusion
Climate targets will not be met by building generation alone. What determines industrial viability is how intelligently we close two gaps: between day and night, and between electricity and heat. The Heineken project shows that the technology for closing them has moved into commercial deployment.
GIGAette is developing solutions in this direction — storing and delivering heat at the steady temperature industrial processes actually require.
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