Greenhouse, drying, pool – where miner waste heat is needed all year

Space heating runs for half the year. A miner should run all year. So it fits best with consumers that take no summer break.

Greenhouse

• Demand: high from autumn to spring, at night in summer too.
• Cooling type: air for simple frost protection, hydro for pipe heating at ground level.
• Watch out: Greenhouse air is humid. An air-cooled unit must get dry intake air from outside and may only blow its warm exhaust air in, not draw in the humid air.

Drying

Timber, hay, grain, wood chips or paint rooms need large volumes of warm, dry air.

• Demand: all year or at harvest time, depending on the material, but then around the clock.
• Cooling type: air. A miner's exhaust air at 30 to 60 °C is exactly what a drying process needs.
• Watch out: dust. The miner's intake air needs a filter, and the exhaust air must not recirculate.

Pool and swimming pool

• Demand: a heated pool loses heat constantly, outdoors especially at night. Indoor pools need it all year.
• Cooling type: hydro. Pool water wants around 28 °C, which every hydro miner achieves at a low chip temperature and therefore good efficiency.
• Watch out: Pool water contains chlorine and chlorides and attacks many heat exchangers. A heat exchanger that its manufacturer approves for swimming pool water belongs between the miner circuit and the pool: titanium for salt water or salt electrolysis, while for normally chlorinated fresh water stainless steel is enough, depending on the manufacturer.

Hot water in hotels, sports facilities and businesses

• Demand: daily and regardless of the season.
• Cooling type: hydro with a model that allows high outlet temperatures.
• Watch out: In larger drinking water systems, the hot water must leave the water heater at 60 °C at all times to prevent legionella. If the miner cannot do that, it preheats the water and a second heat source brings it up to temperature.

Hall and workshop

• Demand: only in the heating season.
• Cooling type: air, straight into the room.
• Watch out: In summer the exhaust air has to go outside. Plan both air paths from the start.

How to choose

Work out how many hours a year your consumer really takes the heat. An indoor pool and hot water reach almost 8,760 hours, hall heating less than half of that. The higher this number, the larger the share of the electricity costs that you no longer have to pay to another heat source.

Sources

• Umweltbundesamt: hot water temperatures in large systems under DVGW W 551 (PDF)
• Bowman: heat exchangers for swimming pools, materials and sizing (PDF)
• VAU Thermotech: brazed plate heat exchangers in swimming pools (PDF)

As of October 2026. A specialist contractor sizes the heat exchanger and the drinking water system; this article does not replace one.