László Heller

Heller László (19071980) was a Hungarian professor and mechanical engineer credited with inventing the Heller–Forgó dry cooling tower system for power stations.

Heller–Forgó system

The Heller–Forgó system is named after Heller and László Forgó (1907–1985), the active collaborator in the industrial implementation of the system.

Also known as the Indirect Dry Cooling System, it solved an important problem at power stations by utilizing cooling water more efficiently. The main point of their invention was to condense the vacuum steam using an injection of cool water. The still-warm water enters into the fine-gilled heat exchanger, cools down and becomes usable again for when the cycle is repeated. Installations include a water-cooled steam condenser, circulating machine groups, circulating water mains and a dry cooling tower which contains Forgó-type water-to-air heat exchangers. Heller's key achievement was to obtain the least condenser temperature for a given temperature of incoming cooling water by keeping the terminal temperature difference (TTD) as low as possible. The heat transfer between the working fluid and the cooling air is achieved by convection only and not by evaporation as in a wet cooling tower.

The firm set up by Heller and Forgo attracted attention from MDAX-listed GEA Group which held its shares from its privatization in 1992, until 2020 when the EGI firm was sold to Hungary’s monopoly power company, state-owned MVM Group.

In 2023 the system attracted the attention of some Iranian academics who were interested in the replacement of a wet cooling tower.

Awards, honors and legacy His grave in Kozma Street Cemetery, the biggest Jewish cemetery of Budapest. Asteroid 276975 Heller, discovered by Hungarian astronomer Krisztián Sárneczky at Piszkéstető Station in 2004, was named in his honor.