Alfa Laval Kathabar – Consistently perfect

Alfa Laval Kathabar Twin-cel

Total energy recovery systems

How it works

More than 60% of a building’s energy usage is related to HVAC. With efficiencies up to 70%, the Alfa Laval Kathabar twin-cel energy recovery system exchanges temperature and humidity between ventilation and building exhaust air via a biocidal desiccant transfer solution. In each twin-cel section, the desiccant solution passes through high efficiency packing where it contacts the airstream.

In the summer, the warm, moist ventilation airstream is cooled and dehumidified by transferring energy to the relatively cool, dry building exhaust. In the winter, the cold, dry ventilation air is heated and humidified by the relatively warm, moist building exhaust. The difference in enthalpy between the building exhaust air and the entering ventilation air is key in the twin-cel energy recovery process.

Each system is optimized for energy efficiency. When possible, existing exhaust streams are harnessed to power the regeneration process.


  • Total energy (enthalpy) recovery – recovers both sensible (temperature) and latent (moisture) energy from the exhaust airstream; system typically recovers more than twice as much energy as sensible devices (air-to-air exchanger and runaround coils). 
  • Utility savings – system reduces heating and cooling energy up to 70%, and deceases carbon footprint.
  • Large capacity range – single unit sizes available up to 84,000 CFM, and multiple supply exhaust units can be coupled to accommodate to larger airflows.
  • Winter humidification without humidifier – consistent supply of temperature and humidity all winter; system only requires the use of a small water makeup line, and eliminates the concern of mold and bacteria due to biocidal desiccant.
  • Flexible equipment configurations – system can be configured to use multiple exhaust systems to feed a single supply, or vise versa.
  • No microbiological cross-contamination/cross leakage – supply and exhaust airstreams never come in contact with each other; biocidal desiccant scrubs ventilation air and exhaust of airborne bacteria, viruses and mold.
  • Industrial FRP (fiberglass) construction – long equipment life and reliability.
  • Comfort control – control temperature and humidity while improving indoor air quality.