MT Innovation, an Italian research and development company, has developed a prototype mobile air-conditioning (MAC) unit for camper vans using an ammonia-water (R717-R718) absorption system. The unit provides 3kW of cooling and 6kW of heating capacity, consuming significantly less electricity than traditional camper van MAC systems. It can also supply domestic hot water.

The system is designed with a modular structure, separating the fluid supply circuit from the refrigeration section, making it adaptable to different vehicles. The prototype measures 60 × 40 × 35 cm and weighs less than 30kg, with the production version expected to be 30% smaller.

The ammonia-water absorption cycle operates by using ammonia as the refrigerant and water as the absorbent. Heat input, which can be sourced from waste heat in gas-powered vehicles or a small burner using gasoline, hydrogen, or natural gas, drives the cycle. MT Innovation patented the unit in 2020 and received funding from the Italian Ministry of Economic Development in 2021. A working prototype is set to be presented to companies in September 2024.

Ammonia-water absorption technology has not previously been applied in MAC systems, but the use of natural refrigerants in the sector is increasing.