World premiere: BITZER EXPANDER unit subcools without any additional electrical energy

Nuremberg/Sindelfingen, 16.10.2018. BITZER is presenting a world premiere at this year’s Chillventa: with the BITZER EXPANDER subcooling unit, the specialist for refrigeration and air-conditioning technology makes CO₂ refrigeration systems over 20 per cent more energy-efficient – both in retrofits and new systems. An EXPANDER unit prototype will be on display at BITZER trade fair stand 326 in Hall 7 from 16 to 18 October 2018.

BITZER has developed a component that boosts efficiency specifically for supermarkets and logistics specialists in the form of the EXPANDER: at an ambient temperature of 32°C, it increases a standard booster system’s cooling capacity at the design point by more than 20 percent. In seasonal terms, for example, energy savings of up to 17 per cent are possible in a parallel system in warm climates. A single-component retrofit can thus increase cooling capacity for transcritical CO₂ systems. Installation is quite simple and there’s no need to redesign the refrigeration system, which can be a complex process.

Reduced system complexity

Thanks to the EXPANDER unit, CO₂ can now also be used more efficiently in hot climates. The new BITZER development is suitable for both retrofitting existing systems and designing new ones. Combined with BITZER ECOLINE+ reciprocating compressors, for instance, the EXPANDER unit represents a premium solution for outstanding eco-efficiency and optimised energy efficiency for transcritical CO₂ systems. The EXPANDER unit works much like classic external subcoolers. The internal subcooling unit comprises a control valve, a heat exchanger and the heart of the system: an expander-compressor unit. The EXPANDER unit relaxes the primary mass flow, whilst the energy generated in the same unit compresses the subcooler mass flow and feeds it back before the gas cooler – without any additional electrical energy. Thanks to the compact dimensions and simple mounting behind the gas cooler, the unit can be easily and affordably integrated into many different CO₂ systems.

An important partner in the development of the BITZER EXPANDER unit is ALDI SÜD. The well-known food retailer already boasts climate-neutral operations and is always making every effort to improve its carbon footprint, which is why the discount supermarket will be testing the first subcooling units in its chain stores. Already today ALDI SÜD is increasingly using refrigeration systems with BITZER reciprocating compressors for transcritical CO₂ applications, exploiting many options for energy savings.