Growing populations and improving economies world-wide, especially in the developing world, are projected to lead to huge increases in global demand for space cooling, dehumidification, and refrigeration. This will make reaching global energy and climate goals extremely challenging. In order to address this, what actions can the global HVAC&R community take to reduce the impact of this demand growth?

Within the recently approved HPT Annex 53, two possible technology paths are under investigation:

  • Advanced vapor compression with low or ultra-low GWP refrigerants;
  • Non-traditional technologies (zero-GWP).

No single technology is a clear winner for air-conditioning or refrigeration in all applications. Vapor compression technology has had decades of RD&D to date, and this is continuing. It may continue to be the system of choice, especially for the near term, and possibly for the long term as well. However, vapor compression is vulnerable to further refrigerant restrictions.  Non-traditional technologies generally are not subject to this challenge, since they do not rely on refrigerants in the traditional sense. On the other hand, these technologies generally need further development in order to be ready for the market.


The objective of Annex 53 is to develop technology solutions for higher efficiency air-conditioning/refrigeration systems to help minimize/reduce projected energy consumption increases. The main technology focus areas are traditional vapor compression, alternative vapor compression approaches, and non-traditional cycle approaches for AC and/or refrigeration applications. The Annex scope is broad, but the challenge is also huge; it is not likely that there will be only one, or a few, “right” solutions.


Field News

Annex 53 Kick off at the ASHRAE Meeting

To start up and introduce their new Annex 53 “Advanced Cooling / Refrigeration Technologies Development” the Annex 53 team will...