2.3 Improving Efficiency

HVAC&R equipment contributes greenhouse gases to the atmosphere in two ways: directly, through leaked or vented refrigerants, and indirectly, through electricity usage, with the latter representing up to two-thirds of GHG emissions.35

One way to reduce electricity usage and cut energy costs – and help the environment if the energy is powered by fossil fuels – is through proper maintenance of HVAC&R equipment. A white paper by the Clean Cooling Collaborative (formerly the Kigali Cooling Efficiency Program) estimates that better optimization, monitoring and maintenance of cooling equipment globally has the potential to save 30Gt of CO2 emissions by 2050.36

The efficiency of HVAC&R equipment can also be improved by investing in components designed to maximize performance like variable-speed drives, ECM fans and enhanced heat exchangers. For example, last year, Evapco, a major U.S. manufacturer of heat transfer products, introduced a new finned coil design, called the Ellipti-fin, which boosts thermal performance of closed-circuit coolers and evaporative condensers, improving efficiency by an average of 25%, the company said.37

The inclusion of a vapor quality sensor is the key to improving the efficiency of a low-charge ammonia DX (direct expansion) industrial system for low- and medium-temperature applications, according to Danish manufacturer HB Products.38 In addition, natural refrigerants, which already cut direct emissions due to their ultra-low GWPs, also typically boost the efficiency of a refrigeration or air-conditioning system.

Ammonia is widely recognized as a highly efficient refrigerant by itself and in concert with glycol or CO2. 39 Hydrocarbons like R290 also improve efficiency, while CO2 systems can operate with high efficiency in even warm climates when equipped with technology like adiabatic gas coolers, parallel compressors and ejectors.40

Last year, Italian component manufacturer Carel published a white paper on how to achieve the most efficient natural refrigerant systems that can optimize energy savings and reduce indirect CO2e emissions.41

Last December, 14 countries signed the Product Efficiency Call to Action, which aims to double the efficiency by 2030 of four priority products – air conditioners, refrigerators, industrial motor systems and lighting – that account for 40% of global energy consumption.42

Establishing the efficiency benefits of natural refri- gerants is a key way to drive adoption of natural refrigerant equipment. Ample evidence already exists that all natural refrigerants can deliver these efficiencies. Moreover, the efficiencies offered by natural refrigerants can be optimized over time via proper equipment maintenance and investment in efficiency-enhancing components.