5 heat transfer trends for energy efficiencies in residential and commercial cooling applications
Our built environment is currently the world’s single largest contributor to greenhouse gas emissions. In Australia, where the Green Building Council of Australia (GBCA) launched the Green Star certification in 2003, developers and builders have long been thriving to improve the energy efficiency of commercial constructions.DATE 2022-02-03
Achieving high environmental ratings is not only seen as a sustainability value but in the eyes of financial institutions and investors, reduces exposure to commercial risk and asset obsolescence by ensuring assets are future-ready (Source: GBCA Introducing Green Star)
Yet, many building projects don’t fully accommodate for the performance of components within the cooling system to achieve those ratings and other energy efficiency benefits as required in tender documents.
Let’s examine the role of heat transfer – a key technology that allows the recovery and re-use of energy, thus reducing your carbon footprint and also operating costs.
1. From shell-and-tube to plate heat exchangers
Heat recovery can be increased substantially by exchanging existing shell-and-tubes for compact heat exchangers. Plate heat exchangers weigh less than 1/16th of the total weight of shell-and-tube exchangers and use 1/10th of the floor space. Plate heat exchangers are up to five times more efficient than shell-and-tube designs with approach temperatures as close as 1°C. The result is more energy being put back to use, energy that would otherwise have gone to waste.
2. Trend towards heat pumps
While heat pumps have been gaining popularity in residential buildings for a number of years, they are also now becoming more common in the commercial sector for HVAC, refrigeration, space heating, pool heating and cooling and hot water applications. A correctly designed heat pump system should reduce overall energy consumption. The heat exchanger is an integral part of this system, especially when designed in conjunction with the overall COP (co-efficient performance) of the plant.
3. Low GWP refrigerants
Legislative changes and import caps mean the industry is moving towards low global warming potential (GWP) refrigerants. Heat exchanger technology has to deal with the different characteristics of these new gases. Alfa Laval has developed very specific heat exchanger product designs to address the challenges of these current and new low GWP refrigerants. For example, the Alfa Laval DynaStaticTM distributor is a key feature in the inlet to improve the evaporation of R32 and other new refrigerants.
4. Certifications matter
Designing for energy efficiency is more important than most people think, and certifications are one way to guarantee performance. A correctly designed heat exchanger in a cooling tower allows you to save a significant amount of energy. In an incorrectly sized differential, every 0.3 degree difference is a sacrifice of a cost of 1.25KW per second passing through the heat exchanger. Alfa Laval plate heat exchangers are certified to the world’s most recognised standard, which is the AHRI (Air-Conditioning, Heating, and Refrigeration Institute) certification.
4. Data centres set new standards
Data centres have long set the standards in terms of energy efficiency ratings for commercial buildings in Australia, but even there, greater PUE (Power Usage Effectiveness) can be achieved by optimising cooling systems and designs. The use of AHRI certified heat exchangers negates the need for external testing, which saves time and gives you guaranteed performance. Immersion technology is another trend to watch, as cooling requirements continue to increase in this growth industry.
5. Take energy savings further with waste heat recovery
In any operation, there is almost always room to continue reducing power consumption and related costs. The secret is in reclaiming the energy lost as exhaust gas heat and using this in areas such as hot water generation in areas like hospitals, laundries or other process lines. As the pioneer in waste heat recovery, Alfa Laval has the technology and expertise to help you further increase your energy efficiency with the Micro exhaust gas economizer.
Meet the experts
Alfa Laval Australia’s Colin Ellis and Suria Moodley help customers optimise their HVAC&R systems for performance and energy efficiencies with the latest heat exchanger technologies.
Webinar on-demand: Learn how to design your heat exchanger for new refrigerants
The shift to low Global Warming Potential (GWP) refrigerants is gaining momentum globally. Join this webinar to upskill yourself on the design requirements for GWP refrigerants - to build systems that are energy-efficient, durable and compliant, even under the highest pressure.