Going natural with refrigeration energy.(The Open Door)

The title of a song--"Everything Old is New Again"--seems to fit the current state of the refrigeration and refrigeration research segment of the appliance industry.

To protect the ozone layer and minimize global warming, engineers and designers are again touting the praises of natural refrigerants--carbon dioxide, ammonia, and even air and water. The return to these natural refrigerants protects the ozone layer, and because they have a higher efficiency, it helps to decrease the greenhouse effect of fossil fuels used in energy production. This also helps to preserve the energy reserves of planet Earth for future generations.

This is making refrigeration equipment that is earth-friendly in emissions and energy consumption, as well as co-generation applications to provide additional energy and refrigerated storage facilities with a low initial cost and technological match with the location's infrastructure--a priority among the HVAC/R technical community.

However, alternate refrigerants for small facilities that approach the effectiveness of ammonia need to be utilized and/or developed. The efficiency and reliability of refrigeration systems and equipment must continue to be a priority.

Ultimately, we must seek ways to develop closed systems that are both easy to operate and maintain, and also cheap to build. Like the harvest of crops wasted because of gaps in the cold chain, the waste heat given off by refrigeration systems dissipates uselessly into the atmosphere during the refrigeration cycle. Further research and development in cogeneration can enable refrigeration plants to help pay their own way by providing mechanical or electrical energy to their users. Waste heat from power generation can even be used in the absorption cycle. This means creative, practical thinking is needed to use all the sources of energy--not just the obvious ones.

However, there are obvious areas for improvement such as the standard vapor-compression cycle, heat exchangers, frequency-controlled fans, adjustable-speed drives, automatic air purgers, and the use of computers and electronics for system design, monitoring, and control.

In fact, some of the ways to improve efficiency are so apparent that they are sometimes overlooked: improved operation and maintenance, hot gas instead of electrical resistance for defrost, use of desiccant dehumidification to supplement conventional cooling systems, and better insulation.

Efficiency combined with good operation and maintenance cannot be underestimated. A 2,000-sq-ft restaurant will decrease its power usage by approximately 30 percent annually by just doing things such as maintaining clean cools, maintaining door seals, loading items quickly, and not allowing cold items to warm up before loading them into a refrigerator.

Even as little as a 1-percent improvement in the energy efficiency of Canada's installed refrigeration capacity would save 4 million gigajoules of energy a year--the equivalent of 650,000 barrels of oil. Energy-efficient systems will benefit the world by reducing the amount of carbun dioxide produced, which reduces the potential for climate change; by reducing the amount of energy consumed, forestalling the depletion of the Earth's energy reserves; and by reducing the cost of running equipment, making refrigeration more manageable for developing countries to further raise their quality of life.

Refrigeration needs to be revitalized to be able to serve the needs of the world. We need to seek the best in refrigerants, efficiency, cost reduction, reliability, and energy utilization for all forms of refrigeration: industrial, transport, and domestic.

The art of refrigeration and HVAC has contributed to the comfort, safety, and health of the world. It has enabled people to live in inhospitable climates, explore the reaches of space, and combat diseases throughout the world.

We know the world will be a very different place in 50, 100, or 200 years. Will there be any fossil fuels left? Will end fusion become a reality? We are able to guarantee one thing--that people will continue to be comfortable enough to dream of the future, that is, if we continue to work on technology to make the future more energy efficient and continue using more usable, natural sources of refrigerants.

About the Author

Ron Vallort, P.E., is the current president of the American Society of Heating. Refrigerating and Air-Conditioning Engineers (ASHRAE). He is also president of Ron Vallort and Associates Ltd. in Oak Brook, IL, U.S. Mr. Vallort has a B.S. and M.S. in Mechanical Engineering from the University of Illinois in Urbana-Champaign, IL, U.S. He also is past chair of the International Association of Cold Storage Constructors and the International Institute of Refrigeration.

COPYRIGHT 2004 Dana Chase Publications, Inc.

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