Solar cooling: A solar solution to energy problem

Research has shown that the highest incidence of solar radiation in the world occurs in Australia, making solar energy the country’s most accessible source of natural and renewable energy. During the summer months temperatures can sore and with the increasing trend to install air conditioning in new and retrofit builds, air conditioning units are estimated to make up 7% of residential electricity consumption. The cooling and heating of commercial and domestic residences in Australia consumes around half of a building’s energy needs, while air conditioners account for a staggering fifty per cent of the power generated by the nation on its hottest days.It is with this in mind that Australia's Commonwealth Scientific and Industrial Research Organisation (CSIRO ) and industry groups, such as the Australian Solar Cooling Interest Group (ausSCIG), are researching and developing solar cooling technologies aimed at reducing energy consumption and greenhouse gas emissions.

What is solar cooling?

Solar cooling is a technology that uses energy produced by the Sun to power a thermally driven cooling process, which generates chilled water or conditioned air for use in applications such as building air conditioning systems. Unlike cooling systems in commercial buildings, cooling in residential applications rarely uses chilled water.

There are several types of thermally driven cooling techniques including desiccant cooling, adsorption chillers, absorption chillers and ejector refrigeration. The process of desiccant cooling uses chilled water, or a solid desiccant material, as a refrigerant to dehumidify air before recycling it around a system.

The majority of conventional air conditioners use electricity derived from fossil fuels. CSIRO understand the importance of reducing the amount of electricity required to power air conditioning systems, especially during peak demand, and are using their expertise to develop solar cooling techniques specifically focussed on cooling Australia’s homes, including rural areas with limited access to electricity.

CSIRO solar cooling research and development

CSIRO engineers are in the process of developing a new generation of desiccant solar cooling systems with increased efficiency and reduced capital cost. The research includes the development of new desiccant materials that increase dehumidification and reduce declines in pressure. CSIRO, in turn, intend to improve integration of these innovative systems into commercial and residential buildings.

The irony of the situation is that Australia’s sunny climate is both the cause and the solution to this significant environment problem. However, developments in solar cooling technologies will only be able to be correctly and effectively implemented if social awareness is raised and social and economic factors are addressed by the government.

For more information about the research and development being carried out by CSIRO, please visit the website.

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