Solar Energy Perspectives - IEA

Solar Energy Perspectives: Industry and transport
Photo 5.2 Passive solar dryer for coffee beans in Costa Rica
Source: Solar Wall.
Key point
Solar air drying helps preserve crops where refrigeration is lacking.
Evaporation is a form of drying and both involve a volatile component changing phase
through the input of energy. Applications can mainly be found in the food industry and
chemical industries.
Pasteurisation and sterilisation need heat of 75°C and 105°C respectively. In food industry
and biochemistry there are numerous applications. With liquids, pasteurisation can be
performed in heat exchangers, but for solids (cans or jars), a heat-transfer medium such as
water, air or steam is required.
Preheating boiler feed water is another possible application for solar heat in the process
industry. Since this is a low-temperature heat sink, solar energy is suited very well, but there
might be other, less costly heat sources available for this process.
Heating of production halls is necessary in many countries in wintertime. Although heating
is not purely an industrial application, special challenges might arise from using the heat
supply system for both processes and space heating.
Solar cooling with absorption systems is a very special application of solar heat in industry.
Integrated into the whole energy system of the industrial plant, it might offer special
opportunities in the food industry, for instance.
Most of the process heat in the medium range from 100°C to 200°C is used in the food, textile
and chemical industries for such diverse applications as drying, cooking, cleaning, extraction
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© OECD/IEA, 2011