One of the most promising applications for active solar heating worldwide is the drying of agricultural products.

In a recent study, the potential amount of energy that could be displaced using solar in this market was estimated to be between 300 PJ and 900 PJ annually, primarily in displacing fuel-fired dryers for crops that are dried at temperatures less than 50C. The use of solar energy for these markets is largely undeveloped.

Wood and conventional fossil fuels are used extensively at present. In many countries, more expensive diesel and propane fuels are replacing wood.

Three key barriers to increased use of solar crop drying are

• the lack of awareness of the cost-effectiveness of solar drying systems,
• the lack of good technical information and
• the lack of good local practical experience.

The objective of the Task was to address the three barriers above by providing technical and commercial information and experience gained from the design, construction and operation of full-scale, commercially viable solar drying systems for a variety of crops and a number of geographical regions where solar is expected to have the greatest potential.

Crop grower and processor industry associations were key partners in dissemination of the results.