Many of the world’s most important crops need to be dried to remove moisture as part of the production process. Removing the moisture from crops such a coffee beans, tea leaves, cocoa, nuts, fruit, rice, spices, corn, etc. is an essential process that helps transform the raw goods into the final product. It is also extremely resource intensive when using mechanical drying methods that rely on wood, propane or oil.  In more traditional drying operations, it is common for produce to be passively air-dried in the sun, which takes significantly longer than mechanical drying and can lead to a higher rate of spoilage, mycotoxins and uneven moisture levels.

Incorporating solar into a drying operation produces a double-benefit in terms of improving both the process of drying and the final product.

The SolarWall technology can heat large volumes of incoming air up to 55°C  (100°F) above ambient, making it ideally suited for many crop drying applications.  The solar air heating system may provide all of the heat during a sunny day or act as a pre-heat during cloudy conditions. It can either act in a standalone capacity via our modular SolarWall system, or as a pre-heat to traditional mechanical operations where it can be easily incorporated into tunnel, trough or conveyor dryers.

In both cases it substantially reduces the dependency on traditional fuels which has a myriad of positive effects, including:

  • lower operating costs;
  • decreased reliance on fuels that need to be transported to remote sites;
  • counteracting deforestation by reducing the quantity of trees that are harvested for fuel;
  • lower humidity in the incoming air (because it is heated before entering the building or drying chamber) which means that the air has been preconditioned to absorb more moisture;
  • GHG emission reductions; and
  • producing a high quality finished product that is eco-friendly and was processed using “clean & green” energy

Proper drying is also associated with a decreased incidence of mycotoxins, especially on corn (maize) and other crops. Adequate drying of crops is essential to help minimize the risk of mould growth and mycotoxins after the harvesting of crops, and solar drying is considered to be an effective preventative measure against mycotoxins.

SolarWall systems may reduce or eliminate poly-aromatic hydrocarbons (PAHs) created by displacing conventional fossil fuels used in active drying systems. As countries around the world embrace the principals of organic agriculture and sustainable production, they are also looking at how their food is processed and if it is safe and eco-friendly.

For products or processes that require higher temperature heat, SolarWall systems can still act in a pre-heating capacity and displace a percentage of the total heating costs.

Each square meter of SolarWall system produces the same amount of heat generated by a 500 watt heater. By installing a solar air heating system, burners not only get turned down, they often get turned off completely for extended periods of time.

Every client can tell such a story – and   every client is enjoying substancial energy savings. For instance, the Sanoma Herb Exchange California saves 31 million BTUs annually by displacing 325 gallons of propane that would be needed if fossil fuels were used instead of solar power. Keyawa Orchards, which dries over 12 million lbs. of walnuts every year, enjoys fuel savings of 1,431 million BTUs a year, with corresponding annual cost savings of $13,800. Coopeldos R.L.; a coffee installation in Costa Rica is enjoying annual savings of 25%. And on it goes.
As a result, the same technology that lets the SolarWall technology lead the way in using solar energy to heat buildings is now setting solar crop drying and solar process heating standards worldwide for both agricultural and commercial applications.






AMRtechnologies Inc. Solar & Electrical Systems
Tel: (+506) 7037-8077 or Toll Free: 1(800) 2130227
Solar Systems in United States & Latin America