Food Quality Magazine
ISSUE 01 | JANUARY 2016
Solar AiR Marks for the Food Industry
Victoria Hollick, Solar Air Heating World Industries Association,
Conserval Engineering (SolarWall®)
The benefits of using solar energy in
the processing of food products is gaining traction in both the agricultural
community and with end-use consumers who ascribe a premium to such
products.
Solar air heating systems are used in
different configurations around the
world to produce hot air that can be
used for space heating or for process
heat purposes. This specific use – solar process drying - is becoming more
popular in the agricultural community as it provides a clean energy solution to producing high quality food
products.
Consider that 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 air heating
into a drying operation produces a
double-benefit in terms of improving
both the process of drying and the
final product. The solar technologies
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.
Typically solar air heating systems
operate as a pre-heat to traditional
mechanical operations where it can
be easily incorporated into tunnel,
16
trough or conveyor dryers.
In both cases it substantially reduces
the dependency on traditional fuels
which has a myriad of positive effects, including:
of their products the Solar Air Heating World Industries Association
(SAHWIA) embarked on a program of
creating the “Solar AiR Logos” which
were unveiled in December 2015.
• 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
Solar air heating systems may also
reduce or eliminate poly-aromatic
hydrocarbons (PAHs) created by displacing conventional fossil fuels used
in active drying systems.
Solar air heating systems have been
used on hundreds of agricultural and
animal buildings for poultry ventilation, hog ventilation, and other
forms of livestock ventilation. Animal barns not only need to maintain
a very warm indoor air temperature
(up to 30 C is common), but they
also require continual ventilation air.
This typically produces enormous
heating bills, especially considering
that many farms and nurseries use
prop