Solar energy has been around for thousands of years. The earliest forms of solar energy consisted of people using the sun to dry crops and grains. They would spread grain and fruit out in the sun after harvesting in order to dry the crops. The only problem to this method was that the crops were being subjected to damage by birds, rodents, wind, rain and contamination by windblown dust and dirt.
Solar Dryers
The simplest form of Solar Energy are Solar dryers, which consist of a shed or an enclosure, screened drying trays or racks, and a solar collector.
The southern side of the enclosure is usually glazed which allows sunlight to dry the material.
The interior of the enclosure is dark colored in order to absorb solar energy that will heat the air.
The air heated in the solar collector moves up through the material being dried either by natural convection, or is fan forced.
There are very few solar dryers in the U.S due to the high cost.
If the collectors were designed to be used at another time of the year, like to heat buildings, solar dryers would be more cost-effective and common.
Solar Heaters& Solar Water heaters
Livestock must be enclosed in temperature and air quality controlled buildings in an effort to promote animal health and growth.
The air inside these controlled buildings must be changed regularly to remove moisture, toxic gases, odors and dust.
Solar air heaters
can also be used to supplement natural ventilation during summer months. Heated water can
account for up to 40% of the energy used on a dairy farm.
Solar water Heating Systems are very cost-effective. They can heat water as well as provide water for cleaning, which will help reduce utility costs.
Solar Greenhouses
Greenhouses are dependent on the sun to supply their lighting necessities.
However, they do not rely on the sun for heat, but rather gas and oil heaters to maintain the necessary temperature during the colder months.
Solar Greenhouses on the other hand depend on the sun to supply light as well as heat to maintain the necessary brightness and temperature.
The greenhouses are positioned so that the southern side is glazed, receiving maximum exposure and the northern side has little to no glaze and is insulated.
Greenhouses have enough thermal mass that it can collect and store enough solar heat energy and insulation, that it retains enough heat to be used on rainy and cloudy days.
Photovoltaic Systems
Photovoltaic or Solar electric systems convert sunlight to electricity by using solar panels. On cloudy days PV systems can produce up to 80% of their potential energy. Potential consumers tend to worry about their solar panels being damaged, but there is no need to worry, being that designers test panels for hail impact, high wind, and freeze-thaw cycles representing year- round weather conditions. Professional installation and service is often included in the purchase price. PV systems maintenance is limited to visual checks and servicing batteries. PV systems are in fact very safe. They do not contain high voltages and they are not hazardous.
PV Water Pumping
PV Water pumping is one of the most cost-effective water pumping option, and is easy to install. It is most used in remote areas where there is no existing power line. PV water pumping is very cost-effective for remote livestock water supply, pond aeration, and small irrigation systems. The Solar water pumps work only when the sun is shining, mostly during the summer months, and water is stored in tanks to be used throughout the year. When it comes to supplying water to remote pastures, PV water pumping is the most cost effective system, and requires the least maintenance.
