Apr 10 2012
This article shows the future of solar energy in Africa by providing cleaner and more accessible energy to the impoverished communities.
The article mentions that the only current source of energy and heat is burning wood and coal which can cause tuberculosis and asthma. The transition utilizes solar powered hot water heaters and clean-burning cooking stoves which are types of active solar energy. This is a unique example of how solar energy can improve the health of less fortunate societies through Active Solar Energy. The other main method of solar energy is Passive Solar Heating. The major difference between the two types of solar energy is that passive solar heating doesn’t require the use of mechanical and electrical devices like active solar energy does.
Passive Solar Heating is used to collect, store, and distribute solar energy in the form of heat in the winter while also to reject solar heat in the summer. This technique takes advantage of the building design, but the designing must be done during the construction of the house or building. Examples of the building designs are things like positioning windows on the south-facing walls to let sunlight and heat in, covering roofs with dark material to maximize heat absorption, and having overhangs to block sunlight in the winter.
Here is a visual to passive solar heating:
This is a video that better explains how window positioning helps passive solar heating.
*While you don’t have to spend extra money on equipment, construction costs can run high but usually pay themselves off within a few years.
Active Solar Energy is used to convert solar energy into a more useful form of energy, such as heat or electrical energy. Examples of active solar energy are things like a small scale water heating system, photovoltaic solar cells, and large concentrating solar thermal systems. Water Heating Systems can be used for household water, public swimming pools, or businesses and is generally driven by a pump that is powered by the sun. A Photovoltaic Solar Cell is an electrical device that converts the energy of light directly into electricity. Many of the solar cells are paired together to make the solar panels that are seen on houses and buildings. Concentrating Solar Thermal Systems use mirrors or lenses to concentrate a large area of sunlight, aka solar thermal energy, onto a small area which then converts the light to heat. This drives the turbine that is responsible for generating the power.
*Active solar energy can generate hot water or electricity without polluting the air or water as it doesn’t produce CO2, but the installation of these technologies can be expensive.