Solar energy is an important renewable source that can be used to power our homes, cars and businesses. It is a clean and renewable energy that reduces our dependency on fossil fuels like coal and oil.
There are a number of different types of solar energy and each one has its own uses. They include thermal energy, photovoltaic power and passive solar power.
Photovoltaics
Photovoltaics is the process of converting light energy directly into electricity. This happens when photons of light (either natural or artificial) penetrate certain semiconductor materials, causing them to excite electrons to a higher energy state.
The resulting current flows through a device, such as a solar panel. Solar cells are made of different materials including silicon, copper, and cadmium.
PV systems are able to be connected to the power grid or used to generate electricity for homes and business. The cost of these systems is currently falling, making them a more affordable option.
Unlike CSP, which concentrates sunlight to heat a fluid into steam for power generation, PV uses photovoltaic cells to convert light directly into electricity. These cells can then be grouped to create modules, arrays or panels.
Solar power: concentrating solar energy
Concentrated solar power (CSP) is a technology that harnesses the sun`s thermal energy to produce electricity. CSP uses mirrors that reflect sunlight on a receiver where heat is stored.
A similar concept to solar photovoltaics, CSP systems can be used in utility-scale power plants and other large-scale projects. They can also be integrated with other renewable energy sources, such as wind and hydroelectric power.
The cost of concentrating solar power has been declining steadily since its inception, with an average levelized cost of energy (LCOE) of 18.2 cents per kilowatt hour as of 2019. This is the lowest cost of any renewable electricity source and is expected to continue falling.
There are several types of concentrated solar systems. These include parabolic dishes and solar power towers. They also include parabolic troughs and linear Fresnel system. All of them use rows of collectors that focus the sunlight onto a receiver. The receiver holds a fluid that can be used to store heat, or it can be used immediately to generate electricity.
Solar heating & cooling
Solar heating & cooling is the ability to use the sun`s energy to heat air or water in a building. This can be an effective way to reduce your monthly energy bill and contribute to the fight against climate change.
There are several solar heating options available, including solar hot water systems and solar air heaters. It`s crucial to know how your system operates and how you can maximize its performance.
Solar heating systems consist of three main elements: solar collectors (usually water), a heat-exchanger, and thermal storage. A working fluid (usually water) passes through the solar collectors, transferring thermal energy to another fluid used to heat or cool the air or water in a building.
Passive solar energy
Passive solar energy uses the sun`s rays to heat and cool buildings without using electrical pumps or fans. This is a cost-effective and efficient way to harness the sun`s energy.
A passive solar building does not use photovoltaics to convert the sun`s energy into electricity, but instead makes use of a combination of proper orientation, well designed shading and roof overhangs, window placement and orientation, non-mechanical heat storage, and convective air currents to warm and cool a home naturally.
In order to cool a passive solar house, the windows and windowsills on the shady north side of the building need to open and cool air can be pulled in from outside by causing a draft through high vents or opening shaded windows. The same principle applies to our Trombe wall or sun space design, which also utilizes convective air currents to warm the house and induce a draft that pulls the hot, heated air from the top of the room out into the house.