What is solar power?
Solar power is a renewable energy source that uses either sunlight or heat to create usable energy. It’s one of the most promising and abundant energy sources available. A 600 by 600km (400 by 400 miles) area covered in solar modules, can produce our entire planet’s annual energy needs. This could be one small corner of the Sahara Desert.
What types of solar technologies are there?
Within solar energy there are several types of technologies, each with their own advantages.
Solar
photovoltaics
PV is the most common solar technology, converting sunlight directly into electricity using solar cells within a solar module – also referred to as a solar panel.
Concentrated
solar power
CSP uses mirror or lens technology that concentrates sunlight on a receiver to generate steam, which drives a turbine generator that produces electricity.
Solar
thermal
Solar thermal uses installed devices that absorb the sun’s heat to warm water or heat building spaces.
Passive
solar
Passive solar describes the ability to heat buildings from the sun through good insulation and strategic window design.
How are PV cells made?
What is a solar module?
A solar photovoltaic (PV) cell turns sunlight into electricity by converting light (photons) into electrons. Each cell contains a positive and negative layer that allows sunlight to displace electrons from them to produce DC (direct current) electricity. A solar module incorporates several cells connected together.
A typical solar module (or panel) is roughly 1m x 2m x 40mm. Module efficiency ranges from 15% to 23%, and power ratings can vary from 250 Wp to 700 Wp. Module manufacturers typically warrant performance for 25 to 30 years. It’s not unusual for modules to last 40 years or more.
What is a bifacial solar module?
Bifacial solar panels absorb light from the front and the back of the panel, thus increasing the amount of energy that can be generated from a single module. These panels are produced similarly to traditional solar panels but have a transparent back sheet.
How are solar PV modules used?
Several solar modules are connected together to form a string or array. For the DC electricity to be used, it is normally converted to AC (alternating current) through an inverter.
To generate optimal energy, solar modules need maximum exposure to the sun’s rays. This is achieved by using racking to either secure them in a fixed position (fixed-tilt) or rotate them to track the sun (tracking).