Solar panels are quickly becoming a way for everyday homeowners to convert sunlight into electricity. The term solar panel refers to two types of devices: photovoltaic (PV) modules - also called solar cells, and solar thermal collectors that are used in solar water heating. For more information on solar thermal collectors, visit our solar water heating page.
Solar energy is a renewable source of energy that is available almost everywhere in the world and can be used to provide heat, light and electricity. It is also free and is not subject to fee changes.
PV cells or solar cells are large semiconductor devices made of silicon used to capture the sun’s energy and convert it into usable energy. They can be used to power devices as small as a calculator or large enough to power an entire home. PV cells come in a variety of sizes, but the most common are 10 cm by 10 cm and generate half a volt of electricity. Cells are then bundled together to create Photovoltaic modules. These modules also come in a variety of sizes. The amount of energy output will depend on how many cells are in the module. For instance, a 12-volt module would require 30 to 40 cells.
PV panels are not the most efficient energy producers, with early models converting energy at only 12-15%. However, newer prototypes are reaching 30% efficiency. The lack of efficiency means that to get the desired energy output you wish, you will likely need to purchase a large number of panels, which can be an expensive proposition. However, given their 30 year average lifespan and the fact that you will not have to pay for the energy from a PV panels, it may be worth the up-front cost.
The last thing to consider is that PV cells and panels only convert light to direct current (DC). DC is the same current produced by batteries. Outside of incandescent light, most electric and electronic devices work on alternative current (AC). This means an inverter is required to convert DC to AC. Models vary in size and quality. The less expensive an inverter, the less likely it is to power larger AC appliances.