Solar panels can last for 25 years or more. However, their efficiency will gradually decline over time.

The amount of energy that solar panels can generate depends on a number of factors, including the size of the solar panels, the amount of sunlight they receive, and their efficiency. In South Africa, solar panels can typically generate between 200 and 300 watts of electricity per square meter.

There are two main types of solar panels: crystalline silicon solar panels and thin-film solar panels. Crystalline silicon solar panels are the most common type of solar panel. They are made from silicon crystals, which are arranged in a grid pattern. Thin-film solar panels are made from a variety of materials, including silicon, cadmium telluride, and copper indium gallium selenide. They are thinner and lighter than crystalline silicon solar panels, but they are also less efficient.