Finally, they return through the conductive aluminum sheet at the back. Although each silicon cell produces only half a volt of power, you can combine them into modules to increase your power. Twelve photovoltaic cells are sufficient to charge a smartphone, but it takes many modules in order to power a whole house. The only moving part in a solar cell is the electrons, and all of them return to their original place.
Solar cells are durable and can last for many decades. What’s the problem with solar power?
There are many political factors involved and businesses lobbying to keep the status quo. Let’s not get too involved in political and business issues. The most obvious is the uneven distribution of solar energy across the globe. Some areas are more Sun than others, and less sunlight is available at night or on cloudy days. Total dependence on electricity would require effective ways to obtain power from sunny areas to cloudy ones and efficient storage. It is also difficult to optimize the cell’s efficiency. If sunlight is reflected rather than absorbed, or if electrons that have been lost are redirected into a hole, the photon’s energy will be lost.
