Photovoltaik is a technology that converts sunlight directly into electricity using solar cells. These cells are made from semiconductor materials, typically silicon, which generate an electric current when exposed to sunlight. This process is known as the photovoltaic effect and is a key component of solar energy systems. Photovoltaik systems can be installed on rooftops, in solar farms, or integrated into building materials. They provide a renewable energy source that helps reduce reliance on fossil fuels and lower greenhouse gas emissions. As technology advances, the efficiency and affordability of photovoltaic systems continue to improve, making solar energy more accessible.