In theory, solar electric panels can draw power from any type of light source. Even when a solar panel is exposed to artificial light, its voltage will still activate. However, solar panels used to power anything larger than a cell phone charger or calculator do need large amounts of sunlight to work effectively. Panels used to power electricity in a house, for example, will only work with significant amounts of direct sunlight. During the day, the solar mechanism draws enough energy from direct sunlight into a heat storage component, allowing this solar energy reserve to continue powering the house's electricity even after the sun sets.