A solar panel is a device that converts sunlight into useful energy. Most solar panels are photovoltaic (PV) panels, which generate electricity for homes, businesses, vehicles, remote equipment, and utility-scale power grids. Solar thermal collectors use sunlight as heat for hot water, space heating, and swimming pools.
Common Uses of Solar Panels
| Use | How solar panels help |
|---|---|
| Powering homes | Rooftop PV panels generate electricity for lights, appliances, heating, cooling, and other household equipment. |
| Supplying businesses | Commercial systems provide electricity for offices, stores, factories, warehouses, and farms. |
| Generating grid electricity | Large solar farms use arrays of panels to supply electricity to thousands of homes and businesses. |
| Charging batteries | Solar panels charge batteries for use at night, during cloudy periods, or during power outages. |
| Providing off-grid electricity | Solar systems provide power where utility lines are unavailable, including remote homes, cabins, and field sites. |
| Operating remote equipment | Small systems can power water pumps, telecommunications equipment, monitoring stations, and lighting. |
| Heating water or buildings | Solar thermal panels use sunlight to heat water, air, or other fluids. |
How Do Photovoltaic Solar Panels Generate Electricity?
Photovoltaic panels contain solar cells made from semiconductor materials. When sunlight reaches the cells, they produce direct-current electricity. An inverter normally changes this electricity into alternating current, which household appliances and the electrical grid use.
A complete solar power system may include:
- Solar panels
- Mounting equipment
- One or more inverters
- Electrical wiring and safety equipment
- A battery storage system, if backup power is required
- A connection to the utility grid, for grid-tied systems
What Are Solar Panels Used For in Homes?
Home solar panels are mainly used to reduce the amount of electricity a household buys from its utility company. The electricity can power:
- Refrigerators and freezers
- Lighting
- Air conditioning and heating equipment
- Computers and televisions
- Washing machines and other appliances
- Electric water heaters
- Electric vehicle chargers
A grid-connected home can use solar electricity during the day and send surplus electricity to the grid where local rules allow it. When solar production is insufficient, the home can draw electricity from the grid. A battery can store some daytime production for use after sunset.
What Are Solar Panels Used For in Businesses and Industry?
Businesses and industrial facilities use solar panels to generate electricity for lighting, cooling, computers, machinery, refrigeration, and ventilation. Manufacturing facilities and other industrial sites can install solar systems on rooftops, parking structures, or nearby land. Some businesses use the electricity directly and send excess generation to the grid.
Solar power can be useful for facilities that consume much of their electricity during daylight hours, when the panels are producing energy.
What Are Solar Panels Used For Off-Grid Power?
Off-grid solar panels provide electricity without a connection to the main utility network. A typical off-grid system combines solar panels with batteries, an inverter, and charge-control equipment.
Common examples include:
- Remote cabins and homes
- Agricultural water pumps
- Livestock watering systems
- Emergency communication equipment
- Traffic and security lighting
- Weather and environmental monitoring stations
- Portable power systems
Solar PV systems can range from a small panel for a single device to large arrays capable of supplying utility-scale electricity.
Are All Solar Panels Used to Make Electricity?
No. The term "solar panel" can refer to more than one technology.
Photovoltaic Panels
Photovoltaic panels convert sunlight directly into electricity. They are used for:
- Rooftop electricity
- Solar farms
- Battery charging
- Portable electronics
- Off-grid systems
Solar Thermal Panels
Solar thermal panels collect the sun's heat instead of producing electricity. They can heat:
- Domestic hot water
- Swimming pools
- Indoor air
- Fluids used in solar thermal power plants
The two technologies perform different jobs. A PV panel produces electricity, while a solar thermal collector produces heat.
What Can Solar Panels Not Do by Themselves?
Solar panels cannot produce electricity at night, and they produce less electricity when sunlight is weak. A solar system therefore needs grid electricity, battery storage, or another backup source when solar generation does not meet demand.
Solar panels also produce direct current, so most buildings need an inverter to use the electricity with standard appliances.
Bottom Line
Use photovoltaic panels when the goal is electricity. Use solar thermal collectors when the goal is heat. Batteries, a grid connection, or another backup source can provide energy when sunlight is unavailable.