What It Is. Photovoltaic (PV) solar panels convert sunlight to electricity. The most common types of PV solar panels are madeof crystalline silicon solar cells. The electricity produced runs through an inverter that converts the current into electricity that can power anything from a toaster to a TV to an electric car.What to Expect. Photovoltaic solar power is an established technology, and with no moving parts, photovoltaic solar panelsoffer reliable, long-term energy production. The best residential solar panels offer efficiencies of up to 18% to 19%, producing the most possible electricity per square foot. Typically, residential solar panels are roof-mounted, although ground-mounted PV systems can be installed where more land is available. Photovoltaic solar panels generally require very little maintenance, and in areas that offer net metering, excess electricity can be sent to the local grid so that you earn money from your solar investment.
Solar thermal panels transfer the sun’s heat, as opposed to generating electricity. Their most popular application is to heat water. Subsequently, solar thermal is a great technology to offset energy usage for your water heater or for heating an outdoor pool. Solar thermal power can also be used to heat or cool a home, depending on the specific solar thermal technol- ogy. Since most residential heating systems use gas, this solar technology primarily offsets gas usage.What to Expect. One popular type of solar thermal heating system uses pipes filled with water in conjunction with solar ther- mal panels. The sun’s heat is conducted through the solar thermal panels to heat the water in the pipes. There are generally two types of these solar thermal systems: active and passive systems. Active systems use pumps and controls to regulate the hot water. Passive systems do not, and they are typically only feasible in mild climates where risks from extreme temperatures (like freezing) aren’t present. There are also slar thermal heating systems that heat homes by radiating the heat from the pipes to warm the air.When to Buy. Solar thermal heating systems can be a great complement to a photovoltaic system. Especially when your home has high gas usage, solar thermal systems can be installed to offset that usage while a PV system can be installed to offset electric usage. Combined, they may allow you to become nearly energy independent. The key component is reviewing where your home’s biggest energy demands are to figure out which type of solar system or what combination will make the most sense for you.