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FREE Inverter Guide
for your system is right here in this guide, including the different types of inverters, recommended brands, and more.
An inverter is a critical piece of equipment in any PV system. The inverter takes DC power, either from your solar panels or batteries, and turns it into AC power, ready and usable for your household appliances.
Grid-tie and off-grid solar systems use different types of inverters.
In a grid-tied system, solar panels connect directly to an inverter which ties into your main household electrical panel. It sends power into the home to run appliances and turns back the meter with excess energy.
Grid-Tie inverters come in several options: string inverters, microinverters, and optimizers. Each varies with features and costs. For helping choosing the right one, check out our article on the best grid-tie solar inverters.
Though string inverters derive from the oldest technology, modern string inverters have improved substantially and provide a cost effective option for many. In a string inverter system, solar panels are wired in a series string for high voltage (typically 300-600Vdc.) We’ve sold the SMA Sunny Boy string inverters for years and recommend these for installations where solar panels stay relatively free of shade.
Optimizers are DC-DC converters that connect to each solar panel, similar to a microinverter but a central inverter still handles the DC-AC inversion. Power optimizers attach to each panel for easier and safer installation, easy expansion, bigger string sizing, and module-level monitoring. SolarEdge is a leader in optimizer technology and one of the most popular residential inverters. We have this installed on our own office. Power optimizers combine the best features with a competitive price.
Microinverter systems have a small inverter attached to each panel. This type of inverter costs more, but it is also expandable, safe and easy to install, and is capable of monitoring every individual solar panel. Because each panel can operate independently, microinverters are a better option if there is shade on part of the solar array from trees, buildings or other obstacles. Microinverters tend to be the most expensive inverter system, but they provide key benefits like ease of installation, expansion, and module-level monitoring. We recommend Enphase Energy microinverters for anyone looking for these features.
Off-grid inverters connect to a battery bank and change DC battery power into household AC power. Off-grid inverters work with 12v, 24v or 48v battery banks.
The AC output is typically 120Vac for smaller inverters, and 120/240Vac for larger units. We also sell export 230Vac 50hz inverters for systems installed outside of North America.
Some off-grid inverters have an extra connection that enables them to function like a grid-tie inverter and sell power into the grid. This is useful if you start out off-the-grid but plan for power lines in the future, or if you live in an area where utility power is unreliable.
Off-grid inverters are a little complicated, due to the extra components involved in an off-grid system. For help picking the right off-grid inverter, check out our article about the best off-grid inverters. Or give our solar experts a call at 1-800-472-1142.
You’ll hear inverter manufacturers use phrases such as pure sinewave and modified sinewave. This is a measurement of the quality of the AC output power. Pure sinewave inverters put out power that is as good, or potentially better, than what is coming from the power grid. Almost all appliances will work with pure sinewave inverters.
Modified sinewave inverters have lower power quality which causes issues with certain appliances. Motors, pumps and compressors (like your fridge) will tend to run hotter and burn out quicker. Modified sinewave inverters can be problematic for sensitive electronic devices, often causing lines on your TV screen and a buzzing sound from the speakers. Some appliances won’t work at all on a modified sinewave inverter. For these reasons, we recommend sticking with a pure sinewave inverter unless you are sure your appliances can work on modified sinewave power.
If you’re looking at inverters, chances are you also need a complete solar system, including solar panels, racking, and more.
If you’re connected to the power lines, checkout our grid-tie packages. If you’re going off the grid, take a look at our off-grid solar kits.
Still not sure what kind of system you’re looking for? Get our FREE Getting Started Guide. It covers all the basics of solar power.