What is a Solar Inverter Generator?
A solar inverter generator combines a large-capacity rechargeable power station with portable solar panels. They offer a cleaner, quieter alternative to gas generators for camping, tailgating and off-grid home backup power.
When shopping for a solar generator, pay attention to its usable battery capacity and surge output. Also, look for power stations with AC outlets and USB ports.
Inverter
The inverter transforms the DC power stored in the batteries into alternating current (AC) energy that’s compatible with most appliances. It also regulates electricity voltage and provides backup functions to support off-grid solar systems.
Inverters aren’t part of the solar panel itself, but they work closely with it. Sunlight strikes the solar cells on a panel, knocking electrons loose from a semiconductor wafer that’s usually made of silicon. The separated electrons form an electric current that is DC energy, but this type of power isn’t compatible with most electrical devices.
When it’s time to charge a device, the inverter converts DC energy into AC electricity. This electricity is then stored in the battery, which can hold enough energy to power appliances for hours.
Depending on the type of solar system, an inverter might perform additional tasks. For example, microinverters that attach to each solar panel independently optimize the panel’s output based on sunlight direction and shading. They also provide panel-level monitoring and troubleshooting to make it easier to expand a solar system in the future. A string inverter without power optimizers performs a similar function but at a more centralized level and is less expensive than a microinverter system. Nevertheless, it’s recommended to install a power optimizer when shading or complex roof lines are an issue. This will reduce the need for maintenance and repairs later on.
Batteries
A solar generator is a large rechargeable battery pack — similar to those used by smartphones and tablets for charging on the go — with integrated power inverters and line conditioners that can keep your appliances running during a power outage. Unlike a traditional gas generator, which requires you to push a button or crank it with a manual starter, a solar generator starts instantly and runs silently with little maintenance required.
The solar panels absorb sunlight, exciting electrons in photovoltaic cells to generate direct current (DC) electricity that is passed through the charge controller. The charge controller regulates the voltage solar inverter generator of electricity before storage, which helps prevent overcharging and extends the lifespan of the batteries. The batteries then store the solar energy until it’s needed.
Lithium batteries are ideal for portable solar generators because they offer more watt-hour capacity than lead acid batteries, while also being lighter and more compact. However, they tend to be more expensive upfront than other battery types.
Many solar generators are expandable, allowing you to add more batteries for additional capacity and long-term runtime. For example, Goal Zero’s Delta Pro portable solar generator comes with one 3,600-Wh lithium-ion NMC battery and can support up to four additional batteries connected with thick proprietary charging cables. This gives the Delta Pro a 10,800-Wh capacity, rivalling the runtime of some gas generators.
Panels
Solar panels generate electricity by absorbing sunlight and turning it outdoor solar lights for house into direct current (DC) power. Since most household appliances run on alternating current (AC), an inverter is used to convert DC electricity into usable AC power. Alternatively, solar systems can use batteries to store energy for when it is not available.
The basic principle is that when photons of sunlight strike the semiconductor material in the PV cell, its energy knocks electrons loose, which creates an electric charge. This charge is transferred to the metal frame of the solar panel where it creates a voltage that can be turned into AC electricity using an inverter.
A single solar panel produces about 2 watts of electricity in bright sun, but a typical system contains many panels. These are connected in series or parallel to increase the voltage and current capability of the solar array.
If a PV system has more energy production than the customer needs, it can be exported to the grid for credit through net metering. This is a common practice in countries where incentives encourage solar energy production.
Historically solar systems used central inverters, but the introduction of micro-inverters has changed the industry. These inverters optimize for each solar panel, enabling every one of them to perform at its maximum potential. This makes PV solar systems more efficient and robust, especially in locations with shaded roofs or orientation problems.
Chargers
The inverter is the brain of a solar generator, performing several functions beyond simply converting DC into AC power. It also regulates the flow of electricity, protects the battery from overcharging and promotes longevity. Inverters are much more expensive than generators, but they provide a smoother flow of energy, quiet operation and compact design. Inverters can even support higher loads, so they are the better choice for running appliances and equipment that require heavy duty power, such as motors or tools.
Many of our picks use maximum power point tracking (MPPT) charge controllers. These manage the conversion from panel output and make it easier to combine different panels from multiple manufacturers. However, it’s still important to ensure that the total input wattage from your solar array and the combined output wattage of your generator will not exceed the inverter’s capacity.
If you want the ability to recharge a device while using it, look for a model that allows simultaneous AC and solar charging. For example, the Jackery Delta 2 is one of the most popular small solar generators and offers this feature. It can handle up to 400W of solar input and can discharge a short burst of up to 1,800W for a brief period.
Another option is the Anker 757, which has a similar capacity and a wider variety of AC and USB ports than other models we tested. It uses LiFePO4 batteries and charges with an XT-30 or XT-60 adapter cable, which is compatible with most solar panels. It is also the smallest, lightest and easiest to carry of all our picks.
