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Question:

Can a solar panel work with an inverter?

The inverter I am using gets the required 2 DC volts from the solar panel, but fo some reason it just won't output the 0 AC voltage. When the inverter is hooked to a car battery, it works just fine off the same 2 DC rating. Help me out please...

Answer:

Solar panels output a very small amount of current. Even though you're getting 2V from the panels, you aren't getting enough amperage to power even the inverter itself, let alone anything plugged into the inverter. Car batteries are able to be used with inverters because they can crank out enough amps to power the inverter and whatever is plugged into it. Inverters only step up voltages and change DC to AC. They do not increase power (wattage) potential. If you want to plug in a 20W appliance into the inverter, the 2V source must be able to deliver 20W of power regardless of voltage. In pretty much everything solar powered, the panels are used in conjunction with batteries. The solar panels slowly recharge the batteries. The batteries are where most of the power comes from. Nothing is driven directly from the solar panels themselves unless the power requirement is low enough, such as a calculator. Solar panels will have an output rating in watts (W). If the wattage of your inverter plus whatever you plug into it is lower than the panel's output rating, then it can power it directly, provided you have 00% light input into the panel.
There could be a couple of reasons why it isn't working. First, 2V panels actually put out a considerably higher voltage because it is presumed that they will be used to charge a 2Vdc battery. That requires applying a voltage greater than 2Vdc, and usually there is a solar controller that regulates the solar power to the battery. It also has a voltage drop. Look at the first reference reference, and you will see these values for a particular panel: Voc: 2.6V (open circuit voltage) Vmp: 7.2V (voltage at maximum power point) Voc is the voltage the panel produces under standard sunlight and temperature conditions (25°C), with no load applied. As load is applied, the voltage drops (see reference 2). Power is the product of current times voltage, so at one set of conditions (namely at Vmp) maximum power is available from the panel. Your inverter might not be working for either of two reasons: ) it has input protection circuitry that locks out operation when it senses an overvoltage, as in the 2.6V open circuit voltage, or 2) the panel does not produce enough current and the voltage from the panel collapses under excessive load. For example, if you load your inverter to 20W, then nominally the 2VDC input to the inverter must supply 20W/2V/eff = 0A/eff Assuming the inverter has an efficiency of 80%, the input current required is: 0A/.8 = 2.5A A solar panel operating at maximum power would need a rating of about: 2.5A x 7.2V = 25W Is your panel that big? The other option, as mentioned by others, is to charge a battery that runs the inverter. Other nuances: Voc increases as temperature decreases. Sunlight intensity varies (obviously), so the panel may produce less than rated power. The power specifications often are printed on the back side of the panel.

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