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摘要

I have a non-functional PV module that powers the pump of a 17-year-old still-functioning solar water heating system (manufactured by a company that is no longer in business). I'd like to replace the module, but how do I determine its wattage so I can buy a suitable replacement? The ink on the module's label has faded, though the name looks like Solarex, which is also no longer in business. The module has a black plastic base and 13 5/8-inch square frame. The module is probably 10 watts, which, back in the day, is in the range of power you could get out of a square foot of PV. You can count the number of cells to determine the voltage, but it's likely a 36-cell module, which is for 12 V nominal applications. Any full-service retailer should be able to supply you with a new module.