How to measure accumulated solar panel energy?

Alternative Power For Dummies Understand how to reduce your bills: query Marek Z : How to measure the accumulated power solar panel I want to make my own mini-solar program project and I have to measure every day power accumulated. How you do it properly, due to the fact, as I do. So do not do issues, but the power to give the incorrect outcome is the energy of the battery and there are specific devices for? Of course, with the exception of standard counter: P Greatest Answer Thanks: need

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