Hey Guitar Man, you've opened a can of worms on this one, I'll explain. Bloodletter and Crazines are both quite right, for different reasons. The formula for Power is Energy times Time, you can find that in lots of engineering text books. So technically the terms are not interchangeable, but they do refer to the same thing in your case. The other side of it is that these are terms technicians use both in theory and in the field. We have a house that is powered by a solar array in the Upper Midwest. When I started researching all this almost 12 years ago, I had the same problem with terms. In the renewable energy field, "Solar Energy," is a term that describes exactly that, how much energy is streaming in from the sun. You can feel it as heat when it strikes your skin. You can also convert it to heat to heat water, air, or some other medium, and you can convert it to electricity using a photovoltaic, or solar panel. Once this conversion is done however, it is no longer considered solar energy. It might be heat energy if you are heating water, or electrical energy if you are running a light bulb, or even chemical energy if you are charging a battery. But to make things easier to understand, most technicians refer to any of these energys that are originally made from solar energy as, "Solar Power." This way it is easier to keep separate from other power sources, like natural gas, utility electricity, or even firewood in discussions. It is power derived from solar energy. Our home gets most of its electricity from our solar array, but can be switched over to the grid if there is a shortage, or mechanical problem. When we switch back and forth, we refer to the power as being, "Solar Power," or, "Utility Power." Again, these are not terms you will find in an engineering text book, but most everyone you say it too understands the difference, that's why we use them, for clarity.
I'll list some non profit groups below that you can look up online if you want to try to learn more, but it might not be easy to get an exact source for your school work at any of them. Maybe one of them will have a search engine at their website that can direct you to an explanation you can quote in your work.
I like your handle by the way, Gibsons are great. Do you know if they are still manufacturing guitars in Kalamazoo? Good luck with your school project, and take care.
Midwest Renewable Energy Association
Great Lakes Renewable Energy Association
Solar Energy International
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