I recently joined a Facebook DIY solar group. Some of the advanced groups can be very helpful with advanced tips. This was not one of them.
In fact, this may have been the opposite of that, at least in many cases. It still keeps me up to date on popular equipment and trends, but, hoo boy, some of the questions!
A lot of times the first impression of a poster is, “this guy’s a dangerous idiot.” That’t harsh, though sometimes true. Largely, though, they are just ignorant. Ignorance can be no less dangerous, but it can be fixed. If you are a solar newbie and know that you need to learn stuff, there are many free guides on the Internet and there are many books available. I think there is even a “Solar for Dummies.”
You might even find something useful, here.
You need to learn to ask the right questions if you are going to ask, or you will get 832 responses that are all the same and it won’t be pretty. Typically, someone will post, ” I got a solar panel and a battery and an inverter, can I run my lights, my fridge and my a/c on this?” OMG.
The proper way to ask the question is to include necessary details. Unfortunately, the poster comes back, when pressed, with, “I have a 50 watt panel, a 12v 100ah car battery (second hand) and a 2000 watt Harbor Freight 12v inverter. The lights use 80 watts for 6 hours per night, the fridge uses 350 watts at 75% duty cycle and the a/c runs constantly at 800 watts.”
Well now, that’s some information we can use. It doesn’t come that quickly, though. You really are not going to stare at the fridge for 24 hours to get the duty cycle and you may not find where they hid the plate with the power info on it. A handy gadget you will need is a Kill-a-Watt. Plug it into the wall and then plug the fridge or a/c into it. After a day, it will display how much power you used. Now we know our load!
Now, the answer to the original question is invariably going to be NO! You could also get, “Yes, for about 15 seconds.” There is a fundamental fact of life with solar, you have to have it to use it. Also, at some point, you had to capture the power, before it could be used. The most fundamental point is that you must make more than you use. It is common to see someone do a good job of describing the pertinent details with the complaint that the system ran 2 days and went dark. He used more than he made.
Back to the original hypothetical post. There is a 50 watt panel. How much power you get out of that will vary with time of year, weather, orientation to the sun, shade, cleanliness, etc. Where I live, we allegedly get 5 hours of equivalent full sun. (Look for a solar phone app) So 5 hours X 50 watts gives us 250 watt-hours of production. Never mind some other important details, 250 watt hours won’t run the fridge 24/7. Not even for an hour. It won’t run the a/c. The lights use 80 X 6 or 480 watt-hours, so, “NO!” It ain’t gonna work.
Next time, we’ll follow this up and get to something that will work for the fellow.–Neal