I'm looking to set up a simple solar power system in my backyard using an old 100W solar panel. My main goal is to run 12V devices like peltier coolers and possibly grow lights, and I also want the capability to charge phones, tablets, and laptops—though that's a secondary concern. I don't really plan to store any power since everything will be running directly off 12V. If I do need phone charging, I could use separate portable battery banks that charge via 12V. My question is, can I just use a DC-DC 12V converter and some basic circuitry since I don't need energy storage at this point and the power must not be stable?
2 Answers
It's important to know how much energy you plan to use each day. That helps you determine the battery capacity and solar power you'll need. Even if you're not planning on storing energy right now, keep that in mind for future setups!
Just a heads up, solar panels can be tricky. Most of them don’t actually output a true 12V; they’re typically in the 18-25V range. You'll likely need a charge controller to manage the voltage appropriately. Also, keep in mind that solar panels have variable output based on weather conditions and other factors, so having some battery backup is usually a must, even for basic setups. Also, peltier coolers and grow lights require a lot of power, and solar panels only convert about 30% of sunlight to electricity. You can use a DC-DC converter, but you might end up with less power than expected. A better route would be to set up a system like this: solar panel -> charge controller -> battery -> DC-DC regulator -> 12V devices. And remember to use appropriately sized wiring to prevent voltage drop!
Thanks for the info! I actually have a solid understanding of how solar works; I just didn’t specify that my panel is around 18V. I get the efficiency issues with peltier systems. I’m considering running some directly to test efficiency, but I may still go with the battery solution in the future.