Hello, new to the forums. I am in school, as an Ecology major, but recently endured a long-awaited realization: I LOVE to build things! In my free time I find myself (attempting) figuring out how to build TEGs for our school's compost pile and creating all sorts of fancy aquaponics systems. I am taking physics and math courses for the remainder of my stay as an undergrad, and even staying longer due to this, in the hopes to get accepted into an ERE program after my bachelor's program is finished. We'll see. ;) This question isn't necessarily a homework question, but I figured belongs here as to not produce unneeded noise in other sections. I am too excited for this to wait for school to start up again to attend a physics club meeting so I figured I'd ask here: Note: While experimenting with these devices, I accidently spilled water on my laptop and.. it's dead. Fantastic. My responses may be a bit delayed as I need to ride my bike to the uni library. 1. The problem statement, all variables and given/known data Materials: Two TEC modules(DC) - 12V ~15Vmax Pb-Acid battery(DC)- 6V 4.5A. The TEG module output is relative to the heat differentiation, as you probably know. My problem is that with my limited knowledge, I cannot figure out how to set up this system, or how to change it, in order to charge the battery with these 12V TEC devices. Upon testing the output of both of the TEGs(together), I found I can build up to around 1.5V output. (~32degreesF / ~130degreesF | Large compost piles can become 160-180 degreesF) - Sorry about this being in Fahrenheit. In short, can I charge a 6V battery with a 1.5V source? I know that a simple circuit will not, because the voltage potential is higher in the battery. In fact, if I tried, all I would end up doing would be creating the Peltier effect instead of the Seebeck effect. But If I connect a 6V battery to 1.5V source, the TEG's would use the power (and heat up my compost, which is a plus), and the battery would lose it's potential, correct? Solutions? Once the battery drops to 1V, let's say, wouldn't the potential difference switch and the TEGs would charge it back to 1.5V or so, creating an equilibrium? Leading to another question: If I connected a battery to a battery, while the first battery charges the second battery to 1.5V, it loses voltage, so the TEGs connected to the first battery can continue to charge it, while it loses power to the second(or third, fourth, etc battery, etc.), eventually having a decent amount of charge in the combined batteries to use to light the bulbs? The same as using low voltage batteries, maybe? My second thought was interesting. What if I were to place a resistor(or light bulbs) between the battery and TEGs(TEGs--->battery --> Resistors -->TEGs) to create voltage drops so much so that the output of the TEGs may override the input? This is where my inexperience will surely shine. Since TEGs creating varying amounts of V, would the addition of a capacitor be of any help? Maybe switching to AC, going through a capacitor(from my understanding, AC will by itself discharge?), switching back to DC... but that sounds like a lot of lost energy, something this system can't really withstand. Could it fill the "peaks and vallies" creating by the TEG output? Can a capacitor store more energy than the output is releasing? I'm in over my head for sure, but am enjoying this so much so that I can't wait to continue studying. I apologize for my lack of terminology and such... Thanks so much for reading! I hope I can, with help, figure this out. It must be possible!!! I'll check back soon, Connor John Schmitz.