For an engineering assessment (first year with no electrical background), we are using a solar panel to power an element for a distillation system. we have calculated our heat energy output requirement that we need from our heating element as being 800 J/s. For simplicity we are assuming 100% heat transfer into the system.
My understanding is that if we have a 12V 140W panel, we have 11.67A, similarly 5.83A for a 24V 140W. Is it wrong to combine joule's law and Ohms law to end up with P=I2R, and then apply that to calculate the heat energy released from the element to then suit it to our initial heat energy requirement? P's units being in Joules and the resistance can vary based on the current from the solar panels.
In looking online for potential elements, many have high Watt ratings, what would happen if you attempted to use a 400W DC element in that 140W solar panel system. Currently i understand it as the voltages need to match, i.e a 12V panel needs to supply a 12V element. Is that train of thought wrong?
Any help would be appreciated,
Thanks in Advance!