I also had the thought that maybe go even simpler and use a fish tank heater connected to the panel. I may try that a bit while I order the pump. All my heaters are 110 ac. I'm thinking the regulation circuitry wont function but it may just heat anyway.
HOWEVER, if you fancy some entertaining ideas (especially if your solar panel has a waterproof junction box), you could try using the solar panel itself as a water heater (they sure get hot in full sunshine!), and the power from the panel to run a $15 pump. Solar panels actually are more efficient at low temperatures, so you'd (try to) kill two birds with one stone. Just a wild harebrained thought, at your own risk .
Is there anyway to use one of my inductive ac pumps I already have? Most are around 100 watts just that they are also 110ac.
- Inductive AC motors are terribly inefficient (50% efficiency or less, compared to ~75-90% for DC motors)
- Most cheapo Chinese inverters struggle with inductive loads. (Believe me, I have one: it may have only been $280 for a 3KW pure sine inverter--but it's a royal pain with any inductive loads! It is a true pure sine inverter--verified with an oscilloscope--but it's pathetic at starting anything inductive!) There is a rather hilarious YouTube video of someone (wajaeboseben) testing eleven (11) different cheap 12v inverters, rated from 350-1500W, to see if they could start a 1/2 HP synchronous (inductive) AC water pump. Most of them failed to start it--and two of them just produced a cloud of smoke.
- You might have a 100W solar panel, BUT an inverter will lose at least 10% of that power. AND if you have a PWM-style charge controller, there goes another chunk of power. In short, you'd need a bigger solar panel. Plus a timer to shut it off at night, or else the battery will end up getting fully cycled every day, and won't last very long
I'd just recommend getting a small BLDC pump or two, and wiring them directly to the panel. It'll be a lot cheaper, simpler, and efficient. (And in case you're wondering, no, it won't work to directly wire an AC induction motor to the solar panel. You can try it, but nothing will happen.)
NochiLife I am wondering how I can only use 20 or 30 watts out of a 100 w panel without a problem? Dont I need something to either use or store that energy? Like how I have to connect my battery first to the charge controller so the panel doesn't blow it out.
thanks for the great help
thanks for the great help
Maybe a bit of an analogy could help: a battery that isn't connected to anything is still providing power--it just isn't being used. If you put a solar panel in the sun without connecting anything to it, it's producing power--just the resulting power isn't being used. Like a car--it may have a 220HP engine, but it probably only takes 30HP to cruise down the freeway. For that matter, the panel will only produce 100W in full sun--in the mornings and evenings (or cloudy days), it'll produce far less.
The only possible issue would be if the Voc (open-circuit voltage, i.e. the voltage the panel will produce in full sun with no load) exceeds your BLDC pump's maximum voltage; if the specs you posted match the panel, you'll be just fine (22.4Voc at the panel vs. 24v max on the pump).
It's a lot of fun to see solar working for free.
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