Which Shurflo? Most will use very little power, the model number on the pump will give us the info you need. I only use a 115V Shurflo, it uses under 2A. If you convert to DC, you also need the efficiency loss of the converter. Add the power used by whatever is doing the switching if any then your use will be the greater of the pump/converter/controller or the light bulb, not all since only one will run at a time.
Dave Klish, I recently ordered a 2x6 wood fired evaporator from A&A Sheet Metal which I will be converting to oil fired
Now have solar, 2x6 finish pan, 5 bank 7x7 filter press, large water jacketed bottler, and tankless water heater.
Recently bought another Gingerich RO, this one was a 125, but a second membrane was added thus is a 250, like I had.
After running a 2x3, a 2x6, 3x8 tapping from 79 taps up to 1320 all woodfired, now I'm going to a 2x6 oil fired and a 200-425 taps.