My first year I made enough to be able to sell some, I had a 2x3 flat pan on my patio. I put up a vendors type tent over it and the smoke stack went up at about 45 degree angle and was braced up by EMT attached to my deck railing. It took a long time, boiling at between 5.5 -6 gal/hr. That summer I started my sugarhouse and bought a used 2x6 evaporator. Way better with a roof and walls, but it got done without too.
With either electric or propane you will want to do as much as you can to improve evaporation efficiency, both methods are going to be pricy to say the least.
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.