Edge Collective
Off-grid heat
Designs for off-grid heating systems2021-11-22 10:52:14
Terminal type is now 'qt'
gnuplot> set datafile separator ","
gnuplot> plot "output.txt" using 1:2
gnuplot> plot "output.txt" using 0:2
gnuplot>
~/gitwork/offgrid-heater/v1
stepping down at 10 min intervals:
next up:
- display in F
- record timestamp
~/gitwork/offgrid-heater/v2
2021-11-22 18:37:23
In v3, tried two heaters in parallel. Got:
Now re-trying one without changing position of temp sensor, for direct comparison ...
Now re-trying with three in parallel ...
Testing linearity by plotting equilibrated temp vs pwm for that temp:
2021-11-23 08:03:59
Arduino PID https://www.teachmemicro.com/arduino-pid-control-tutorial/
Three paralllel heaters:
Note that as of now (2021-11-23 08:06:17) the battery voltage is approx 12V; early in the experiments it was at 13V.
Now, return to one heater, repeat experiment, see if lower voltage has had an impact ...
2021-11-23 11:01:49
Results from one heater experiment. Note that the initial temp was higher, so perhaps easier to reach max temp initially; second run seems to reach lower max temp.
2021-11-23 12:52:43
Next step: add a diode and test ... and add a fuse?
2021-11-23 13:13:26
Nice guide to using N-channel mosfet w/ motor control ... https://bildr.org/2012/03/rfp30n06le-arduino/
2021-11-29 16:59:02
"Motorcyclists make their own heated clothing ..."
https://www.bimmerforums.com/forum/showthread.php?1563924-Converting-non-heated-seat-to-heated
https://advrider.com/f/threads/35-00-heated-jacket-liner-diy.514532/
Hook-up wire https://www.mouser.com/c/wire-cable/hook-up-wire/?q=83000
https://www.youtube.com/results?search_query=diy+heated+jacket+wire
Interesting -- he threads his own nichrome wire into insulation:
https://www.instructables.com/Solar-Water-Heater-From-Scratch/
advice on copper coil dimensions:
https://youtu.be/4JFdDITCH-8?t=388
Official design for wood-stove hot tub w/ some specs: https://islandhottub.com/wood-fired-heater/understanding-thermosiphon
To produce thermosiphon circulation, the top circulating tube must rise upward to the tub at a rate of 2-inches per foot or greater for the horizontal distance. The steeper the slope, the faster water circulates. Note: Faster circulation does not produce a faster heating rate.
Subtleties in designing a thermosiphon system: https://www.greenbuildingadvisor.com/question/thermosiphon-vs-recirculating-pump
Article on hot water systems: http://www.garykleinassociates.com/PDFs/15%20-%20Efficient%20Hot-Water%20Piping-JLC.pdf
Thermosiphone on appropedia https://www.appropedia.org/Thermosiphon
Hot water heater https://earthshipbiotecture.com/do-it-yourself-solar-hot-water-heater/
Nice review of thermosiphon materials https://www.sciencedirect.com/topics/engineering/thermosiphon-system
Likely reason for use of silicone in heating elements: its unusually high melting / burning point: https://silicone.co.uk/news/temperatures-can-silicone-rubber-withstand/
2021-12-16 16:45:58
2022-01-16 11:56:19
Cement home stove https://www.youtube.com/watch?v=tJmzTLlQpLw
2022-03-28 13:12:41
Rocket stove design -- with wire mesh -- https://www.theartofdoingstuff.com/diy-rocket-stove-outdoor-cooking-needs/
build a rocket stove -- https://gardenerd.com/blog/build-a-rocket-stove/
rocket stove instructions https://www.ywambelt.org/wp-content/uploads/Rocket-Stove.pdf