Armchair sandbattery enthusiast here... Too bad you had to cut it smaller but I'm impressed with how quick you implement design changes. I think I understand that you made it smaller in order to get the sand to a higher temperature, what are your thoughts on wrapping the barrel with thermal insulation? My neighbor moved and they left me an old rusty oil drum, I'm inspired by your work and hopefully will be able to cobble together something similar.
I will show another drawing of my plans. Next I will frame it in with a metal box that I will draw hot air from with fans. Then it will get insulation and a final outer metal skin.
Hi Mike! Love your project and your videos keep up the good fight! I'm wondering if something's wrong. When I do the engineering calcs of wattage required seems like you should be getting more temperature gain even with the original 55 gallons of sand. Are you sure you're the heating elements are working optimally and have you measured your actual watt hour input or are you going by stated pannel/array labels? Also I realize my calcs take no account for the wind sucking heat off the drum which is probably substantial. Further i did not account for inefficeincy of the elements but still I would expect 2-3 times what you showed.
I don't have a lot of cross checking I can do with my limited equipment and knowledge. But just thinking about it from a basic standpoint. I am trying to heat up 700 pounds of sand with a minimal 1,020 watts. That is barely enough power to run a hot plate. Not only that but it is only getting power less than 12 hours a day so I don't think it is enough power. I know it is not heating like my earlier prototypes that had less mass. Thank you for your interest. I have more breakthroughs coming up soon.
Yeah ..seems to me a hybrid solar/ wood design would get you there..sun during day then fire at nite to maintain heat while using it. You gonna need a ton of solar to be able to harvest heat for more than an hour or so maybe?
That is the big question. Will it heat a small cabin over night? I believe it can be done. How many watts it will take is another question. I have thought of a hybrid design like you mentioned with a wood stove built into the system. Thank you for the comment and for watching.
@off-gridsurvivalmike8120 ps you mentioned a small cabin.im wanting one for my truck camper..as you know in science energy in =energy out..with heat it's a function of time and volume..a small mass might still work if it's highly insulated and the temp demand is low.. ie short fan bursts thru the exchanger to control the discharge rate.
It wasn't going to be enough wattage to heat the 55-gallons so I am raising it to 5-watts per pound of sand. Funny you mention the wind turbine. I may try connecting it eventually.
Keep it going Mike, that's the way!
I was more excited for then then the election results. Glad yr still on the Celsius. :) Hurray for sanity!
Ty!
Great job! Keep up the good work
Armchair sandbattery enthusiast here...
Too bad you had to cut it smaller but I'm impressed with how quick you implement design changes. I think I understand that you made it smaller in order to get the sand to a higher temperature, what are your thoughts on wrapping the barrel with thermal insulation?
My neighbor moved and they left me an old rusty oil drum, I'm inspired by your work and hopefully will be able to cobble together something similar.
I will show another drawing of my plans. Next I will frame it in with a metal box that I will draw hot air from with fans. Then it will get insulation and a final outer metal skin.
That sure is a good rule of thumb to keep in mind, 5 watts per pound. What do you think 4 watts per pound or 6 watts per pound would be ideal for?
Hi Mike! Love your project and your videos keep up the good fight! I'm wondering if something's wrong. When I do the engineering calcs of wattage required seems like you should be getting more temperature gain even with the original 55 gallons of sand. Are you sure you're the heating elements are working optimally and have you measured your actual watt hour input or are you going by stated pannel/array labels? Also I realize my calcs take no account for the wind sucking heat off the drum which is probably substantial. Further i did not account for inefficeincy of the elements but still I would expect 2-3 times what you showed.
Interesting.
I don't have a lot of cross checking I can do with my limited equipment and knowledge. But just thinking about it from a basic standpoint. I am trying to heat up 700 pounds of sand with a minimal 1,020 watts. That is barely enough power to run a hot plate. Not only that but it is only getting power less than 12 hours a day so I don't think it is enough power. I know it is not heating like my earlier prototypes that had less mass. Thank you for your interest. I have more breakthroughs coming up soon.
Could you share how you calculate the wattage needed?
Yeah ..seems to me a hybrid solar/ wood design would get you there..sun during day then fire at nite to maintain heat while using it. You gonna need a ton of solar to be able to harvest heat for more than an hour or so maybe?
That is the big question. Will it heat a small cabin over night? I believe it can be done. How many watts it will take is another question. I have thought of a hybrid design like you mentioned with a wood stove built into the system. Thank you for the comment and for watching.
@off-gridsurvivalmike8120 I'm getting ready to build one for myself so will be following your experiences and share anything worthwhile I find out.
@off-gridsurvivalmike8120 ps you mentioned a small cabin.im wanting one for my truck camper..as you know in science energy in =energy out..with heat it's a function of time and volume..a small mass might still work if it's highly insulated and the temp demand is low.. ie short fan bursts thru the exchanger to control the discharge rate.
Too bad you don't have more solar panels.
What is the reason you are not adding in extra power from a wind generator? t least, it would keep the temperature up overnight.
It wasn't going to be enough wattage to heat the 55-gallons so I am raising it to 5-watts per pound of sand. Funny you mention the wind turbine. I may try connecting it eventually.