I have a homemade greenhouse or a hot house for some years now but ive never had a way to heat it and I could only use it in the late spring and by then it’s easier to start stuff outdoors. This year the greenhouse needs updated so I drew up some plans to put in a rocket mass heater. But I had an idea of using water as the mass in the rocket mass heater (along with some clay/cement mix as mass too).
My dad works at a place that makes vitamins and they have big 55gal drums that they throw out and I was thinking that I could put water in the drums and run them along exhaust. That way the rocket mass heater heats up the water to a hot temp and over the night the water slowly cools down and keeps the greenhouse warm all night.
Ive herd of people using water as a passive solar heater so I guess this would be a hybrid between that and a rocket mass heater. Do you think It could work? And I don’t know the specifics of a rocket mass heater but I do have an idea of how it works, would a 6in gap between the top of the rocket mass heaters barrel and the riser (I think that’s what you call it) in the barrel work? As I want the heat to be all over and not just on the top of the barrel (like some people have to make tea).
Heres a pic of my plan to show you what im talking about:
and heres what my greenhouse looked like new a few years ago:
How are you channeling your exhaust through the H20 for thermal mass?
Richard Gurry wrote: However it has a lot of surface area exposed to outer walls. Maybe put mylar blankets around bottom 2-3 feet of green house where radiant heat from your thermal storage could be reflected back.
The green house will have square sides with a plywood wall on the front back and the left side. The walls will be insulated with straw, and I think I might put some Mylar blankets down now too. Also Here is a pic of what it will look like.
And just for comparison heres the old design:
Richard Gurry wrote:How are you channeling your exhaust through the H20 for thermal mass?
Heres a little mock up I made with some scrap pipe and barrels. The white PVC pipe would be the 6in metal ducting exhaust. There would be a clay concrete mixture filling up all the air space around the barrels and pipe.
We are considering barrels in our walipini design as the retaining walls and have discussed the same concept, except we are going to be building upwards (stacking barrels). We are thinking of sand clay mix in the bottom barrels, then water in the ones above. The bottom barrels will take the direct heat, the upper barrels will get passive heat.
But i would use cob for the barrels that are closest to the heater, also i would put them a bit more apart. This way the water will have less difference in temperature between barrels. Also do not fill the barrels full!
The plastic arrives: