We're looking to develop a rocket stove system to heat water that will then be circulated through pex tubing inside a custom fabricated bench where we will start our seedlings for a large organic vegetable farm. We may also desire to pipe the water through a heat exchanger with blower fan. Anybody have a proven system for heating water reliably with a rocket stove?
Greenhouse is roughly 20'x36' gothic style. Currently with single wall greenhouse film but we're preparing to replace that with some double layer of film. Located in Bangor, MI USDA Zone 6b about 15 miles west of Lake Michigan. Farm is 30 acres, completely off grid with solar, wind, and propane energy sources.
Also, I'm currently traveling from Northern California back to Michigan and would happily trade manual labor for the opportunity to view your system anywhere between here and home. Let us know if you're interested.
im surprised you have not been jumped on by a bunch of people yet to tell you that you may heat water but just dont do it with a closed system. there was a guy on my thread that said he was heating his water in Alaska for over 40 years in his closed loop system with no problems... i will never tell anyone to do or not do anything, i just suggest if you do anything its always best to do things informed and responsible. i am sure heating a closed system is possible if you know what your absolute max temps are for a 24 hour hard push of your system and calculate enough safety overhead in and configure your system to loop and circulate in a way that the water cools faster than it can reach a dangerous expansion level along with having multiple safety features built in. such a set up regardless of open or closed would need the heated pipe rising from the heat source into your water storage and then circulating back out the bottom to the heat source again and then tap into the system for your hot water. in order for it to circulate without electric pumps the water tank must be higher than the heat source. if its an open water system, you would coil copper pipes inside a heated open tank and draw hot water from the coiled pipes. i have a diagram on my thread.
Hi Philip; Welcome to the world of rocket scientists! Many things are possible, heating water can be done although it is challenging to do it safely. I have been heating our greenhouse with a RMH for three years ... love it !!! went from over 12 cord of wood to less than 5 !!! I simply removed all the dirt from one of our raised beds and used that space to create my mass 2.5 W x 3.5 tall X 14' long encased with clay brick and filled with stone and cob. This bench has surface temps from 60-100 we simply set trays of starts on top and they stay toasty warm even when its well below freezing outside and air temp in the green house is 40-45 F . You mention that you plan on replacing your single wall plastic with double wall ... consider solexx instead, its not cheap but it has a 20 year warranty for UV degradation, and has an R value !!! most good greenhouse grade plastic lasts 3 years then need replacing! My solex has wintered 3 years thru wind ,snow ,hail and is as good now as when it went up! Do not buy the ridged sheets look for the linear role it is 4'1.5" wide and they will ship just over 100' free! Having your rmh core inside your greenhouse will add huge amounts of heat to your building . Using a traditional "J" tube style like me or the newer batch box, either will provide all the heat you need . When it is below zero here we start the j tube in the morning and once its going well you will only need to check it every 40 minutes, we keep it going all day that way then let it go out between 9-10 at night . Room temp at the time will be 60-65 F next morning at 6-7 am , room air temp will be 40 F +and the temp on top of the mass will be 70-80 F near the core and 60-65 at the far end ! That is with outside temps of 0,-10 F!!! Good luck with your build!
We are looking to primarily heat water because we would like the system set up for multiple fuel sources. We would ideally like to heat the water using wood as the energy source because our location provides ample timber resources, sufficient for many, many years. We also are installing a large photovoltaic array to power an irrigation pump and the infrastructure is already in place for propane as an energy source for heating and electricity generation. Thus, we are looking for a system that uses a relatively universal method for transferring energy (this would be water) from our source of energy be it wood, propane, or electricity.
Initially the water will be heated with propane as we build the RMH. It is possible to build a mass within the greenhouse and I'm advocating for this but my boss may decide that he doesn't want to go that route.
I am also envisioning a stove with a batch box located outside the greenhouse and the heat riser located inside the greenhouse. This is basically one of the few mandatory features of the design.