With a properly built Rocket Stove, you can't have a real chimney fire either since you are having a controlled chimney fire, in the super heated burn chamber/tunnel and heat riser, which burns off what would be the cooler gasses and particulate (in a regular wood stove) that might produce creosote. A batch box RMH takes care of the longer burn time aspect.
There is the longer burn times and ease of use of coal for sure, but it primarily is because you just cannot have a chimney fire with coal since it has no creosote. I LIKE THAT!!
The fuel savings of having the RMH would show in labor reductions, and you wouldn't have to sell wood to buy propane... or a lot less. If you hooked up your RMH to produce hot water, heating water for your floor, then you are killing two birds with one stone... or actually the same bird (heating your house) with two stones. ...or even three, since there's the barrel radiating, the slow radiant of the bench, and the hot water in the floor.
The problem with wood is not if I have enough, it is that I cut too much of the stuff.
You don't have to build the pipe bench. You can build a vertical bell instead. There are plenty of options, I think, for an situation. I'm hardly in a position to consult on it, but there are others on this site who are quite knowledgeable.
I guess if I have any concerns it would be the amount of room a RMH requires, I am at a premium for space in this house.
Fair enough. I'm just playing a bit of devil's advocate, and forcing the RMH discussion, because it did seem that your reasons for not doing it were not as justified as you described them.
But if a billion dollar company determined my farm is ideal for wind, then I should certainly be tapping into it.
Marcos Buenijo wrote:Bill, I second (or third) the idea of "stirring" water contained in an insulated vessel for heating. See Joule's work in thermodynamics during the 1800's. Cavitation is not required, but may be unavoidable. Any resistance to the motion of the "paddles" contained in the vessel will transfer energy to the water to raise its temperature. I used to work at an experimental power plant that placed a large "water brake" on the output shaft as a load. The same principle applied there even though it was basically a large hydraulic pump that sent the water through a restriction. On that note, you could drive a vane pump (hydraulic) with the wind turbine sending the discharge of the pump through a pressure relief valve, and contain the whole apparatus within an insulated vessel. If the vessel were pressurized, then this could help minimize any cavitation in the pump.
However, note that wind turbines generally have to be elevated for good performance. Therefore, there would be extreme thermal losses involved in containing the heated water and especially in transferring the heated water to an end use. I expect the losses to be greater than those seen by a good alternator. So, it makes more sense to use the wind turbine to drive an alternator, then send the DC output directly to a water heating element. This is often done as a "dump load" in diversion battery controllers, but in this case one would just connected the alternator directly to the element and call it a day. If it's heat from wind that you want, then this is actually an elegant solution.
Luke Townsley wrote:It could have enough energy to make steam. It just depends on how much energy you put in. Whatever you put in is what you will get out.
You can't really just put a paddle in a barrel though. The water would swirl with the paddle and not make much friction against the smooth sides of the barrel. You would need to put stationary vanes on the side of the barrel to slow down the water to make more friction.
Perhaps you could adjust the vanes according to the paddle speed to help keep the wind turbine moving at optimal speeds.
The ingenious among us could probably come up with a paddle design that didn't require stationary vanes. Perhaps some sort of screw...
Michael Shumate wrote:About 25 to 30 years ago I designed a brochure (I'm a graphic designer) for a start-up company headed by a former aeronautical engineer who used to specialize in aviation transmissions (I didn't even know that airplanes had transmissions). He said his former enemy was always the heat generated by two sets of veins, paddles, blades rotating at different speeds. It made dangerous amounts of heat at the high RPMs that those engines operate at. After retiring he realized that the same enemy could be used to generate heat directly from motion for domestic use. When I was doing the brochure for him he had developed a system that used an agriculture style windmill with a vertical shaft that transferred the motion of the windmill down to a transmission box buried in the ground. The box was basically a transmission box with one set of blades immobilized. The friction in the transmission fluid made lots of heat that was transferred to water via a heat exchange coil into a tank. The pipes from the windmill to the house had to be well insulated but that was the gist of the whole concept.
I moved from there shortly after doing the brochure so I don't know if the company ever succeeded but I'd love to find out if any such set-up is commercially available. Failing that, I'd like someone's ideas on converting a transmission into a heat generator.
What say ye?
Jonathan 'yukkuri' Kame wrote:Makes me think of this, though I am prone to disbelieve the over unity claims.