Rocket mass stoves

[KBCraig]

Here's an interesting stove design. It uses the "rocket stove" principle for complete combustion, burning a small amount of fuel at very high temperatures, coupled with a thermal mass design to gently release the heat from a 4 hour burn, over 8-12 hours.

http://en.wikipedia.org/wiki/Rocket_mass_heater

Here's a good page with lots of videos, so you can really see how they work.

http://www.richsoil.com/rocket-stove-mass-heater.jsp

The tinkerers among you will probably think of modifications that could make it easier to clean (although there's not much to clean, with such high combustion efficiency).

And here's a very nice permanent installation.

http://ilovecob.com/archive/living-with-the-rocket-stove

[KBCraig]

Now, if we could just figure out a heat removal system that's so easy and efficient, for use in Texas...

[Russell Kanning]

it's called summering in NH

[Russell Kanning]

interesting
our woodstove at the hoyt farm worked best with full airflow, but didn't have all the nice thermal mass. We did have nice clean emissions. it was very normal to only see heat waves out the top. I enjoyed driving around town and noting how much cleaner ours was.
I don't quite see how these would be better than a normal masonry stove for the combustion part of the operation. I also like the idea of piping in the fresh air from outside and having the ability to shut of the intake and exhaust air after the burn.

[KBCraig]

I don't quite see how these would be better than a normal masonry stove for the combustion part of the operation. I also like the idea of piping in the fresh air from outside and having the ability to shut of the intake and exhaust air after the burn.

I don't think it would be more efficient than other super-efficient designs, but the J shape makes it self-feeding without power. The combustion always stays in one small chamber, then the re-combustion of the superheated gases takes place in the barrel.

Yes, outside air is important, especially if you've built a tight house.

[Russell Kanning]

after watching the video, I like the idea in many ways .... especially since they were able to build their own burn chamber

but not having control of how much air goes in or from where seems funny to me
it also seems like most of those designs wouldn't want to draw at the beginning

[KBCraig]

At worst, you'd have to "prime" it by going outside to light a piece of paper in the flue.

[MaineShark]

Rocket stoves are very cool.

Most of the designs are from areas that are much drier than NH.

They still work, but you have to be aware of the materials you use; if you just follow "the book," you may end up with something that crumbles, the first spring.

So follow the theory, but adapt the materials.  I'm seriously thinking of one for my next place.

Joe

[KBCraig]

Yeah, I don't think you'd have good luck with cob in NH. I wouldn't even use it here.

[Lloyd Danforth]

When I first saw one, I thought about adapting a Rocket Stove (90 degree turn, fed with sticks) to a Hahsa Outdoor wood burning furnace.
However, in most of the youtubes I've seen concerning Rocket stoves, they are being used to cook, and ostensibly someone is round to shove the sticks in.
I'm not sure how that would work with a furnace unless it was in a work area where you'd be around to feed the fuel untill the water or antifreeze to get to temperature.

[MaineShark]

When I first saw one, I thought about adapting a Rocket Stove (90 degree turn, fed with sticks) to a Hahsa Outdoor wood burning furnace.
However, in most of the youtubes I've seen concerning Rocket stoves, they are being used to cook, and ostensibly someone is round to shove the sticks in.
I'm not sure how that would work with a furnace unless it was in a work area where you'd be around to feed the fuel untill the water or antifreeze to get to temperature.

If properly designed, it will self-feed.

The same basic feed design was used in Professor Hill's excellent (for their time, anyway) wood-fired boilers.

Joe

[Lloyd Danforth]

The guy from 'The Music Man'?

[MaineShark]

The guy from 'The Music Man'?

No.

Joe

[Russell Kanning]

you could have the entrance to the stove be on the outside and have a huge cement funnel leading to the mouth .... with a whole winter's worth of wood or coal heading down in

[MikeforLiberty]

I'm planning a rocket mass system for my tiny house. Does anyone know of other rocket mass heaters built in the NH area? I need to calculate heat loss for the 'house' and the amount of thermal mass needed. I'm think about a system build below the floor run from outside. That could be inconvenient but if I had enough mass that it might only need a burn once a day or less, it could be liveable.

I need to contact this guy...
http://www.raycotechnologies.org/hot_water_storage_systems.htm
pretty interesting stuff.