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greenhouse with a rocket mass heater vid

paul wheaton
steward

Joined: Apr 01, 2005
Posts: 14163
Location: missoula, montana (zone 4)
    ∞
I just now uploaded it!

http://www.youtube.com/watch?v=qtFvdMk3eLM


sign up for my daily-ish email / rocket mass heater 4-DVD set / permaculture playing cards
Travis Philp
volunteer

Joined: Dec 28, 2009
Posts: 951
Location: ZONE 5a Lindsay Ontario Canada
    
    2
Looks like a great system. Would one be able to load it up with wood before bed and have it still producing heat by the morning? Or is there enough residual heat stored by the thermal mass to carry plants through the night despite lack of fire?


http://www.greenshireecofarms.com
Zone 5a in Central Ontario, Canada
Jami McBride
volunteer

Joined: Aug 29, 2009
Posts: 1760
    
    3
Paul it's soooo frustrating not being able to hear what is being explained due to the bad mic.
Is there anyway you can do a voice over and add the missing dialog?  Or add it via type?

I'm very interested to hear what is being said.

Anyway, looks like this film was this summer, do you have the rest where they finish the project?  Will you be posting that as well? 

Thanks for the posting
ronie dee


Joined: Mar 04, 2009
Posts: 584
Location: Cosby MO
    
    1
Amazing nothing short of Amazing -  Building the structure around the RMH! ...I can't wait for part II...

When i worked in a greenhouse ,many years ago, they 'sterilized' the soil beds by putting a tarp over them and (using great amounts of energy) running hot steam over the soil.  I have been wondering if the rocket exhaust could be diverted over the soil beds to get the same effect? 

The greenhouse would have to be avoided until the fire burned out and then left closed -say overnight- then open up to get fresh air in - then revert the rocket exhaust back outside.

Sometimes the answer is not to cross an old bridge, nor to burn it, but to build a better bridge.
paul wheaton
steward

Joined: Apr 01, 2005
Posts: 14163
Location: missoula, montana (zone 4)
    ∞
There have been so many comments on it at youtube, that it made the youtube science and technology "most discussed" list!

If we get 15 more comments, it will move to page 1 of that list!

    http://www.youtube.com/paulwheaton12#p/u/0/qtFvdMk3eLM


paul wheaton
steward

Joined: Apr 01, 2005
Posts: 14163
Location: missoula, montana (zone 4)
    ∞
Travis Philp wrote:
Looks like a great system. Would one be able to load it up with wood before bed and have it still producing heat by the morning? Or is there enough residual heat stored by the thermal mass to carry plants through the night despite lack of fire?




(a great question to ask on youtube, wink, wink, nudge, nudge)

The great thing about the RMH is that you build one small fire and the heat lasts days after the fire has gone out.

paul wheaton
steward

Joined: Apr 01, 2005
Posts: 14163
Location: missoula, montana (zone 4)
    ∞
Jami McBride wrote:
Paul it's soooo frustrating not being able to hear what is being explained due to the bad mic.
Is there anyway you can do a voice over and add the missing dialog?  Or add it via type?

I'm very interested to hear what is being said.

Anyway, looks like this film was this summer, do you have the rest where they finish the project?  Will you be posting that as well? 



I checked in with the folk that own that property.  They greenhouse is gonna get built this spring.

I went and spent an hour or two adding "talk bubbles" to compensate for the lousy sound.  Try it again.


paul wheaton
steward

Joined: Apr 01, 2005
Posts: 14163
Location: missoula, montana (zone 4)
    ∞
ronie wrote:
Amazing nothing short of Amazing -  Building the structure around the RMH! ...I can't wait for part II...

When i worked in a greenhouse ,many years ago, they 'sterilized' the soil beds by putting a tarp over them and (using great amounts of energy) running hot steam over the soil.  I have been wondering if the rocket exhaust could be diverted over the soil beds to get the same effect? 

The greenhouse would have to be avoided until the fire burned out and then left closed -say overnight- then open up to get fresh air in - then revert the rocket exhaust back outside.



Wow .... I never thought of sterilizing the soil.  How weird. 

I would think there would be a way - but ... this is a new thing to me.

Travis Philp
volunteer

Joined: Dec 28, 2009
Posts: 951
Location: ZONE 5a Lindsay Ontario Canada
    
    2
ronie wrote:
I have been wondering if the rocket exhaust could be diverted over the soil beds to get the same effect? 


Unless the soil shows signs of infection visible via the plants I'm not sure why you'd want to sterilize but... I'm pretty sure water mixed with hydrogen peroxide at a certain ratio will sterilize the medium and require a lot less effort. I've pots of soil get moldy at the top before and cured it with a mix of 2% strength hydrogen peroxide at a ratio of 10-1 (water-peroxide) which is not conclusive but indicates to me that it'd work for anything anaerobic at least...
paul wheaton
steward

Joined: Apr 01, 2005
Posts: 14163
Location: missoula, montana (zone 4)
    ∞
Now on page 2 of science and technology "popular"
Jordan Lowery
volunteer

Joined: Sep 26, 2009
Posts: 1526
Location: zone 7
    
  11
awesome video paul, i was planning on doing this anyways. but that just sealed the deal. the way i was thinking about it the heat stored in the thermal mass would last well overnight, and most likely into the next day/night depending on the setup. specially if its a solar greenhouse and not just a hoop greenhouse or the normal box ones. thanks for the video i cant wait to build one myself.


The ultimate goal of farming is not the growing of crops, but the cultivation and perfection of human beings. - Masanobu Fukuoka
Matthew Fallon


Joined: Jan 07, 2010
Posts: 307
Location: long island, ny Z-7a
    
    1
amazing how much attention it's gotten in 13 hours
you've got quite a few followers!
i learned soem new things from this one, such as manipulating the 'heat taurus' up or down by varying the height of the barrel above the heat riser.

one thing that might concern me is the small amount of wood that can be added in 1 go, seems like  it'd  need supervision to be continuously adding wood?
of course i don't actually know if thats a warranted concern

something i'd like to see in a RMH,is a feed tube large enough to accommodate a standard-ish sized 1/4'd piece of firewood,or  to have an equivelant amount of small pieces self-feed into it on its own,say like a tube made of wire-fencing (as to not impede air-flow) that can be placed on the feed tube once the fire got going.

i'd also be interested in ways of using up all the wood-shavings created by by lathe turnings for feeding the RMH, although right now they do make really nice plant bedding and dry material for my compost.


Baldwin Organic Garden Share  Our home-based garden cooperative.  Tribal Wind Arts Rustic Furniture  & Artisan-Craftwork from reclaimed suburban trees
Ernie Wisner
volunteer

Joined: Oct 16, 2009
Posts: 788
Location: Tonasket washington
    
  23
tribalwind if you are even close to some one who has a rocket stove stop by and bring dinner for all. it would be educational. the stove does not need to be loaded any more than you would load a box stove (undamped down).

in ours here in the house i burn one log five inches across for several hours. i just give it a twist every hour or so. best wood for this is alder or myrtle by the by.
Ours is a 6 inch system and i find that i load about every hour. i have cut the wood to 12" long so we can put the lid on. if i use longer wood it takes longer to burn. so it is adjustable.

the depth of the feed is about 9" if you put a bucket around it you can go 16" or so. wood hangs up in a wire cage so we try to discourage those. if i am sitting on the bench and working or reading i do put long wood in up to about 3 feet. however you do have to monitor it. not hard to do if you are sitting on it 

if you want to use shavings you can do a slow feed or press them into briquettes/ logs. i would make them short just in case they burn real fast. for a binder to make the logs you might try starch instead of glue. the stoves are set up for biomass fuel so using a petro or oil derived glue would be a bad thing. 


Need more info?
Ernie and Erica
Wood burning stoves, Rocket Mass Heaters, DIY,
Stove plans, Boat plans, General permiculture information, Arts and crafts, Fire science, Find it at www.ernieanderica.info


paul wheaton
steward

Joined: Apr 01, 2005
Posts: 14163
Location: missoula, montana (zone 4)
    ∞
Look!  It's Ernie!  The star of the show!

Jami McBride
volunteer

Joined: Aug 29, 2009
Posts: 1760
    
    3
Thanks for the bubbles Paul, that's much better....

Matthew Fallon


Joined: Jan 07, 2010
Posts: 307
Location: long island, ny Z-7a
    
    1
Hi Ernie, thanks for all the info youve provided here and in the youtube comments.

you're right i definitely need to experience one/more firsthand
l i doubt there is anyone near me with a RMH. the codes here are probably way too stringent for one. look up 'Suburban hell-scape' and it'll say "see long island" . what i'd love to do is get one made in my detached garage workshop that i can take out in warmer months.(whole shop isnt permitted anyway) currently using cast-iron woodstove.

so hourly attending ,albeit very minimal,still seems like a lot of babysitting? the twisting is needed though hm. and at night you just let it go out and the mass is warmed enough to last.?

i work a lot with bamboo ,mostly flute-making..it seems like it'd be the perfect fuel for a RS/RMH. it's thin,dense,dries fast,burns great and very hot,plentiful & renewable (fastest growing plant on earth).
cut at maybe 36"+ lengths,it'd self-feed for a long time then aye?,split up it would condense to store inside really well too...splitting is necessary anyway as it'd explode if burned whole(between the nodes) it use to be used like that to scare animals away from camps back in asia.
Ernie Wisner
volunteer

Joined: Oct 16, 2009
Posts: 788
Location: Tonasket washington
    
  23
if you have 8" of mass around the ducting and you heat it up you have 8 hours of heat stored. best way to do this is to heat for an hour a day it accumulates heat in the mass and you just keep it up. best way to think about it is the thermal mass as a battery that you are charging up with a trickle charger.

heat enters the mass at one inch an hour +/-  and discharges from the mass at the same rate so you can "set" how many hours of heat you want by the thickness of your mass.

the one planned for my shop will be my worry chair; I like to build wood boats and a worry chair is an essential part of trying to get your head around some of the compound curves .

bamboo does work very well in the stove; it burns very fast so you would have to load it often. not too arduous a job as it takes just a moment and in a shop you could probably use the break. not to mention it will keep your tea hot. 
Joel Hollingsworth
volunteer

Joined: Jul 01, 2009
Posts: 2103
Location: Oakland, CA
Great video!

Paul, does Youtube allow you to edit the bubbles? I think you meant "heat torus."

It's easier to visualize what's going on there in the case of air moving through water (rather than hot air moving through cold air). Similar fluid dynamics apply, but toroidal bubbles are more visible.

http://bubblerings.com/bubblerings/media.cfm

Some discussion from the same site:

http://bubblerings.com/bubblerings/faq.cfm#vortex

Ernie: Any merit to using mucilage, rather than starch, as a briquette binder? I understand psillium husk or acacia sap might be cheaper than flour paste in some parts of the world, and the result might be less perishable.

Edit: clearer wording


"the qualities of these bacteria, like the heat of the sun, electricity, or the qualities of metals, are part of the storehouse of knowledge of all men.  They are manifestations of the laws of nature, free to all men and reserved exclusively to none." SCOTUS, Funk Bros. Seed Co. v. Kale Inoculant Co.
Ernie Wisner
volunteer

Joined: Oct 16, 2009
Posts: 788
Location: Tonasket washington
    
  23
I would think either would work pretty well for a binder; both should burn well once ignited. I believe the mucilage might need a very long drying time. I'll have to test it and make sure.

now you done it i have to go make a press so i can give it a try. 
ronie dee


Joined: Mar 04, 2009
Posts: 584
Location: Cosby MO
    
    1
You guys realize that the sun is going to heat your RMH also and that makes it burn even less wood...now just figure out how to make it black in color to absorb more sun.
ronie dee


Joined: Mar 04, 2009
Posts: 584
Location: Cosby MO
    
    1
I've made 3 comments on youtube, but so far only one has shown up... must be doing something wrong?
Ernie Wisner
volunteer

Joined: Oct 16, 2009
Posts: 788
Location: Tonasket washington
    
  23
black iron oxide plaster. and yes i do understand that the sun will heat the stove. its planned for in the case of this stove as is a simple bypass so you dont have to heat the bed.

yes something is going on with youtube postings. i have written two responces and nether was posted. its rather pissing me off.
Erica Wisner
volunteer

Joined: Feb 10, 2009
Posts: 682
Location: Okanogan Highlands, Washington
    
  78
tribalwind wrote:
Hi Ernie, thanks for all the info youve provided here and in the youtube comments.

you're right i definitely need to experience one/more firsthand
l i doubt there is anyone near me with a RMH. the codes here are probably way too stringent for one. look up 'Suburban hell-scape' and it'll say "see long island" . what i'd love to do is get one made in my detached garage workshop that i can take out in warmer months.(whole shop isnt permitted anyway) currently using cast-iron woodstove.

so hourly attending ,albeit very minimal,still seems like a lot of babysitting? the twisting is needed though hm. and at night you just let it go out and the mass is warmed enough to last.?


I don't know long island codes.  In Oregon (under DEQ), there are some exemptions for things like antiques, sole heating device, sole cooking device, and 'recreational warming fires.'  Outdoor wood-burning setups are relatively easy to arrange, but indoor ones fall under all kinds of building code, including foundations and heat-shielding.  Not sure what the code would be for an outbuilding or shop.

We're going to be in the Toronto area in May; that may be the closest RMH workshop to your area this year, and we'll be building at least one full-scale mockup as well as some other devices to delight the pyromaniac.  www.naturalbuild.ca

It takes much less babysitting than a fireplace, more or less like a woodstove when it's going.  Like any fire, you don't want to leave it unattended - and it won't turn itself on and off while you're on vacation like a furnace. 

The difference is that with a woodstove you need to keep it going, or smouldering, most of the time - and with a mass heater, it will stay warm for anything from hours to days after one brief fire session.  So it's pretty low-maintenance as DIY wood heat goes.

Running it on split bamboo, I think you'd be feeding it more often, but you could still get a fair amount of heat from relatively short periods of attention.


Play with nature, make nifty stuff:
www.ErnieAndErica.info
paul wheaton
steward

Joined: Apr 01, 2005
Posts: 14163
Location: missoula, montana (zone 4)
    ∞
So, my impression is that once you get on the "popular" page, your video "goes viral".  But I left a couple of ingredients out that might be the key.  I thought they were stupid and wouldn't matter.  Apparently, I'm wrong.

1)  Keep the video well under a minute

2)  At precisely halfway through, it must be an image of a hot babe, preferably with cleavage.  Instead, we have Ernie's leg near some bricks and a stove pipe.  So if Erica had bent over to point out that the fire was burning sideways right there, this might have filled this ingredient.

3)  Use a title that has two different meanings.  One meaning being appropriate and another meaning that gets the completely wrong idea when combined with the cleavage.  So rather than calling it "greenhouse rocket mass heater", call it "sultry rocket heat" or some such ... wait ... I remember that the title has to have shock jock value, so maybe "sultry rocket heat?  WTF?!!!"

Forgetting all that claptrap:  we DID accomplish the first step.  The hard part.  We got onto the page for the general audience of youtube.  If you go to youtube right now, click on "videos" and then "science and technology", you will see it right there. 

And, I guess the reason it has only 1500 views instead of 150,000 is that I left out the three ingredients from above. 



In four hours it will slide off the "today" list. 

I think this was a very educational experience.  And I appreciate everybody putting in so much effort to try and get this on its feet! 

Thanks!

Ernie Wisner
volunteer

Joined: Oct 16, 2009
Posts: 788
Location: Tonasket washington
    
  23
it aint over till its over.
paul wheaton
steward

Joined: Apr 01, 2005
Posts: 14163
Location: missoula, montana (zone 4)
    ∞
Go man go!

It looks like it has about 1600 views now. 

And it looks like you fixed your problem with posting there.

Ernie Wisner
volunteer

Joined: Oct 16, 2009
Posts: 788
Location: Tonasket washington
    
  23
not just my problem, other folks had the same this morning. its just an irritant on a day when the weather is fluctuating like a crack fiends yoyo.
Ernie Wisner
volunteer

Joined: Oct 16, 2009
Posts: 788
Location: Tonasket washington
    
  23
ok We dont seem to be able to compet with the new apple products hitting the market.

Have to twist Jobs ear about it for fun.

paul wheaton
steward

Joined: Apr 01, 2005
Posts: 14163
Location: missoula, montana (zone 4)
    ∞
2300 now. 

Yeah, go tell jobs to get some traffic to your video! 

Bradon Wesche


Joined: Dec 20, 2009
Posts: 38
paul wheaton wrote:
I left out the three ingredients from above.


Here is a permaculture video with all the magic ingredients:

http://www.youtube.com/watch?v=UXGlB1kGO5E&feature=grec


http://www.bradonw.com
Matthew Fallon


Joined: Jan 07, 2010
Posts: 307
Location: long island, ny Z-7a
    
    1
Bradon Wesche wrote:
Here is a permaculture video with all the magic ingredients:

http://www.youtube.com/watch?v=UXGlB1kGO5E&feature=grec


hah, i've seen that one before (i guess it works!)

btw bradon, cool site. LOVE love love sketchup.i've used autocad for the past 15+ years
professionally,but hardly touch it anymore for my wood projects.
rebecca m.


Joined: Feb 13, 2010
Posts: 5
Location: waldron, WA
Thanks for all the great info !  I'm new to this forum, so please forgive any repeat questions, as I haven't yet read everything there is to read...

I'm currently designing a rocket mass heater for a propagation greenhouse here in NW Washington.  The greenhouse is 24'x 12' and the intended purpose is to provide bottom heat for starting flats of vegetable and flower seedlings in late winter/early spring.  The greenhouse is not an earth sheltered design as in the video, but is a solar greenhouse with insulated north wall and dbl. wall poly for glazing on the rest.  I am off grid and had considered setting up a system with hot water tubing on the benches, with wood as the primary heat and propane as a back-up, but once I learned of the rocket mass heater idea, decided to go that route.  And now that I've discovered this forum, I'd like to get as much input as possible before making too many mistakes in the design.

I have lots of questions, but the one most pressing at the moment is about how long I can run the horizontal stovepipe through the thermal mass and still expect to get a draw and/or take advantage of any heat.  I originally thought to run one straight pipe the length of the greenhouse, ~20' or so, but am now wondering about turning the corner and running it back the length to exit near the stove, for a length of about 40'.  Is that too  long?  I haven't seen any examples of RMHs with a run quite so long... 

Any ideas about the maximum length of pipe would be much appreciated!  And any other ideas about using a RMH in this context...
paul wheaton
steward

Joined: Apr 01, 2005
Posts: 14163
Location: missoula, montana (zone 4)
    ∞
I was holding out figuring that other folks would answer this. 

40 feet with one 180 degree turn should be just fine.

paul wheaton
steward

Joined: Apr 01, 2005
Posts: 14163
Location: missoula, montana (zone 4)
    ∞
Bradon Wesche wrote:
Here is a permaculture video with all the magic ingredients:

http://www.youtube.com/watch?v=UXGlB1kGO5E&feature=grec


Yup. 

Are all of their videos like that? 

I suppose one could blame men for being such horndogs, but my impression is that women click on that sort of thing more too.  After all, take a look at women's magazines in the safeway checkout. 

But!  This is now devolving into something better suited for the MD forum.



ronie dee


Joined: Mar 04, 2009
Posts: 584
Location: Cosby MO
    
    1
paul wheaton wrote:
I was holding out figuring that other folks would answer this. 

40 feet with one 180 degree turn should be just fine.




The reason that i am afraid to attempt an answer to any question like this is because too many people are wanting to try too many different things in the construction of their RMH. (And Erika, Ernie and Paul have more practical experience that i do.)

Anyone who wants to experiment or change any of the specs that Paul, Ericka, Ernie or Ianto have given... can easily run into problems that could have dire consequences.

A question of, "Can i get away with _ _ _ _ _ ..."  -presents many variables that can't easily be answered without much more info.

How much of a vertical chimney is planned at the end?  How hot will the exhaust temp be?  Does the person have any experience burning wood? Are they planning to follow the basic (proven) design or are they going to use different materials and clearances?
Are they planning to put a whirly-bird at the end and draw a millivolt of electricity? 
rebecca m.


Joined: Feb 13, 2010
Posts: 5
Location: waldron, WA
Thanks for the succinct answer, Paul.  I posted the the question about the maximum length of horizontal flue pipe because I have yet to see examples of any quite that long, although it's been alluded to that "more than 30'" works fine.  I suppose I'll give it a go with 40'.

In answer to the questions from Ronie, i'm planning to follow all the specs for an 8" system described in the Rocket Mass Heater book.  I've also been pouring through the available video/photos/description I've found on the net. It seems clear there will have to be some playing around with the height of the vertical chimney at the end.  I know there are lots of variables, and do intend to stick to the tried and true for the most part.  That is also why I thought to ask a question on this forum. 
"The person" does have experience burning wood, but never using a rocket stove. 
It hadn't occurred to me to put a whirlybird at the end.  Is that a suggestion?

ronie dee


Joined: Mar 04, 2009
Posts: 584
Location: Cosby MO
    
    1
bluemoon wrote:
It hadn't occurred to me to put a whirlybird at the end.  Is that a suggestion?



hahhahaha no I think the whirlybird would be better as a lawn ornament..
But for some reason the idea of putting a wind turbine in the exhaust of the RMH keeps coming up.

Ask as many questions as you can think of and maybe Ernie or Erika will have time to get on and offer suggestions...

The one thing that is different from a regular wood stove is that the vertical heat riser (inside the barrel) pushes the exhaust down, around and out. (It is much similar to the behavior of fluid in a closed system like a water pump.) In a regular wood stove the rising hot exhaust gasses and smoke go up and out with something we used to call the 'chimney effect.'

So a regular wood stove does well with a long upward riser at the end. But the RMH can do well without much of a vertical run (at the end) In fact I have already asked and Erica said that i could run the exhaust downward... Getting the exhaust out to a place that will cause no harm is very important as it is with any combustion system.

In your greenhouse the exhaust gases  (cooled) would not harm plants but could be deadly to animals. There are properties of exhaust gasses, that could be beneficial for  plant growth and pest control, but could be dangerous to oxygen breathers.
john smith


Joined: Aug 14, 2010
Posts: 70
Location: western u.s.
paul wheaton wrote:
I just now uploaded it!
http://www.youtube.com/watch?v=qtFvdMk3eLM


Lowering the riser inside the barrel
[quote author=Ernie in the video]
"will have the effect of moving the heat taurus down .. that would mean less instant heat up in the top of this, and more heat in the bed."

If reducing the height of the riser puts more heat in the bed, then getting rid of the riser completely,
would put the most heat in the bed.  Ernie is basing that on the total heat being the same.  However, the higher the riser (heat taurus) the more complete burning of the wood, and therefore the greater total heat.

What we know:
higher riser = more immediate heat & more total heat
lower riser = less immediate heat & less total heat

My understanding is that a higher riser has two purposes.
1)  to pull heat faster from the burn,
according to Ernie, this has the cost of producing less heat in the bed;
2)  more complete burning of the fuel.

As a higher riser results in more complete burning of the fuel, there is not only more immediate heat, as the barrel gets hotter before the heat moves into the beds, and there is also more total heat.

In absence of testing, because the total heat is greater with a higher riser, it seems to me to be unknown if a higher riser puts greater, less, or the same heat to the beds.

As there is more total heat, especially more immediate heat, the heat in the beds could be the same or increase.


how to convert a chest freezer to a fridge

Where liberty dwells, there is my country. -- Benjamin Franklin
Ernie Wisner
volunteer

Joined: Oct 16, 2009
Posts: 788
Location: Tonasket washington
    
  23
please read the book the heat riser does much more then just place the heat at a random point in the barrel
john smith


Joined: Aug 14, 2010
Posts: 70
Location: western u.s.
Since seeing the Portland rocket heater video a few days ago, I've noticed the RMH's reach 200 to 600 at the top of the riser, compared to MASONRY heaters that reach a temperature of 1200 to 2000 degrees. Big difference. 

That's probably why people can't get a straight answer to questions.

I would not call the RH an improvement.

The RH is easier to build, but the heat output is much less than a masonry heater.
 
 
subject: greenhouse with a rocket mass heater vid
 
cast iron skillet 49er

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