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Lina Joana

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since Jan 31, 2015
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Recent posts by Lina Joana

So I am not an expert in mushroom cultivation, but I have failed to grow them on several occasions. Based on my failures, I don’t think those chunks have enough bark on them to do well as logs. So you problem may have not been freshness, but too much exposed grain, giving other fungi a chance to colonize after inoculation.
What that suggests to me is that you might have good luck chipping, and inoculating with wine cap (king stropharia) mushrooms in an outdoor bed. Wine caps are vigorous enough to do just fine on unpasteurized wood chips.
For spores: Yes, they will survive anaerobic fermentation. But then, spores survive boiling as well: thats why water bath canned green beans are a no no. So surviving spores are probably not the issue. Likewise for anaerobic fungi, which are mostly found in the gut - maybe if those logs had been rolling around in cow dung you should worry…
The main question I have would be the changes made by the anaerobic fermentation. Without oxygen, the microbes will produce all kinds of fun alcohols and acids. Since you can’t  keep it sterile during inoculation, will these extra food sources encourage other microbes to settle down? Or discourage your preferred fungus? I could see this being a problem for lions mane, which is pickier, vs vigorous and versatile oysters. Or maybe that is backwards, and lions mane loves to eat anaerobic leftovers!
If you try it, please post the process and results- I am super curious!
4 hours ago
The Rich soil faq is fine. To anyone stumbling on it, it is a random web page that is throwing out numbers that don’t sound believable, with no references to back them up.
Take the answer to the “10 times more efficient” question. Ok, so the 75%+ efficiencies come from optimum lab conditions. But where do the rest of the numbers come from? Who has established that a really good operator who is burning dry wood can only get 35%? How do we know that “most” people use their wood stoves at 3-15% efficiencies? The 1/10th numbers come from “people we know”… who are these people, and what kind of stoves were they using? Did they actually know how to use them? Why should I give any credence to the people some guy on the internet knows?
Finally, these questions keep coming up because the experiences are not universal. There has been mention on this thread of the couple who is using around half the wood they used to. Nice savings, but not even close to 1/10th, and doesn’t heat the far out rooms. So there is a lot of conflicting information (all of which is actually true, depending on the situation) and it all starts to sound like hype.
2 weeks ago

Julie Reed wrote:

Lina said- "Your friend’s experience is compelling- it may be that the 1/10 number does come from people not using their stoves properly - it is easier to toss big logs in that will smolder, green or not, and harder to maintain a clean burn."

You can't blame poor efficiency on the stove, if people are using it improperly. That would be like saying X brand cars claim 30 mpg, but only get 14 mpg, but it's really because the drivers are riding the brake pedal.

Oh, I agree!
So maybe, bringing this thread back to the question of “what is keeping people from getting excited about the concept and sharing it with others to make it go viral”:
1) some of the info out there seems to good to be true, and at least some people have found it to be so - an rmh uses half the wood of a properly used super efficient wood stove, not one 10th, at least in some houses.
2) The downsides to implementation are - may need to remodel your house to take the weight, you need much thinner pieces of wood to fit in the jtube (more time splitting), and you need to spend several hours constantly feeding it during the burn.
3) There are regulatory barriers, and the fact that there isn’t an obvious path through those makes it seem like a risky and experimental technology- not what you would encourage your neighbor with an old furnace to install.

In sum, if people don’t feel comfortable sharing it because they aren’t sure its real, it will not go viral.

Unfortunately, it will most likely take time. More heaters are getting installed each day, which means more people will see them. Eventually, there will be enough around that pros will feel comfortable building and even recommending them. But I don’t know how to speed that up.
2 weeks ago

Julie Reed wrote: I realize that some of the heat from a woodstove goes up the pipe. However, my understanding is- that is factored into the efficiency rating. Thus the 50-70% is actual realized heat from the wood burned

Huh - that was not my understanding, but I may be totally off base. Do you have a source with a good description of how they do the tests for stove efficiency?
Your friend’s experience is compelling- it may be that the 1/10 number does come from people not using their stoves properly - it is easier to toss big logs in that will smolder, green or not, and harder to maintain a clean burn.
2 weeks ago

Anne Miller wrote:Now we are getting somewhere:

Lina said, "It is the mass - the large bench, and all the cob surrounding it the barrel- that is so heavy.

Do all RMH use cob?

Well, there is the pebble style, which uses pebbles instead. There are masonary heaters which use rock and brick. Probably some rmh which do so too.
The point is that you need a material dense enough to pull 90% of the heat out of the fire and release it over several days. In order to do that, it has to be heavy. Anything light will insulate the pipes, making them carry heat out of your house instead of storing it.
You can have a rocket heater, without the mass. I use one in a tiny house I built on my parents land. It heats up fast with twigs and scraps and has a nice clean burn. But it gets cold as soon as it goes out, meaning you run it constantly whenever you want heat. It gets frosty in there at night… noy what you want when trying to heat a whole house, and not much better than a modern wood stove.
2 weeks ago

Julie Reed wrote:
Most woodstoves are at least 50% efficient, so logically the most you could possibly improve on that would be to 100%, or half the wood, not 1/10th. My backyard is many acres, so I suppose I could maybe heat with all my twigs, but overall that's unrealistic for the average homeowner. Heating a house needs a certain number of BTUs regardless of where they come from. In cold areas, the minimum is probably going to be a full cord of wood, depending on many other factors like size of dwelling and weatherization. I recently spoke with a couple who just added an RMH to their fairly new (thus energy efficient) 1200 sf home in 2020, when they had free time due to covid shutdowns. The style is ranch, with a rectangular layout of 30x40. Their RMH is centrally located, and yet even with fans they cannot get adequate heat to the rooms on the ends during '20-30 below' nights (which there are many of, for anyone in northern states...

First off, thanks for sharing your friends experiences! The more solid examples we have the easier it is to get a sense of how they work.

I want to try to take a crack at the 1/10th the wood thing, because I have never heard a clear explanation of it, and it was mindblowing when I thought about it.
A regular stove is 50-80% efficient. You will hear disputes on whether the certification figures reflect the real world usage. They probably don’t, but this is small potatoes. The real question is, what is that number referring to?
The answer is that it is measuring the percentage of energy in the wood that is converted into heat. This is NOT the same as the heat that is dumped into your home, because plenty is carried out with the flue gasses. How much is a number I have trouble finding, but I think that upon exiting the building, flue gasses from a standard stove are something like 300-900 degrees, while the fire should be 500-1100 degrees to avoid warping the iron. So you are losing quite a lot if heat out the chimney: I am not sure how to calculate the percentage of total heat produced without knowing what the airflow is. In comparison, a masonary stove or an rmh are supposed to reach more like 2000 degrees in the firebox, and the flue gas should be less than 200. So 90% of the heat liberated from the wood stays in the mass, to be radiated into your home.
So, 1/10th the wood may not be as far off as it seems at first.
2 weeks ago

Anne Miller wrote:

Dc Stewart wrote:Re: comparison of RMH weight to the weight of a loaded freezer

Can you tell me what is inside a metal barrel that weighs so much?

It is not the metal barrel that is heavy.
It is the mass - the large bench, and all the cob surrounding it the barrel- that is so heavy. Those benches in all the pictures are either cob packed around a looping exhaust pipe, or a box filled with rocks. All of that heavy stuff is what holds the heat.
I don’t know what makes something go viral. I just know what I feel comfortable sharing with my friends. And I am not going to tell them that they can build a heater for 100 bucks when the reality is very different.
2 weeks ago

Anne Miller wrote:

Lina Joana wrote:Weight. I believe the fisher price house needed extra support put in. Most standard houses do not have a floor that can take the mass without reinforcement.

I feel that is just an excuse to justify that someone is too lazy to build one or just too tight to spend the money.

The only excuse that I might accept is that their insurance company will not approve and wants to exclude coverage.

If the floor of a manufactured home can have extra support added so can a standard home.  Look at the heavy freezers full of food that can be justified. I bet those weigh more than an RMH

Regarding the weight, I believe someone else answered that, but - my understanding is that yes, the mass of an rmh is a LOT heavier than a full chest freezer, unless you are storing cob or rocks in said freezer. I am sure someone on this thread could tell you the pounds per square foot number you need your floor to withstand.

Regarding the ability to make renovations- sure, on most houses it is possible. In some, it might involve getting giant beams into a crawl space or basement. In others, it might involve ripping out drywall ceilings, possibly walls if the stringers were at their weight limits. It is probably easier to do it on manufactured house, since their supports are usually accessible from the outside.
The bulk of the population would want to hire a structural engineer to make those calculations for their house, after finding a reliable number for the pounds per square inch load of a rocket mass heater at its heaviest (i.e with wet cob). Once they knew what had to be done, they would probably hire a contractor to make the modifications. In my neck of the woods, all of that would probably cost around $6000-10,000. Before even beginning the build.
I suppose you can call an unwillingness to embark on that journey as being too lazy to build one and too tight to spend the money. I certainly was, much as I wanted one. And, I am reluctant to talk it up to my friends and acquaintances as a real option, because I know that if they live in a standard house, installing one will probably not be “cheap” - not in the hundreds of dollar range that the build itself would cost, anyhow.
2 weeks ago

Anne Miller wrote:I keep reading in this thread and in another something thread something like this statement:

Rachel said, " Implementation in average existing housing stock prevents people who learn about it from moving forward.

While I admit I have not built one though I believe if one can be built in a tent or even the Fisher Price House why not put one in a regular home?

Weight. I believe the fisher price house needed extra support put in. Most standard houses do not have a floor that can take the mass without reinforcement.
2 weeks ago

paul wheaton wrote:Maybe we need a massive rmh misinformation/excuse FAQ - so that all the little bits that block people from learning about rmh can be resolved.

Sure, you can try. But I still think it comes down to credibility. Personally, I find you credible, even though we’ve never met, and I am not aware that you have formal training in engineering or other fields that teach you how yo design a stove. I believe that you have experimented and built enough that your info is good.
But if I want to share it, how do I communicate that? “There is this guy on the internet that says…” will my friends agree? Or will I lose credibility with them for promoting this crazy guy on the net who claims you can heat your whole house with junk mail?
I truly think this is a barrier to having things go viral. At this point, everyone knows you can’t trust everything you read on the internet. How is the rocket mass heater stuff credible to people who have only ever seen them online? And let me say - in general, I consider open forums less credible than an official looking informational page. Permies is an exception for me, but not my non permie friends. So threads will likely not be used as credible info.
I suggest that using the markers most people consider credible, such as engineer stamps, code guides, and warranties by professional installers, would be one way of making it seem like a serious, doable technology. There may be others. I have thought in the past that a “rocket mass heater builders association”, similar to the masonary stove association, might make them seem more “official”. Another possibility: get a description and build at a suburban home published in a credible periodical. I know Mother Earth News, Taproot, Grit - all of them will pay for well written and photographed articles. Mother earth, in an open search, has a single article about them, an FAQ. Grit has one article, Countryside has none. I don’t know what the readership of these are, but I think people assume that articles that appear there are vetted a bit more than an open forum or random web page.
Just my two sense. And speaking as someone who has yet to see a rocket mass heater heat a home in person.
2 weeks ago