Dangerous idea, but what do you think?

Lots of greenhouse operators pump extra carbon dioxide into their buildings to boost plant respiration and growth. A clean-burning RMH puts out mostly CO2 and water as exhaust. Now, in my glasshouse at least, the last thing I really want in the "indoor" atmosphere is more water since it's already humid. But wouldn't it be cool to goose it up to 1000 ppm CO2?

I can think of several ways this could go badly wrong. But hear me out...if there was a condenser at the flue outlet to dry the gases, you'd basically be fertilising the plants every time you ran the heater. Maybe have a barometric damper on the stack that redirects once the system is up to clean operating temperature, and obviously some good ventilation options for the structure as a whole, including a purge feature.

I was reading something about this a while ago.
IT SEEMED TO WORK, LOOK IT UP PERHAPS.

Depends on the plants. I believe that tomatoes go bananas (ha) in an enhanced CO2 environment. Other plants do nothing extra.

And yes, dangerous. Better have rock-solid procedures for access, drip feed/irrigation, and really good locks. If the neighbourhood kid wanders in to steal cherry tomatoes, you're in prison, and sued out of existence.

At least if the ruffians broke in to get around the locks, they'd have a fresh air supply....

would the extra humidity be that big a deal???
if you can reduce the humidity from within your existing system it would be easier than trying to remove it from the RMH

The danger is too much CO2.  If it reaches 1% to 2% it can kill you.  Since air is basically 1/5 oxygen that means if you burn over 1/20 of the oxygen in the building you can render it toxic.  This is not CO but actual CO2 levels.  The danger is it controls your respiration rate and if it gets too high basically your body goes on overload and forgets to breath.  Unlike CO which blocks your bodies ability to carry oxygen the CO2 simply when it gets too high can simply cause the body to forget to breath.

If you decide to do it, you have to get several CO and CO2 meters, some of those should have a redundant power source.

EDIT: Also you probably want to run the RMS during night/cloudy weather...this is when plants usually don't need munch CO2 anyway.

A compost heap in the greenhouse is a munch safer and proven solution.

I have another take, in the form of a question: If we artificially accelerate the growth of these plants, are we necessarily doing ourselves any favours from a nutrient density standpoint?

Taking the example of PNW yew in bowyery, the yew that is best for bows grows slowly, in the shaded understory of foothills, as I understand it. If you try to use coddled yew, grown with plenty of everything it needs, the grain isn't as dense as it needs to be.

It might be a slightly different phenomenon than what we see with growing food in inert or depleted media (lifeless soil, most hydroponics and sterile media growing), but if the plants are growing so fast that other processes responsible for their health and nutrient density can't keep up, we might be looking at a similar situation.

So what if, as with the coddled yew growing in one season what would take the shade-grown yew several, the fact that these plants are growing so much more in a single light cycle between rest periods compromises their nutritional value or gene expression?

It has often been speculated that hothouse-grown produce was nutrient deficient simply because the media being used were sterile. But what if there's more to it than that?

But to address the idea, people have burned candles and other fuel-burning appliances to afford CO2 and heat for their greenhouses for centuries, I would imagine. The idea is sound. My opinion on its application, though, is that it's a great solution for CO2 starvation in the greenhouse, but I would stick towards the high-end of normal outdoor C02 levels.

But good luck, please don't suffocate yourself or others, and keep us posted.

-CK

Chris Kott wrote:I have another take, in the form of a question: If we artificially accelerate the growth of these plants, are we necessarily doing ourselves any favours from a nutrient density standpoint?

Taking the example of PNW yew in bowyery, the yew that is best for bows grows slowly, in the shaded understory of foothills, as I understand it. If you try to use coddled yew, grown with plenty of everything it needs, the grain isn't as dense as it needs to be.

It might be a slightly different phenomenon than what we see with growing food in inert or depleted media (lifeless soil, most hydroponics and sterile media growing), but if the plants are growing so fast that other processes responsible for their health and nutrient density can't keep up, we might be looking at a similar situation.

So what if, as with the coddled yew growing in one season what would take the shade-grown yew several, the fact that these plants are growing so much more in a single light cycle between rest periods compromises their nutritional value or gene expression?

It has often been speculated that hothouse-grown produce was nutrient deficient simply because the media being used were sterile. But what if there's more to it than that?

But to address the idea, people have burned candles and other fuel-burning appliances to afford CO2 and heat for their greenhouses for centuries, I would imagine. The idea is sound. My opinion on its application, though, is that it's a great solution for CO2 starvation in the greenhouse, but I would stick towards the high-end of normal outdoor C02 levels.

But good luck, please don't suffocate yourself or others, and keep us posted.

-CK

That is one there are no clear answers on.  Some say it hurts flavor and nutrient density but others say it improves it.  I am going to say the best information comes from the pot growers and the majority there seem to be saying it is a good thing for both yield and flavor provided the plants get enough nutrients and light too.  But since they don't care about nutrient density where does that leave us??

Good point. I was just thinking that CO2 wasn't the only variable that needed to be adjusted.

It might be that to have plants grow properly at an accelerated rate, we'd need to increase not only CO2, but boost soil life population counts, mycelial growth, root-zone oxygenation, and ensure constant supply of sufficient water and nutrients.

It's probable that if food is less-than optimal, nutritionally speaking, it's because there's some type of insufficiency somewhere in the growth cycle. I'm not saying it's insurmountable, just something to keep in mind.

-CK

Timing matters, if I remember correctly.  Some plants need more O2 less CO2 at night, when you would want the heat.

It just happens that I know the guys that run the major grow business on the East Coast. I'll ask what they're doing. This whole line of inquiry came up because I met a couple people who design heat and CO2 enhancement systems for commercial growers and they're interested in biochar. So next I started thinking about RMH applications as well.

Phil Stevens wrote:It just happens that I know the guys that run the major grow business on the East Coast. I'll ask what they're doing. This whole line of inquiry came up because I met a couple people who design heat and CO2 enhancement systems for commercial growers and they're interested in biochar. So next I started thinking about RMH applications as well.

I totally agree with the dream.  I had already been there.  My original plan had been to direct vent the rmh into greenhouse with the biochar system built onto the top of the stove barrel.  After all that would raise the efficiency of the stove to basically 100%  But then I ran into the information on how little CO2 could kill and it scared me off of the thinking for now.  The carbon source needs to be more controlled so I am back to some sort of controlled  gas burner or something like a candle that is smaller and slower.  Or back to compost, mushroom or animal driven systems.

Just a few thoughts to ponder.
If you fire it up about 2 or 3 in the morning it would keep it warm during the coldest part of the night.
If you don't open the door until sometime afternoon they would have that CO2 when the sun comes up and through most of the day when the sun is activating their need for CO2.
You could use grow lights when the heater is burning before sunrise and get more growth, but the lighting would bump up the electric bill.