Efficiency testing

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Great point except EPA offers a cafeteria plan for the automotive industry. Chevy (as an example) can make 10,000 Suburban's that get 8 miles per gallon so long as they make and sell 200,00 Chevy Volts. (again only an example).

But reading the study, we need to remember that the fuel and the MC in the fuel was the greatest contributor to PM2.5. EPA and other are in Portola CA trying to now studying actual in-situ installations due to two of the greatest variabilities:

1) User interface
2) Speciation and MC

What's next, regulating the fuel we burn? (Just like the automotive industry)

BKVP
UK has regulations on firewood sales now don’t they? Does Fairbanks too?
 
UK has regulations on firewood sales now don’t they? Does Fairbanks too?
On moisture content?

We could fix a lot with a little educational campaign. Ignorance is the primary enemy, based on watching the first postings of new members to this forum, over the last dozen years. People are routinely surprised that their wood is not dry, or the importance of having dry wood. Even once convinced of that, they measure on the outside face of a split that's been sitting out several weeks, not realizing that's going to give a false low reading. Others assume "kiln dried" means dry, not understanding that firewood kiln profiles are aimed only at killing bugs, and not actually drying wood.
 
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People are trusting and many wood sellers stretch the truth, some to the extreme. Technically one could say that wood split a month ago is seasoned, just don't ask for how long. A common theme is to say the wood is 2 yr. seasoned when it was cut to log length at that time but only split the week before. Ship a moisture meter out with every stove with very clear instructions on how to use it.
 
I know the first year I used my stove I thought split oak would be good to burn after a year. Boy was I wrong.
 
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@BKVP
Sure hope you have someone in the pipeline following/learning the ropes on all this.
Otherwise the next guy/gal will be drinking from a fire hose to get up to speed!
Very kind. After 27 years of "the fire hose", industry has expressed the same concern. But, alas, I'll be at it for at least 1-2 more years. I'm in Munchen (Munich) time for a beer. One of industry catalyst suppliers is headquartered here.

BKVP
 
UK has regulations on firewood sales now don’t they? Does Fairbanks too?
Yes to Fairbanks and also parts of Oregon.

BKVP
 
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We all went thru that!
Yup. At various points in my life when I was working full time I have been shorted, sold green wood as seasoned, sold wood where evidence showed that the bottom of the pile had sat on the ground even though the wood I tested was dry, wood that was supposed to be 16" and was 14-20", etc. Finally, I had a nice 12 yr stretch of processing my own and predictable burning. Now I am back to purchasing wood, but I get it enough in advance to ensure it's dry by November 1.
 
So how exactly is efficiency figured out on these stoves? Do they take the estimated BTU of the fuel load and somehow guesstimate how much of the BTU’s stays in the room compared to how much goes up the chimney? I know they have to monitor chimney and stove temps and that has something to do with it but how can you figure heat transfer efficiency when there’s so many variables?
 
So how exactly is efficiency figured out on these stoves? Do they take the estimated BTU of the fuel load and somehow guesstimate how much of the BTU’s stays in the room compared to how much goes up the chimney? I know they have to monitor chimney and stove temps and that has something to do with it but how can you figure heat transfer efficiency when there’s so many variables?

Here's a test calculation sheet.


It's the "stack loss method". If you have a known fuel, of known moisture content, you can calculate combustion efficiency and heat transfer efficiency by measuring 6 things: weight of the fuel load, room temperature, Flue gas; temperature, CO concentration, CO2 Concentration, and O2 Concentration.

Really you're not actually measuring how much heat the stove releases to the room, instead you calculate how much heat the wood produces (known fuel, moisture content, and weight consumed (flue gas composition ties in here to calculate combustion efficiency)), and how much heat leaves through the flue, temperature and flue gas concentrations.
 
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Here's a test calculation sheet.


It's the "stack loss method". If you have a known fuel, of known moisture content, you can calculate combustion efficiency and heat transfer efficiency by measuring 6 things: weight of the fuel load, room temperature, Flue gas; temperature, CO concentration, CO2 Concentration, and O2 Concentration.

Really you're not actually measuring how much heat the stove releases to the room, instead you calculate how much heat the wood produces (known fuel, moisture content, and weight consumed (flue gas composition ties in here to calculate combustion efficiency)), and how much heat leaves through the flue, temperature and flue gas concentrations.
Here is the full method. It comes from the CSA B415.1.10 Enjoy a little light-reading.

BKVP
 

Attachments

  • CSA B415.1 2021.pdf
    1.6 MB · Views: 72
Went pheasant hunting at 28F for 6 hours. Need to see some high Btu's and get warm fast! Lot's of flame!


BKVP