3 ms·

Yes, even a metal stove can be efficient…it does not have to be made of stone. The efficiency increase of a proper designed wood stove over a fireplace is due t

Yes, even a metal stove can be efficient…it does not have to be made of stone. The efficiency increase of a proper designed wood stove over a fireplace is due to two factors 1. Metal wood stoves slow the combustion rate down by blocking incoming air. So they can burn logs over several hours rather than all at once. Obviously the stove must be airtight. Russian wood stoves just use a mass of masonry and have lots of internal baffles to extract the most heat. They burn a large fire at a high temperature to have increased efficiency and extract the most heat into the stone. 2. Both types of stove use high temperatures and preheated secondary air to achieve complete combustion. Open fireplaces let 50% of the energy in the wood escape as unburned gases.

Karrot_Kream 5y ago
> Russian wood stoves just use a mass of masonry and have lots of internal baffles to extract the most heat. They burn a large fire at a high temperature to have increased efficiency and extract the most heat into the stone. Yeah these are called Masonry Heaters [1] in the West. They work by forcing the heat generated through combustion to dump as much of its energy as possible into parts of the heater that live inside the house rather than venting hot air out of a chimney. The goal of an efficient masonry heater is to make sure the exhaust gas is cold so that all the heat energy has been extracted. > Both types of stove use high temperatures and preheated secondary air to achieve complete combustion. Open fireplaces let 50% of the energy in the wood escape as unburned gases. The alternative here is to use a catalytic converter to start a secondary reaction and burn exhaust gasses themselves releasing even more heat and resulting in a cleaner burn and fewer harmful exhaust gasses. Modern American wood stoves can come with EPA certifications [2] indicating the use of the catalytic converter or some other technique (say, a secondary burn chamber) to reduce exhaust gasses. [1]: https://en.wikipedia.org/wiki/Masonry_heater https://en.wikipedia.org/wiki/Masonry_heater [2]: https://www.epa.gov/burnwise/epa-certified-wood-stoves https://www.epa.gov/burnwise/epa-certified-wood-stoves
- hasmanean 5y ago
  Yes a catalytic converter would make the stove suitable for widespread use in a city. Though it seems like NASAs solution to the space pen problem…As the old saying goes … “the Russians just used a pencil.” In this case the Russians just used a heck of a lot of bricks. It’s a solution suitable for Siberia…where You don’t want to trust the fate of your winter nights to something with a catalytic converter! Or worse yet, a wood stove with firmware! ( Unless it’s damn simple. )
  - Karrot_Kream 5y ago
    Masonry heaters and catalytic converters/secondary burn chambers are somewhat unrelated. The masonry heater forces the exhaust gas to keep as much of its heat inside the indoors as possible. An efficient stove produces a very efficient reaction to burn its input fuel, creating higher temperatures and cleaner exhaust gasses. The masonry heater is a solution meant for a time when folks didn't know how to cleanly/hotly burn wood. The two methods (efficient wood stove and masonry heating) can be combined for even more heating efficiency. The problem with masonry heaters is that they require the house to be built alongside the masonry heater (e.g. you need to run the thermal mass inside the house so it can convect heat into the house). The thermal mass required can also be very expensive and/or labor intensive to make. Moreover cleaning a masonry heater and maintaining it can be a large pain depending on the size of the thermal mass. Catalytic converters have been in widespread use for automobiles since the '70s (that's ~50 years) so they're pretty proven technology now. Secondary burn chambers are even older (early 1900s I believe.)

Karrot_Kream 5y ago

> Russian wood stoves just use a mass of masonry and have lots of internal baffles to extract the most heat. They burn a large fire at a high temperature to have increased efficiency and extract the most heat into the stone. Yeah these are called Masonry Heaters [1] in the West. They work by forcing the heat generated through combustion to dump as much of its energy as possible into parts of the heater that live inside the house rather than venting hot air out of a chimney. The goal of an efficient masonry heater is to make sure the exhaust gas is cold so that all the heat energy has been extracted. > Both types of stove use high temperatures and preheated secondary air to achieve complete combustion. Open fireplaces let 50% of the energy in the wood escape as unburned gases. The alternative here is to use a catalytic converter to start a secondary reaction and burn exhaust gasses themselves releasing even more heat and resulting in a cleaner burn and fewer harmful exhaust gasses. Modern American wood stoves can come with EPA certifications [2] indicating the use of the catalytic converter or some other technique (say, a secondary burn chamber) to reduce exhaust gasses. [1]: https://en.wikipedia.org/wiki/Masonry_heater https://en.wikipedia.org/wiki/Masonry_heater [2]: https://www.epa.gov/burnwise/epa-certified-wood-stoves https://www.epa.gov/burnwise/epa-certified-wood-stoves

hasmanean 5y ago
Yes a catalytic converter would make the stove suitable for widespread use in a city. Though it seems like NASAs solution to the space pen problem…As the old saying goes … “the Russians just used a pencil.” In this case the Russians just used a heck of a lot of bricks. It’s a solution suitable for Siberia…where You don’t want to trust the fate of your winter nights to something with a catalytic converter! Or worse yet, a wood stove with firmware! ( Unless it’s damn simple. )
- Karrot_Kream 5y ago
  Masonry heaters and catalytic converters/secondary burn chambers are somewhat unrelated. The masonry heater forces the exhaust gas to keep as much of its heat inside the indoors as possible. An efficient stove produces a very efficient reaction to burn its input fuel, creating higher temperatures and cleaner exhaust gasses. The masonry heater is a solution meant for a time when folks didn't know how to cleanly/hotly burn wood. The two methods (efficient wood stove and masonry heating) can be combined for even more heating efficiency. The problem with masonry heaters is that they require the house to be built alongside the masonry heater (e.g. you need to run the thermal mass inside the house so it can convect heat into the house). The thermal mass required can also be very expensive and/or labor intensive to make. Moreover cleaning a masonry heater and maintaining it can be a large pain depending on the size of the thermal mass. Catalytic converters have been in widespread use for automobiles since the '70s (that's ~50 years) so they're pretty proven technology now. Secondary burn chambers are even older (early 1900s I believe.)