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Author Topic: Heating with wood or pellets ? and air heat pump ?  (Read 26950 times)

mati

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #50 on: January 09, 2017, 11:53:36 PM »
My Grandfather was a stone mason and built heating walls.
An entire wall of the house was built so that from the central
firehole, the chimney would snake back and forth and heat
up the entire wall.
My mother said, she would build a roaring fire in the morning
and when it had burnt down, the coals would be take out, and
a wooden door put in place to stop the heat escaping.
The wall would heat the room for an entire day.
:)
and so it goes

sidd

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #51 on: January 10, 2017, 07:38:36 AM »
Hypocausts. I have thought about it, but always went for hot water in pex and hydronic heat. Could put it in the walls i suppose, but mediating heat transfer with water seems like a nobrainer, at a heat capacity gain of 800 per unit mass or so.

Next step is to add Glauber's salt tanks to use the phase change storage, but have not got around to it yet. So far used giant insulated tanks of water, but you can drop the volume requirement so dramatically (factor of 70 or so) for equivalent heat storage. I always seemed to have several thousand gallon tanks around when I needed heat storage, so i always went with water. But I could have done the same job with a buncha barrels instead, if i could have been sure of skilled operators to maintain salt concentration.  Unfortunately  that was mostly not the case.

O vell. next time.

sidd

johnm33

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #52 on: January 10, 2017, 02:13:05 PM »
Sounds like a russian stove to me, Ive been contemplating building something between a russian stove and a rocket stove. The idea is to have a permanent chimney fire whilst the fires alight, then to prevent the heat escaping by closing off the air flow once things have warmed up. It's very hard to find out what will serve as the flue for a long enough period, i've thought about using fondue cement, or pozzolanic [crushed fired clay+lime+perlite] or fire clay as the liner or even to make it accessible enough to replace the first 1-1.5M of flue and fitting stainless flue liner or even cast iron to contain the chimney fire section. The advantage of casting a flue would be to create a surface that forces a vortex to form, the advantage of the permanent chimney fire is that 100% of the heat is extracted from the fuel,and the emissions are just co2+h2o.
About 20 years ago there was an inventor living in a former church in Kelso[scots borders] who had mastered the art of containing a rocket stove within a fire, his claims and testemonials were off the scale, plus he claimed zero emissions, his fire kept the whole building warm [it fed about a dozen rads.].

mati

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #53 on: January 10, 2017, 05:00:22 PM »
I found a link to the kind of stove i think my grandfather made, a masonary heater:

http://www.mha-net.org/what-is-a-masonry-heater/


and so it goes

theoldinsane

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #54 on: January 10, 2017, 06:59:07 PM »
Tile stoves were first designed in Sweden in the 18th century in response to a shortage of wood suitable for burning. With a heat-retaining cast iron core and long multi-channel flues, the kakelugns retain heat, keeping rooms warm up to a whole day after the fire is out. Add a cozy touch to your interior with such a stove – it will not only give a comfy touch but also warm you up if you like. Such a stove can fit almost any interior, from a traditional one to ultra-minimalist. Most of tile stoves are white, some of them have patterns but don't hesitate to make a statement with a colorful modern one.

http://resources.made-in-china.com/article/industry-trends/vJgEnlxKBmDY/29-Traditional-Tile-Stoves-in-Home-D-Cor/

John

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #55 on: January 10, 2017, 07:56:46 PM »
I agree with the tile stove concept. One of our neighbors heats his house al day with one load of wood... estimating 30x30x100 cm as a load. He shuts down the non essential rooms and his house has modern insulation so it keeps heat. Here is a link to an example page: http://www.marchesoni.it/it/stufe-su-misura/stufe-maiolica/stufe-a-ole

The interesting thing is that I understand there is no air inlet. He cracks the door to the stove for a few minutes to get it hot and burning well and then closes it. The air, according to him, comes back down the chimney slowly and so the wood burns all day long slowly. I am not going to swear to this part of the story because I am not sure it makes sense to me, but the result seems to.

One nice benefit is that this massive pile of ceramics/stone get warm and it is nice to be able to physically touch the source of heat, as opposed to a metal stove that would burn you.

nicibiene

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #56 on: January 10, 2017, 08:56:23 PM »
I wish we would have prepared for a tiled stove.  :'( The principle is to lead the hot air through channels to catch the heat in the stone masses that are in the rooms-not to leave it through the chimney. It is a pleasant heat coming from that kind of ovens. The principle of floor heating system is the same and you need much less energy to get a comfortable warmth.
“We cannot solve our problems with the same thinking we used when we created them.” –“Learn from yesterday, live for today, hope for tomorrow. The important thing is not to stop questioning.” Albert Einstein

Neven

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #57 on: January 10, 2017, 11:03:13 PM »
We also wanted one, made of loam. But the weight simply couldn't be supported by our floor, and it would have been too costly to have an extra foundation laid for it. It was too expensive anyhow, at least 7000 euros. The project we just finished, cost us 3700 euros, which is still a bit steep, but we decided to pay more for a top quality stove (2000 euros).

I also regret we couldn't install a water-heating stove connected to our 300 liter boiler upstairs, but the stove would've overheated the water (and our polybutylene water pipes can't stand much more than 65 °C), while the air temperature downstairs would still be too low. I'm glad I listened to my plumber and re-calculated my rosy picture.

I then opted for an air-water heat exchanger in the flue right behind the stove, but suspected it wouldn't return on the investment (lots of installation work, creosote cleaning, for just a few kWh worth of water, with the risk of the chimney not getting hot enough). I'm glad I didn't do that either.

All in all, I'm happy. Temps have been really low, it's -13 °C outside as I write this, but it's really comfortable in our living quarters now. Some time soon we're going to try to cook on the stove. If that works well, we're going to save some more kWh in electricity.
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sidd

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #58 on: January 11, 2017, 05:36:47 AM »
Re: water overheat

Yes. For a waterjacket on a wood burner, you always need a place to dump excess heat. Else you risk steam explosion (BLEVE), not nice.

etienne

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #59 on: January 11, 2017, 06:17:32 PM »
Hello,

I got my chimneys cleaned today, and the guy said that the rotative things are not a good idea excepted with very clean fuel (natural gas mainly). They would get dirty and wouldn't turn well after a few years.

I have a drawing problem on one of the chimney and the solution is to change the stove or increase the size of the chimney.

Best regards,

Etienne

in4apenny

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #60 on: January 11, 2017, 06:28:55 PM »

I have a drawing problem on one of the chimney and the solution is to change the stove or increase the size of the chimney.


Is that a chimney flue liner & if so how old is it , if it's getting on a bit then maybe the best option to replace that.

etienne

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #61 on: January 12, 2017, 04:23:24 PM »

Is that a chimney flue liner & if so how old is it , if it's getting on a bit then maybe the best option to replace that.
The house is only 15 to 18 years old. The guy who cleaned the chimney said that it looked like never used. Material really seems standard, and generally speaking, we didn't have any bad surprises with the house. The two other chimney are ok (for the main wood stove on the ground floor and for the central heating burning heating oil). It really is too short, the stove user's manual requires 8 meters and we only have 5 because the stove is on the first floor.

Thanks,

Etienne

johnm33

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #62 on: March 12, 2017, 10:04:23 PM »
I had a few random thoughts after the above exchange, so hypocausts, every time i've read about an excavation of a 'roman' villa, in the uk they've allways been burnt out, so i wondered if the build up of soot and ensuing 'chimney' fire was the cause. Then what are the chances of nobody discovering the rocket stove effect or perhaps the original design was a rocket stove, or russian/masonry stove type, otherwise would the villa have a very short lifetime? and is anyone using this today, given the popularity of beam and block flooring systems? The only lnk I could find was an expired Spanish one using a tiled stove, similar to those referred to above, but no real details about the service to underfloor.  You'd think there may be some CO issues or condensation problems but nothing beyond the wit of man.

etienne

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #63 on: March 09, 2018, 10:43:15 AM »
Hello everybody,

I'd like to reactivate this topic to get some info from people living in low energy houses and heating with wood or pellets.

My parents heat their Minergie House with solar, electricity and wood. They are very happy with the wood-stove, but last time they came over, I found out that they do the fire in the evening, and let it burn when they go to bed. It totally overheats the living-room, but it's not an issue because they are in the sleeping-room. In the morning, they have a good temperature all over the house.

I told them a few times that they should replace it by a pellets stove, so that they could have the nice temperature whenever they want it, but they are happy with what they have.

When I talked about pellets stove in low energy houses, people always say that the heat pump is so much more efficient that it doesn't make sense. People would agree with a wood stove, but don't invest because of the overheating issue.
So until now, I have not been able to get any feed back about that way of heating a low energy house.

Does anybody has any experience to share ?

Thanks,

Etienne
« Last Edit: March 09, 2018, 10:50:27 AM by etienne »

Sebastian Jones

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #64 on: March 09, 2018, 03:10:25 PM »

Does anybody has any experience to share ?

Thanks,

Etienne


Modern high efficiency wood stoves are much more efficient at extracting heat than the best ones from even a couple of decades ago. Where we are, January temperatures average minus 30. This means that an air source heat pump is marginal at best during the coldest months. We could use one for 9 months a year, reducing wood requirements. With such low wood needs, we could hand haul all our wood from our property, and use a battery powered chain saw to cut it.Currently we heat to a comfortable level with a wood stove, burning logs. A pellet stove adds at least one extra level of complexity (more if you include the supply chain for pellets), so we will never use one. We don't suffer from over heating, so long as we are intelligent about operating the stove. We have no problem keeping the entire house warm down to minus 50. Extended cold snaps do mean having to leave cupboards open so pipes don't freeze...People here work together to solve the problem of houses freezing during extended periods away- we take it in turns to stoke each other's stoves. Nobody uses oil or propane for heat except to accommodate insurance companies which frown on wood heat. Nobody has completely eliminated fossil fuels for electricity generation, given our three months without usable sun. The next generation of batteries will go a long way to resolving this issue, but probably won't completely solve it, but if we can get our gasoline consumption down to 100l/ a year, I'd be satisfied. For now.

Neven

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #65 on: March 09, 2018, 05:19:15 PM »
Etienne, I think you already know my situation, but we have just ended our first entire winter season, heating with a 6 kW (range 3.5-8 kW) wood stove (this one). Our insulation is near passive house level, and the house area is approximately 160 square metres. We use the stove to heat the living quarters downstairs of 85 square metres.

For this winter I calculated that we would need around 700 kg of wood. It turned out to be 736 kg. We light a fire in the morning, 1.8 kg of wood to warm the stove up, and then another 1.8 kg on the embers with reduced air supply. The process lasts between 3 and 5 hours. When it's still not warm enough after that, we add another 1.8 kg. At 6 o'clock, depending on the temperature, we may do another round of 1.8 kg to warm up and then another portion of 1.8 kg to keep the room temperature around 20 °C until we go to bed.

That's a maximum of 5 portions of 1-8 kg per day. Only once did it happen 10 days ago that it was -15 to -20 °C outside, while at the same time cloudy and windy. On that day we burnt up 6 portions.

People would agree with a wood stove, but don't invest because of the overheating issue.

I was also afraid of overheating, but it turns out the stove is just right for us. I had considered a pellet stove, but I was put off by all the electronics inside (I'm already having problems with the heat pump and ventilation system that I can't fix myself). Wood is pretty cheap around here, although pellets aren't that expensive either, I believe. A pellets stove consumes electricity as well, so if there's a black-out, you still can't heat your home.

A wood stove is more of a hassle (we just felled a tree on the edge of our plot that I'm going to have to saw into smaller bits this month), but all in all, we're quite happy with it. We've spent around 150 euros for wood, and the chimney sweep will cost us another 90 euros. Electricity would've cost us around 300 euros, so a 60 euro savings. We need to get that to at least 100 euros savings per year (by buying cheaper wood, instead of briquettes this winter) to recoup our investment in the next 20 years.
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Martin Gisser

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #66 on: March 09, 2018, 07:13:26 PM »
Theoretically I would prefer pellets because they
1) can be made of other stuff than wood, e.g. grass
2) give perfect biochar for carbon sequestration
3) need much less space - "concentrated wood"

But I'm with Neven that you should be able to repair the heating system yourself, and that it should operate autonomously. (Else, by Murphy's law the night will come when you freeze your ass off.)
Plus, Neven's oven is beautiful. Nice big window to see the fire. I wouldn't want to miss the light of the flame and the interaction with it.

(Hiding fire in black boxes is one of the original sins of Homo S Sapiens, according to my humble theory of hominin self-dumbification...)

"Modern" pellet heating systems are behind the time as long as they can't produce biochar. A bad investment in misguided engineering...

I'm actually working at a gravity fed pellet stove that produces biochar and requires only primitive clockwork to operate automatically. Right now I open/close the ember outlet by hand every minute. Except for the iron plate there and the bucket, the whole thing is made of (fire-)clay. Alas, my prototype produces way too much soot.

I bet this pellet feed could also be integrated into Neven's wood oven - if you don't want biochar production.

Iceismylife

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #67 on: March 09, 2018, 07:25:56 PM »
...


 The next generation of batteries will go a long way to resolving this issue, but probably won't completely solve it, but if we can get our gasoline consumption down to 100l/ a year, I'd be satisfied. For now.



Wood gas fuel.

Internal Combustion Engines Are My Life

Martin Gisser

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #68 on: March 09, 2018, 07:39:54 PM »
Wood gas! I love it.
What about making this even smaller and using a micro gas turbine for electricity generation - to make a wood gas hybrid electric car?
http://www.azimuthproject.org/azimuth/show/Experiments+in+biochar#woodgas_hybrid_upgrade_pack_for_electric_vehicles

Iceismylife

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #69 on: March 09, 2018, 07:52:19 PM »
Turbo charged wood burning stove.  There are lots of variations on this theme.  https://www.google.com/search?biw=984&bih=750&tbm=isch&sa=1&ei=CdeiWpfJGqOc0gKJxpKABg&q=charcoal+gas+powered+car&oq=charcoal+gas+powered+car&gs_l=psy-ab.3...8926.17754.0.18265.16.16.0.0.0.0.87.1132.16.16.0....0...1c.1.64.psy-ab..0.6.488...0j0i67k1j0i30k1j0i8i30k1j0i24k1.0.jgFNA2rWRog  Old school stuff.

But for home generation I'd use a large stationary engine. I've got a 5L engine that would make 12 hp. and be silent that I want to build.  It runs at about 150 rpm.

Henry

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #70 on: March 09, 2018, 09:05:29 PM »
We live in New Zealand. The house is well insulated, not to passive house standard. It is built on a concrete slab with reinforced concrete walls inside polystyrene blocks for the ground floor with wood frame for the upper floor.
It is heated with water pipes in slab (?hydronic system). There are radiators upstairs in the 3 bedrooms,  and small pipes in a tiled floor in 2 bathrooms upstairs. The heating water is heated by a pellet boiler in the garage. It has a thermostat control that we leave on, set at 19 degrees last winter. We turn the radiators on in morning with an electronic timer, for 2-3 hours and the bathroom pipes come on simultaneously (lovely for the shower!)
We use somewhere between 800 and 1500 kg of pellets- delivered in irritating plastic bags (20kg) that we fill a 100kg hopper with. When cold it may use 2 bags in a day. Usually ~1. Night time temperature in July is -3 - 5 degrees perhaps. We use it for maybe 5 months in the year. 1000 kg of pellets costs $650NZ or $US400??.
The hot water can be heated from the boiler but it’s easier to leave our electric heater on. There is a solar water heater on roof - highly effective in summer. We have a 4kw solar power system, largely supplying the grid as we are disorganized. We use about 5000kwhrs  of electricity annually (‘low user’ for our billing system.
When Tesla find an installer we will have 1 powerwall battery. We have a Leaf car. Useless range but lovely in town. I have placed a deposit for a Tesla 3!! Due possibly in 2020.
Our solar system cost about $NZ16000, and has a very long payback time. The Tesla battery is $NZ11000 here.  The Leaf (Australian model with Australian maps!) cost $NZ40000 new 2 years ago. We do about 8000 km/ yr.
I was driven in a Hyundai EV. Very nice. Much better range. Beautiful car to drive. $NZ55000 here. Very limited numbers of the EV available.
Our electricity system mostly hydro. Some wind. About 25% from gas I think.
If We build another house we would improve insulation. Shrink house. Use more wood, with stone for the heat retaining mass. Heat with heat pump - probably air rather than ground. Via an appropriate architect!
Hope that isn’t too long and answer Étienne

Neven

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #71 on: March 09, 2018, 09:40:51 PM »
(Hiding fire in black boxes is one of the original sins of Homo S Sapiens, according to my humble theory of hominin self-dumbification...)

Yes, Prometheus started it all. And then the grains found a way to become our masters. ;-)

[/quote]I'm actually working at a gravity fed pellet stove that produces biochar and requires only primitive clockwork to operate automatically. Right now I open/close the ember outlet by hand every minute. Except for the iron plate there and the bucket, the whole thing is made of (fire-)clay. Alas, my prototype produces way too much soot.[/quote]

That sounds interesting. Wood contains about 4.5 kWh/kg. How much of that energy remains in biochar?
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Martin Gisser

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #72 on: March 09, 2018, 10:43:23 PM »
Yes, Prometheus started it all. And then the grains found a way to become our masters. ;-)
No, he didn't bring the iron oven plate and chimney, and f-ing paper to start a fire in a dark box... Our masters are now invisible fires in black boxes, like central heating, internal combustion motors, etc. -- Yet I've met only 1 exceptional European who was a true master of the open camp fire, like some sadhus still are in India. At the open camp fire you can study technological dumbification...



Quote
How much of that energy remains in biochar?
10-20% in optimal biochar according to my humble experimental estimation. -- Barbeque char coal has 60-70% according to literature.

The 10-20% seem to be a waste of energy and efficiency factor to most engineers. But I think this is stupid numerology. (Instead they dream up BECCS machines with underground CO2 sequestration in basalt... Ridiculous! Cf. my theory of technological dumbification :) )


BBQ char is suboptimal bio-char, as the pores are filled with tars and oils (more or less biodegradeable, sucking away surrounding soil nutrients in an uncontrollably slow process of bacterial colonization). But you can get optimal biochar from BBQ char if you throw the glowing rest into water after the BBQ (very messy work).

Pellet biochar is best because the fibers are already broken and ready to quickly take up water and bacteria. Grinding char coal needs more energy, is messy and dangerous (coal dust explosion, black lung) and wastes away grinder edges.

etienne

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #73 on: March 09, 2018, 11:52:56 PM »
For this winter I calculated that we would need around 700 kg of wood. It turned out to be 736 kg. We light a fire in the morning, 1.8 kg of wood to warm the stove up, and then another 1.8 kg on the embers with reduced air supply. The process lasts between 3 and 5 hours. When it's still not warm enough after that, we add another 1.8 kg. At 6 o'clock, depending on the temperature, we may do another round of 1.8 kg to warm up and then another portion of 1.8 kg to keep the room temperature around 20 °C until we go to bed.

Neven's stove is really nice. The small fireplace is a good thing. I have to load mine (8kW) it with about 2,5 kg of wood each time, it makes a big difference in kWh, an my parents have an even bigger one (they use 0.5 m logs), I guess this is the reason for the overheating.

When I'm home, I usually turn off the heating oil heater. When it is very cold, I load the stove  about every two hours, a little bit more in the evening or when the kids do homework, but the days were I'm home alone, I usually just do fire in the morning when everybody stands up, and start the fire again before the kids come back from school for lunch, then back again when they comes back in the afternoon. My wife wants more heat so when she's home, we use more heat (let's be honest, also sometimes from heating oil, anyway, some areas are too far away from the stove when it's cold outside). When temperature goes under 5°C, the heating oil heater doesn't agree to be turned off, so I have to turn of the radiators.
Temperature goes up and down very fast and at a much higher level than Neven describes (up to 22°C when it's very cold, up to 23°C or 24°C right now). This is because we leave all the doors open in order to heat the kitchen as well as upstairs the bathroom and the sleeping rooms because we want to limit the heating oil consumption. Furthermore everybody enjoys the infra-red radiation which means that the stove is sometimes loaded faster than really needed, but it's only hot air and temperature goes down quite fast when the wood is burned. We don't make fire long enough to really heat the walls at a high temperature.
A smaller fireplace would make it possible to enjoy as much the infra red radiation without heating so much the room, but than I would have to turn on the radiators in the sleeping rooms and in the bathroom.
I still didn't found the best way to improve energy efficiency. Some more thinking is needed.

I also tried briquettes (http://www.equiwood.be/) and found that heat was produced more regularely and with a lower intensity than with wood, but the municipality provides local wood at a very good price that is prepared in a back to work project for long time unemployed people, these were too many good arguments to stay with wood. Cost per kWh would have been similar (these briquettes are made of wood sawdust mixed with horse excrements).

Thank you for all the shared experiences.

Etienne

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #74 on: March 16, 2018, 01:52:20 PM »
Hello,
I have another stupid question about wood heating. What do you all do with the ashes ? I usually just throw them in the garden, and try not to do it each time at the same place so that most of the plants get some "food".
Thanks,
Etienne

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #75 on: March 16, 2018, 02:35:32 PM »
I throw the ash out in one of the two fields we have, which lie fallow and we mow only twice a year. Not that we have that much ash, four or five small boxes this winter (the box is under the fireplace).

Ash is good as it contains all kinds of minerals, but it can also contain dioxins and radioactive materials (or so I've read somewhere), so not too much.
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silkman

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #76 on: March 16, 2018, 02:56:37 PM »
Ours gets mixed into the compost bins.

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #77 on: March 16, 2018, 04:00:42 PM »
Hi everyone.
My first post !!!
Wood stoves. I have been using one for over 50 years now and l think they are better than any other
form of heating. We live in south west uk not a cold place like some but can be cool enough.
Our stove takes 50cm logs so is one of the larger types. It has a 16kw hot water jacket inside which
leaves about 8kw to the room. The jackets gravity feed into a hot water tank which when hot enough
a pump switches on which then feed bathroom towel rails then cast iron radiators. We light the stove
in mid September and it runs through until early May.This year I have not had to re-light it at all as we have not been away for more than 36 hours at a time.If you chose a good stove and have a suitable
supply of various woods then it is not a problem at all. I only clean the stainless steel chimney once a
year and remove about 3 mugs of soot. The key is seasoned wood.Over heating or under heating is down to control and type of wood being used. Our supply of wood comes from our own wood.I could rattle on for a week about this so will stop now.

oren

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #78 on: March 16, 2018, 08:10:08 PM »
Welcome, one eye!

etienne

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #79 on: March 16, 2018, 08:27:31 PM »
Ash is good as it contains all kinds of minerals, but it can also contain dioxins and radioactive materials (or so I've read somewhere), so not too much.

One year I found a supplier that had firewood on pallets, we thought that it was a good idea but after delivery, we learned that it was coming from some undefined area on the east of the European Union. The wood was analysed and there was some radioactivity, but nothing to worry about because it was less that what is allowed in babyfood. That year, ashes went into the trash and I make sure I buy local wood.

I also heard that tools would leave some metal on the wood (nickel...) and that it could be a problem when burning wood chips because you transform like 500 to 1000 m3 chips in 1 m3 ashes. This could also be an issue with pellets.

Neven

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #80 on: March 16, 2018, 10:08:01 PM »
I don't want to exaggerate any dangers, but it makes sense that as trees filter pollution out of the air, they get in the wood, and there could very well be some residue in the ashes, which is why I won't use too much of it in the garden (not that I have a lot). I had some very religious friends who burned impregnated pellets (so cheap!) and put all of the ash, lots of it, in their vegetable garden. I don't have Jesus to protect me.  ;)

PS As is most probably the case in Luxembourg as well, the heating season gets prolonged by an extra week. We're hitting -10 °C the night after tomorrow.  >:(
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sidd

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #81 on: March 17, 2018, 05:18:13 AM »
I've made KOH from wood ash for bioD, it's a pain. Compost the thing, great for neutralizing dogshit and catshit, like lime. Also can use it with woodchips in humanure. If you have a lot you can remediate acid soils.

I don't think you need to worry about toxics picked up by trees from the air. Much bigger problem it what they pick up from the ground and the water.

sidd

etienne

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #82 on: March 17, 2018, 05:18:58 PM »
PS As is most probably the case in Luxembourg as well, the heating season gets prolonged by an extra week. We're hitting -10 °C the night after tomorrow.  >:(
Looks like it won't be as terrible as what was first said. Previsions are now around -5°C. Today, the soil was still warm and wett, but the air was very cold, so the water and dirt was freezing on the dogs' fur.

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #83 on: March 17, 2018, 06:53:14 PM »
Yes, the forecast improved here too. Let's hope it's correct. I'm tired of burning wood.  ;)
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Martin Gisser

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #84 on: May 24, 2018, 10:43:22 PM »
Ashes: Here in Barvaria there remain lots of stupid ovens which were constructed for burning coal - and lots of stupid people are still using these ovens for wood (plus paper and garbage for most)  - and then complain about the amount of ashes. I'm just moving into such a place (old abandoned farmhouse).

A well constructed and well-fed wood oven does not produce much ashes and shouldn't even have a fucking ash tray.

I will not re-create the garden around this (actually very beautiful) house because the soil is likely contaminated from a century+ of fucking trash ashes: Mercury from brown coal, lead and cadmium and an overdose of arsenic etc. from painted garbage wood and paper... E.g. yummy stuff like this: https://en.wikipedia.org/wiki/Paris_green combined with lead paint and cadmium yellow/red on Barvarian furniture. What a toxic mess, incl. the mercury soaked oven fireclays, to haul to the waste - while the women are whining over each and every piece... and the elderly neighbor advising to just burn it...

« Last Edit: May 24, 2018, 11:50:24 PM by Martin Gisser »

LeonK

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #85 on: September 19, 2018, 12:58:13 PM »
I think if you are looking for a fireplace for interior purposes you'd better try bioethanol fireplaces https://www.store.planikausa.com/. They have a luxurious and stylish look and are totally safe for the environment.
« Last Edit: September 30, 2018, 11:15:07 AM by LeonK »

etienne

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #86 on: September 19, 2018, 04:58:52 PM »
Why not, they talk about 6kW, so that's fine for most applications. They talk about 82$ for 3 gallons (12 qt), but I didn't find any information about energy (kWh) per gallon. Do you have the information ? I calculated something, but it seems to me too expensive per kWh, so I prefer not to mention it.
Seems a good idea for high insulated houses because you can turn it on and off very easily.

Do they suggest any recycling for the bottles ?

Personnaly, I like the wood I get locally from a back to work project for unemployed people. It is social and cheap, just that I have to wait until it is dry.

Neven

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #87 on: September 19, 2018, 06:35:38 PM »
I think if you are looking for a fireplace for interior purposes you'd better try bioethanol fireplaces. They have luxurious and stylish look. besides they are totally safe for the environment. My wife and I are using Planika ethanol fireplace (https://www.store.planikausa.com/) for years and we are very satisfied!

Make sure oxygen levels in your home don't get too low (buy a CO2 meter, if not too expensive) because the bioethanol fireplaces will quickly burn it up.
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johnm33

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #88 on: September 20, 2018, 12:16:48 AM »
"(buy a CO2 meter, if not too expensive)" and a CO meter without fail.

etienne

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #89 on: October 01, 2018, 08:41:22 PM »
Have you ever heard of a fast floor heating ? I found the picture below very impressive. It is a system where the pipes are in insulated material and directly connected to the flooring.
If somebody is interested : www.opal-systems.be
In this context, tiles have been added. If I'm right, insulation of the building has not been changed.

sidd

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #90 on: October 01, 2018, 09:01:40 PM »
I've put in a couple three hydronic underfloor heating, and the residents absolutely love it. I was worried about difficulty of repair in case of a leak, but they have held up well, one install is more than a decade old and going strong.

sidd

etienne

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #91 on: October 22, 2018, 08:41:01 PM »
I have a crack in the window of my wood stove. It's unbelievable how much it reduces the efficiency.
I used to be very fast at 24°C in the room, and yesterday, it really didn't work (well, I didn't try very hard).
We'll use a little bit more heating oil because I don't trust it now. Repairs shouldn't be an issue, just that shops are closed on Monday.

etienne

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #92 on: November 15, 2018, 09:47:02 AM »
Well, everybody told me that once the window is broken, that the stress is removed and that I can keep using the stove until the new one comes.
Improvements are very impressive, I get an 89% efficiency and a small particle filter on the new one.

By the way, here is a french/german website about heating with wood. Most energy pages from the belgian Wallonie are very good, these ones also.
http://www.lamaitrisedufeu.be/fr/
http://www.richtigerumgangmitfeuer.be/de

Neven

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #93 on: February 12, 2019, 11:15:20 PM »
Remember this problem?

Today I had smoke coming out of my stove, coming into my living room! And it was because there was a huge, cold wind outside (-5 °C) keeping the chimney cold, sucking away the air from the inlet. Man, the flames would just go out, the stove would go completely dark (with a faint glow in the middle), and out came puffs of smoke through the door and the cooking lid. I guess, the stove isn't as airtight as I thought, at least not in these circumstances.

I solved it this winter by installing this chimney addition. The pictures below explain how it works, no moving parts. No problems whatsoever anymore, no matter how hard the wind is blowing or how cold it is. It also made my chimney another 30 cm longer, which is great, because it isn't very long (long enough according to the chimney sweep who tested the pressure).
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oren

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #94 on: February 13, 2019, 01:57:41 AM »
Nice solution.

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #95 on: May 22, 2019, 08:36:36 AM »
Etienne, I think you already know my situation, but we have just ended our first entire winter season, heating with a 6 kW (range 3.5-8 kW) wood stove (this one). Our insulation is near passive house level, and the house area is approximately 160 square metres. We use the stove to heat the living quarters downstairs of 85 square metres.

For this winter I calculated that we would need around 700 kg of wood. It turned out to be 736 kg. We light a fire in the morning, 1.8 kg of wood to warm the stove up, and then another 1.8 kg on the embers with reduced air supply. The process lasts between 3 and 5 hours. When it's still not warm enough after that, we add another 1.8 kg. At 6 o'clock, depending on the temperature, we may do another round of 1.8 kg to warm up and then another portion of 1.8 kg to keep the room temperature around 20 °C until we go to bed.

That's a maximum of 5 portions of 1-8 kg per day. Only once did it happen 10 days ago that it was -15 to -20 °C outside, while at the same time cloudy and windy. On that day we burnt up 6 portions.

People would agree with a wood stove, but don't invest because of the overheating issue.

I was also afraid of overheating, but it turns out the stove is just right for us. I had considered a pellet stove, but I was put off by all the electronics inside (I'm already having problems with the heat pump and ventilation system that I can't fix myself). Wood is pretty cheap around here, although pellets aren't that expensive either, I believe. A pellets stove consumes electricity as well, so if there's a black-out, you still can't heat your home.

A wood stove is more of a hassle (we just felled a tree on the edge of our plot that I'm going to have to saw into smaller bits this month), but all in all, we're quite happy with it. We've spent around 150 euros for wood, and the chimney sweep will cost us another 90 euros. Electricity would've cost us around 300 euros, so a 60 euro savings. We need to get that to at least 100 euros savings per year (by buying cheaper wood, instead of briquettes this winter) to recoup our investment in the next 20 years.

Sorry for interrupting, but let me add my two cents - pellet burners run at stated efficiencies as the pellets are kiln dried then sealed in bags (as far as I know wood burners rarely run at full efficiency as the wood is never dry enough). But that's also a huge disadvantage - pellets MUST be stored dry, if they get even slightly wet take them to the landfill, so you need a quality waterproof shed or garage to store a winters worth. They also need power, so for most people, like a heat pump, if the power goes off so does the heating. The solution - a $100 portable heater for emergency use only, or you could invest in an inverter and battery - another $500 gone.

If you can find one that will work with no electricity, then one might make a good choice. We had a pellet stove, but put in a wood stove instead. Wood is free (well, the labor isn't) on our farmette/area because trees are plentiful and our property has enough to use. Buying logs has been cheaper than buying pellets. A ton of pellets is usually around $220--and you have to pick them up, and stack them in a dry spot. If you run through 4 tons a year, you are pushing $1000 for heating. I haven't spent that much in wood in 4 years.

Checked out chimney addition by Neven again, looks nice.
« Last Edit: May 27, 2019, 04:14:07 AM by JaredK »

etienne

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #96 on: May 26, 2019, 05:13:52 PM »
I have a cousin who made a pellets water heater that doesn't need electricity. He sold the patent to somebody who should supply the north American market. If somebody is interested, I can ask if it is already available. In Europe it doesn't make sense because most people are connected to the grid.

Pmt111500

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #97 on: September 20, 2019, 02:35:59 PM »
As my fitness isn't anymore good to organize (saw and chop, carry) wood for my wood stove I've joined the air heat pump crew. Winters in reversed fridge, why not?

In Finland wood stoves are usually centered in the house, this leads to an uneven temperature in rooms, by the stove it might be 25c even in the -25 temperatures outside, but the near the outer walls the room temp is more like 16-18.

Air heat pumps are (i guess) best used by running them episodically during the day. Planning to warm up the two rooms by timer starting from 5am-7am (normal time to get up) and as needed (2 hours?) on the evenings. The wooden house is a bit airy so some of the warmth goes in to the walls and hopefully also floors. I guess shorter periods of runtime could work for stone/tiled house. No point in keeping the thing running all through days, well, maybe I change my mind at -15c outside.

"Join the climate coolers, use an air heat pump when cold" The cold wind by the rotor of the outside unit is a clear indication heat is moved. The fellow installing it said that I might get by with the machine alone. A bit worried of the ice build up on the AHP later, as this is quite a moist location, two days ago observed first frost on the cars of the house.

(Added an image of the stove, takes c.2m2 plus the space to store the wood)
(Added an image of the internal part of the pump, deliberately installed near the floor to allow better spread of the heated air. I'll have to see how this location works for cooling, but too hot temperatures are yet a minimal nuisance in Finland. Maybe three days last summer were too hot to get sleep before midnight.)
« Last Edit: September 20, 2019, 03:26:17 PM by Pmt111500 »
Cooling the outside by heat pump.

etienne

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #98 on: September 20, 2019, 03:25:56 PM »
My experience with heat pump is that they are the most efficient when they work with the lowest possible temperature, so this means a good insulation and running all the day, not just when some heat is really needed.  Of course if the insulation is weak, than you can't use that strategy.
Heat on demand is something that is easy to achieve with wood. Anyway, when it is very cold outside, an air heat pump is not much more efficient that an electrical heater so it might be interesting to get some wood to do some fire (it could also be briquettes if it easier). During very cold weather, all the spare capacity is used to produce electricity, also from fossil fuels.
« Last Edit: September 20, 2019, 03:43:41 PM by etienne »

Pmt111500

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Re: Heating with wood or pellets ? and air heat pump ?
« Reply #99 on: September 20, 2019, 03:35:54 PM »
My experience with heat pump is that they are the most efficient when they work with the lowest possible temperature, so this means a good insulation and running all the day, not just when some heat is really needed.  Of course if the insulation is weak, than you can't use that strategy.

Yes, I could put the addition of extra insulation on the table on the house meeting, when it's time to renew outside cladding (of planks). They are starting to be rather worn out, my guess they're from the 1950s.(house itself is a rather massive 1920s thing.)

About the wood, I planned to build a storage just for that beside the stove, maybe i'll still do that. I have enough space for storing the wood for mild winters inside but for severe winters I'd need to store some outside, and I'm not going to fall down on stairs with chopped wood again.
« Last Edit: September 20, 2019, 03:44:50 PM by Pmt111500 »
Cooling the outside by heat pump.