Purely out of curiosity (I've never permanently lived somewhere where woodburning stoves were essential for home heating): is this because people are over-burning wood to compensate for the slow warming-up time, or because the stoves themselves are inefficient, or something else?
The stoves just put off a lot of particulate pollution. Stoves don't completely combust the wood or do so at the wrong temperature which results in much more pollution than burning an equivalent energy amount gas.
In my country outside of the city center (where most homes have district heating or gas), wood burning stoves are the most common way people heat their homes. Coal never really caught on here, but there are abundant forests and not that many people, so there is always plenty of firewood that is easy to find.
That combined with low temperatures during winter (somehow it causes pollution to stay low to the ground?) means the government usually issue air quality warnings to stay inside a few times during the heating season.
There have been some attempts to improve the quality of the fuels used, e.g. funding to push upgrading to automatic pellet stoves which burn much cleaner, but most of the issue (which is also the case in the UK) is that older homes are simply poorly insulated and waste a lot of heat. The problem is by 'older homes' I mean anything more than 10 years ago, when the EU started pushing for lower energy use in housing. In the US that means today, for homes built to minimum building codes - which the majority of new housing is.
We are building a new 160m2 home - to modern insulation standards - and even the smallest 5kW wood burning stove would produce too much heat for the house. We probably won't even need to turn on the heating (electric heat pump) until it gets close to 0c outside.
>The drawback of taking a long time to heat up shouldn’t be overlooked either. Anyone who has lived in a stone or brick house could tell you...
But have you ever lived in a home with a tile stove like described in the article? The time it takes to heat up isn't really an issue in my experience. Yes, it takes a bit longer than with radiators but unless you're out on holiday your house wouldn't be completely cold, would it? You get up, it's still warm from the previous night, then you throw some fresh wood in the oven and start a new fire. Especially with well insulated homes as they're built these days it works well. But here's the actual problem, apart from taking up space like you already mentioned: The fire has to be maintained. I'm pretty sure that's the main reason they've fallen out of use. It just doesn't fit into our fast paced lifestyle with small families and busy parents anymore. Back in the day there generally used to be someone home, either the housewife or the greatparents or one of the 15 children or so. Wood fired stoves just got automated out of existence like most other stuff. Central heating can be set to a certain temperature and be forgotten about. Sure, you can do that now by getting a modern gas burning tile stove, or retrofitting an old one with modern tech. But by now most have already fallen in disuse. I find it unlikely they will be revived outside of niche cases for the simple reason that fossil fuel is on it's way out. Floor heating is great and can be electric, powered by green energy.
I live in the North where -40 is common. I would say the vast majority of people have a wood stove, and they work exceedingly well.
You might not be aware but ones that burn the wood twice (even three times) are now common and in fact are law in many places. So they're MUCH more efficient, and drastically reduce the particulates coming out the stove pipe.
Another benefit is they only need to be fed once every 24-48 hours (depending on what heat you set the thermostat, what size stove you have, how well insulated your house is and what temperature it is outside.)
My stove is a dumb as it gets. It burns wood and produces heat. More wood and/or more air -> more heat. Living in the countryside has its advantages, I guess it will be hard to cook on a wood-burning stove when you live in a city or suburban environment - not to mention the problem of getting wood to feed the thing, even though it is really quite effective - the equivalent of about 1 m of 2x4 of wood is enough for a 2-course meal for 4 people (not that I feed it 2x4's of course). As an added benefit it heats up the kitchen sufficiently to be used as the only source of heat in spring and early fall here in the Swedish countryside.
Here in the Netherlands I'm starting to smell and hear about lots of people warming their houses by burning wood since the natural gas prices have skyrocketed. Personally I'm not too fond of the idea of breathing in more fine particulate. But trying to ban wood fire heating would be political suicide.
I find the idea that log stoves are part of the problem interesting. Here in America wood burning stoves have pretty strict emissions requirements, to the point where a portion of wood burning stoves sold today actually have a catalytic converters in them to ensure complete combustion of any particulate!
Does the U.K. not have similar rules, or are all of these just grandfathered in?
Outdoor wood furnaces (boilers) became very popular over the last 15 years. They are cheaper than fuel oil. A traditional wood stove has to be refilled every 2 hours (or so), and is also a major fire hazard. "Wood burners" may also include pellet stoves which are also increasingly popular for similar reasons.
Other poster covered it well, but one thing to add. There are the kinds of wood burning stove. Old simple, pre EPA mandated high efficiency stove, efficient stoves with a catalyst to provide the clean burn, and efficient stoves that use secondary air injection to provide a clean burn. The new efficient stoves are a bit more forgiving for throttling them down for long burns without producing too much creosote they can cause chimney fires.
I just replaced the old stove in my house with a new catalyst model and I burn 30% less wood while providing more steady even heat. I am heating 4000 sqft 2 story with only wood heat, one load every 12 hours, house between 80 and 64 degrees depending on location.
Do you have numbers on people in the northeastern US using coal stoves for heating? I'm not necessarily doubting you, but I lived in New Hampshire for a long time and still go back regularly to see family and friends, and I don't think I've ever seen a coal stove. IME most houses use either natural gas or wood pellet stoves for heating. Which aren't ideal but they're leaps and bounds better than coal.
* people have wood anyway so they might as well use it for something
* it often suits the design of houses here which were historically built for a central stove burner like this
* many people have wood-burning stoves for cooking that are extremely large and heavy permanent fixtures in their kitchen and cannot easily be removed or adapted and are designed to permanently be burning wood so you can't really turn them off either
* people like the smell and aesthetic (note this article is in just about the most middle-class publication there is in the UK)
We have the same wood stoves here in neighbouring Romania. Whenever I go visit my parents in the countryside and they heat up the stove I realise how cool of a "technology" it is, that is to still have a heat source many hours after the fire the had done its thing.
Unfortunately building/making wood stoves is a dying art, you can find less and less people who are good at it. And the trouble is that if you build a defective wood stove you risk all sorts of nasty stuff, like dying from carbon monoxide intoxication.
My mum grew up in one of those old farm houses that were heated by open fires. It was always freezing cold in the winter in most of the house. The whole place was later fitted with oil fired heating. My grandmother could never understand why we wanted to build a fire when we visited. The people installing wood burners are a new generation that grew up in centrally heated homes and see it as romantic.
Manually operated wood furnaces are also terrible with regards to particle emissions. The article acknowledges that and claims that oven stoves do not have this problem because they can reach higher temperatures. But that ignores the fact that there is a time period until the fire has reached the right temperature during which the particle emissions are very high (particle emissions from wood furnaces are scary high and dwarf emissions from cars). If the whole neighborhood is heated by these things, then you have several hours of the day with smoke and particles, even if everyone operates their ovens correctly so they reach the correct temperatures for a clean burn.
Furthermore, heat pumps are just so much more efficient, as they actually move several times the amount of energy as heat as they consume as electricity. Combined with floor heating - which gives a much larger surface area for heat dissipation than these oven stoves can ever give you - you can further lower the temperature of the water, raising efficiency even more. Floor heating is also way more comfortable as it gives an even distribution of heat throughout the house, and you don't get cold feet.
> wood heat, which is terrible for outdoor air pollution
FYI, newer wood stoves have a catalytic combustor and burn the gasses as they leave the wood box 2 or even three times. They are much, much more efficient and drastically less polluting (because all the particulates are burned instead of going out in the air)
They're law for all new installs in many, many places.
I grew up in a house that used wood as its primary means of heat (and two smoking parents but they smoked outside exclusively).
These days I live in a house primarily heated by a heat pump (in a region where it does get below 0F on a normal winter), but it has a wood stove.
I can't imagine a woodstove setup that doesn't leak some level of particulate to the inside. No matter what, you can tell there's wood burning inside. It is a pleasant smell (burning white/red oak), but probably not good for health.
So even though I grew up with a wood stove burning all winter every winter and have one now, I seriously appreciate the heat pump as a clean and efficient means of heat for 90% of the season.
To me, wood is a great emergency form of heat as we have plenty of deadfall where we live. But I would bot recommend it otherwise.
And don't get me started on firewood processing...
Wood stoves are charcoal breeder reactors powered by their own vaporized wood gas. The re-radiated heat from the ironwork is what gives them their extreme warmth. They are like many other fuel burners — stage one vaporizes the fuel and stage two burns the vapor — it’s just that both stages are in the same iron firebox.
When you start a fire you want to quickly get the stove up to temperature. Use small split logs and kindling sticks along with some kind of “candle” that burns long enough to get the flames going. Commercial fire lighters (kerosine wax bricks) or even just a bit of kitchen towel with a tablespoon of vegetable oil will do.
The kindling and your first log will burn hot and bright with an attractive yellow flame — like a campfire. At the end of this first burn you will build up a layer of red hot wood embers in the base of the firebox and the ironwork will be about half way to temperature.
The next stage and each stage after that is to put on a much smaller load — often I will just use a single large log — and leave the air intake or door ajar, temporarily. The hot embers will rapidly get the new log hot and the whole thing will instantly go from glowing red to an inferno in under a minute.
At that point you have achieved a self sustaining reactor. You can leave it running full throttle if you want the pretty yellow flames. It will only last 20 minutes though and all the energy will blast up the chimney.
Much better, and indeed the whole reason for having a wood stove over an open grate, is to now shut off almost all of the airflow to the firebox. Low airflow means the combustion goes right down — you may not even see any flames if you go super low — but it also means the stove isn’t being constantly cooled by a high volume of airflow.
If you balance it just right then the flame front of burning wood gas will sit above the logs and permeate the whole chamber. It looks like a cross between Aurora borealis and a Backdraft (1991) slo-mo sequence — a deep red wraith that flaps around slowly, completely unlike the sooty yellow flames you began with. You get a real feeling for how it’s the gas not the wood that’s burning. (Having a stove with a glass viewing window really opened my eyes to their operation.)
A single 10” log — quarter split from a 20” diameter ash tree and air dried for 18 months to <20% moisture content — will now produce 10kW for an hour or more and stay burning for eight. The fire will “keep” overnight and in the morning you can put on a new log, fire it up with the door ajar, and be back at full capacity in minutes.
What’s interesting is that if you run the stove in pretty mode — like a cartoon open fireplace with crackling and burning and yellow flames with the vents or even the whole front door open — you’ll notice that parts of the stove might not even get hot. The iron air intake grill on mine will remain at room temperature because although the flames are vigorous, the airflow is so fast it keeps the stove body cool.
Conversely, once the stove has been running for an hour in slow burn mode, the entire body is practically glowing and requires thick gloves to handle. It is wonderful.
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