Ban on Sale of Coal / Wet Wood

[Jeremy Harris]

Given that only very few trees ever fall across roads or railways, I doubt it's significant when compared to the number of trees felled for firewood, TBH.  Just pulling a fallen tree clear of a road or railway and letting it decay would usually be an option, anyway.

 

The town in that BMJ article, Launceston, Tasmania, only has a population of 67,000, which is slightly less than that of Inverness.  These two photos from that article illustrate the problem faced by even fairly small settlements when some people decide it's OK to burn wood in their homes:

 

This is exactly what happens in our village on a still night in winter; the valley just fills up with acrid smog.  Out of the ~200 houses in our village, there are only a handful that burn wood now, yet that handful of houses can very easily pollute the air that's breathed in by ~500 other residents, by filling the valley with smoke and smog.

 

The other issue with burning wood in homes is that in the open countryside it probably won't be the household burning the stuff that suffer ill effects on their health, it will be those downwind who have no choice but to breathe in the pollutants.

 

 

 

[Ralph]

Just now, Jeremy Harris said:

when some people decide it's OK to burn wood in their homes:

 

In the same way people have done since before they were homo sapiens. That's not to deny the issues you've outlined or that we need to change.

[Jeremy Harris]

17 minutes ago, Ralph said:

 

In the same way people have done since before they were homo sapiens. That's not to deny the issues you've outlined or that we need to change.

 

 

In the past people used arsenic in medicines and rubbed it on their skin to "enhance their complexion", used mercury in the manufacture of hats and as a medicine, and we even believed that smoking was good for health until about 50 or 60 years ago, just as we thought it was OK to use the naturally occurring mineral asbestos for a wide range of purposes.   Just because something seems "natural", doesn't necessarily mean that it's safe.

[Ralph]

Just now, Jeremy Harris said:

In the past people used arsenic in medicines and rubbed it on their skin to "enhance their complexion", used mercury in the manufacture of hats and as a medicine, and we even believed that smoking was good for health until about 50 or 60 years ago, just as we thought it was OK to use the naturally occurring mineral asbestos for a wide range of purposes.   Just because something seems "natural", doesn't necessarily mean that it's safe.

Absolutely but there are a lot of behaviours that are probably not safe or even desirable that we all still do. I wonder if sitting in front of a burning fire connects with something in our brain that other risky things you've mentioned do not? I realise I'm stretching this a bit but vegans make a slightly similar argument about eating meat or dairy. It's not necessary, possibly not good for the individual (i don't actually buy that argument) or the world as whole. 

[Onoff]

So waste motor oil and MDF is still OK to burn?

 

?

[Jeremy Harris]

18 minutes ago, Ralph said:

Absolutely but there are a lot of behaviours that are probably not safe or even desirable that we all still do. I wonder if sitting in front of a burning fire connects with something in our brain that other risky things you've mentioned do not? I realise I'm stretching this a bit but vegans make a slightly similar argument about eating meat or dairy. It's not necessary, possibly not good for the individual (i don't actually buy that argument) or the world as whole. 

 

My primary concern is that the impact of wood burning stoves is on people who have no choice as to whether they breathe that polluted air or not.  In our case, a handful of homes with wood burning stoves are polluting the air for ~ 500 people, and that seems to me to be unreasonable.  The BMJ published an article back in 2015 that showed that domestic wood burning was the single largest source of PM2.5s in the UK, 2.4 times greater than that from vehicle exhausts: https://www.bmj.com/content/350/bmj.h2757/rr-1

 

This is an excerpt from that BMJ article:

 

Quote

The disproportionate amount of PM2.5 pollution from domestic wood burning continues to escape attention. Few people who install wood stoves are likely to understand that a single log-burning stove permitted in smokeless zones emits more PM2.5 per year than 1,000 petrol cars and has estimated health costs in urban areas of thousands of pounds per year.[6]

 

The cited reference [6] is this:

Quote

6. AAQG. Health experts advise that current wood heater models are too polluting to be allowed. Australian Air Quality Group. Available at: http://woodsmoke.3sc.net/health. 2015.

 

 

Those that smoke primarily impact their own health, and those very close to them (and I can choose to not be near a person smoking).  People who choose a particular diet are similarly only affecting their own health.  I have no problem at all with people choosing to do things that only endanger their own health; we should all be free to do as we wish if it doesn't harm others.

 

 

[Onoff]

 

5 hours ago, pocster said:

True . Best build a shelter underground ....

 

Most convert old water tanks not build them from scratch.

 

6 hours ago, pocster said:

Bum !

I’ve just literally broken out my hole in slab and roof for flue - for wood burner .

?

 

Be quicker to fill that way. 

[Onoff]

9 hours ago, MikeSharp01 said:

Challenging for steam buffs like me who like to move the logs down to the house by train - what will I do with all my spare time?

 

You look chuffed.

[Thedreamer]

2 hours ago, Jeremy Harris said:

Given that only very few trees ever fall across roads or railways, I doubt it's significant when compared to the number of trees felled for firewood, TBH.  Just pulling a fallen tree clear of a road or railway and letting it decay would usually be an option, anyway.

 

The town in that BMJ article, Launceston, Tasmania, only has a population of 67,000, which is slightly less than that of Inverness.  These two photos from that article illustrate the problem faced by even fairly small settlements when some people decide it's OK to burn wood in their homes:

 

This is exactly what happens in our village on a still night in winter; the valley just fills up with acrid smog.  Out of the ~200 houses in our village, there are only a handful that burn wood now, yet that handful of houses can very easily pollute the air that's breathed in by ~500 other residents, by filling the valley with smoke and smog.

 

The other issue with burning wood in homes is that in the open countryside it probably won't be the household burning the stuff that suffer ill effects on their health, it will be those downwind who have no choice but to breathe in the pollutants.

 

 

 

 

This is a valley and we are not in this situation. We live very close to the coast the prevailing wind blowing the smoke would mean that it would not reach another house for 30kms+, across the sea. Even then very sparely populated areas. 

 

 

We are in an unusual situation and that's my point, some wood burning stoves are acceptable, like ours, as nobody (with the exception of us!) will ever be affected by the smoke.

 

If I was building an airtight house with MHVR I would not build in a valley as you have no control over the air (except using really good filters). I agree that this is unfair as smog is horrible even in Portree (which is in a valley) and if I had MVHR I would be just as annoyed as you. But what could I do.

 

I incorporated a stove in the centre and focal point of the house design because it worked with our surroundings i.e. free access to sustainable wood and no ill affects on others.

 

 

 

 

Edited February 21, 2020 by Thedreamer

[Big Jimbo]

1 hour ago, Onoff said:

So waste motor oil and MDF is still OK to burn?

 

?

The motor oil, helps to get the MDF started. It's a bugger to try and light on it's own.

[ProDave]

I am another that thinks a wood burner in the sparsely populated Highlands makes sense.  We are in a shallow valley that pretty much faces the prevailing wind so there is almost always air flowing up the valley, and the population density downwind of us is very low.

 

But on the few occasions there is no wind, I don't light the stove to avoid filling the valley with smoke.

 

All we burn is either from our own land as part of an ongoing gradual thinning of the trees, or local windfall collected from close to the house. I don't ever buy wood and can't imagine ever doing so.

[Jeremy Harris]

28 minutes ago, Thedreamer said:

I incorporated a stove in the centre and focal point of the house design because it worked with our surroundings i.e. free access to sustainable wood and no ill affects on others.

 

 

The issue of "sustainable wood" for a wood burning stove is worth exploring a bit.  A mature tree gains dry mass faster than a young tree, around 100kg/year.   Very roughly, a wood stove rated at 6 kW will burn around 2kg of logs per hour, so will consume one mature tree's worth of annual growth every 50 hours of use.  If a wood stove is used for 20 hours per week, from mid-October to mid-March, then that one stove would be burning the equivalent to the annual growth of about 8 trees in a five month period, or 8 years growth for a single mature tree in five months.

 

Assuming that an average tree has a mass of ~3 tonnes when felled at the end of a 70 year life, then to provide a single wood burning stove with fuel needs roughly one 70 year old tree to be felled every 3.75 years.  If a woodland has a full range of trees, from saplings to mature trees, then we probably need a woodland with between 18 and 20 trees to fuel a single wood burning stove sustainably.

 

I would suggest that for the majority of the population of the UK, this could not be considered sustainable.

 

Data sources include this DECC report from 2016 that looked at wood fuel use for domestic heating and hot water across the UK: https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/517572/Summary_results_of_the_domestic_wood_use_survey_.pdf plus some data from Engineering Toolbox: https://www.engineeringtoolbox.com/wood-biomass-combustion-heat-d_440.html

[Onoff]

I fancy making a wood gas generator...

[ProDave]

29 minutes ago, Jeremy Harris said:

 

The issue of "sustainable wood" for a wood burning stove is worth exploring a bit.  A mature tree gains dry mass faster than a young tree, around 100kg/year.   Very roughly, a wood stove rated at 6 kW will burn around 2kg of logs per hour, so will consume one mature tree's worth of annual growth every 50 hours of use.  If a wood stove is used for 20 hours per week, from mid-October to mid-March, then that one stove would be burning the equivalent to the annual growth of about 8 trees in a five month period, or 8 years growth for a single mature tree in five months.

 

Assuming that an average tree has a mass of ~3 tonnes when felled at the end of a 70 year life, then to provide a single wood burning stove with fuel needs roughly one 70 year old tree to be felled every 3.75 years.  If a woodland has a full range of trees, from saplings to mature trees, then we probably need a woodland with between 18 and 20 trees to fuel a single wood burning stove sustainably.

 

I would suggest that for the majority of the population of the UK, this could not be considered sustainable.

 

Data sources include this DECC report from 2016 that looked at wood fuel use for domestic heating and hot water across the UK: https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/517572/Summary_results_of_the_domestic_wood_use_survey_.pdf plus some data from Engineering Toolbox: https://www.engineeringtoolbox.com/wood-biomass-combustion-heat-d_440.html

Interesting analysis.  We have about 8 trees in total * but we don't burn the stove anything like as much as your example suggests.  So just from our modest number of trees, we are probably sustainable for the amount we use the stove, which is not enough for all our heating needs.  We top up with locally sourced wind fall as opportunities present themselves.  Surprisingly this years storms have resulted in very little windfall near here.

 

* it's very hard to count how many trees we have, because probably due to the land previously not being managed for 40 years, the trees that were there grew in clumps.  Our largest tree must have 10 or more "trunks" growing up from one cluster. I am not sure how many tress to count that as.  But most grow in clumps with multiple trunks.

[Jeremy Harris]

4 minutes ago, ProDave said:

Interesting analysis.  We have about 8 trees in total * but we don't burn the stove anything like as much as your example suggests.  So just from our modest number of trees, we are probably sustainable for the amount we use the stove, which is not enough for all our heating needs.  We top pu with locally sourced wind fall as opportunities present themselves.  Surprisingly this years storms have resulted in very little windfall near here.

 

* it's very hard to count how many trees we have, because probably due to the land previously not being managed for 40 years, the trees that were there grew in clumps.  Our largest tree must have 10 or more "trunks" growing up from one cluster. I am not sure how many tress to count that as.  But most grow in clumps with multiple trunks.

 

 

I was going on the data from the DECC study, that suggested an average of about 20 hours use per week for a 6 kW wood burner as being reasonable:

 

 

  My guess is that much of your heating comes from the ASHP and UFH, and that your wood burner is used as a supplementary heat source.  Your house also has a pretty low heating requirement when compared to the average across the UK, I suspect.

[K78]

I am/was planning to install a wood Burner as a winter back up for a ASHP if I go that route. 
 

I had no idea that the damage to health was potentially so high. I admit I’m far from a “green type” and think most of the stuff I read are excuses for stealth taxes. I drive a truck, I’m buying a GTR and I think any green efforts we make as a country make no difference on a global scale.

 

However, burning something that has a direct negative effect on the health of communities downwind is not something I’m comfortable with. 

[ProDave]

Yes most of our heat comes from the ASHP. That keeps the house at 20 degrees but never any more.  We light the WBS when we want to indulge in higher temperatures, like on a day like today wet grey and windy, one sometimes feels the need to overheat. Currently 23 degrees just about everywhere downstairs.  That of course means the ASHP won't kick in for heating for some time.

 

The other time we light it is when very cold and it starts to get a bit cool  upstairs, and a warm downstairs gives more convection heat up the stairwell to warm the bedrooms a little,

 

We don't use the stove for anything like 20 hours a week.  Probably more like once a week for about 4 hours. 

[joe90]

My stove usage is very much like @ProDave (now he’s out of his caravan ?). I supply my stove like Dave with trees on my land and occasional “gifts” (fallen trees on neighbouring land).

[Thedreamer]

2 hours ago, Jeremy Harris said:

 

The issue of "sustainable wood" for a wood burning stove is worth exploring a bit.  A mature tree gains dry mass faster than a young tree, around 100kg/year.   Very roughly, a wood stove rated at 6 kW will burn around 2kg of logs per hour, so will consume one mature tree's worth of annual growth every 50 hours of use.  If a wood stove is used for 20 hours per week, from mid-October to mid-March, then that one stove would be burning the equivalent to the annual growth of about 8 trees in a five month period, or 8 years growth for a single mature tree in five months.

 

Assuming that an average tree has a mass of ~3 tonnes when felled at the end of a 70 year life, then to provide a single wood burning stove with fuel needs roughly one 70 year old tree to be felled every 3.75 years.  If a woodland has a full range of trees, from saplings to mature trees, then we probably need a woodland with between 18 and 20 trees to fuel a single wood burning stove sustainably.

 

I would suggest that for the majority of the population of the UK, this could not be considered sustainable.

 

Data sources include this DECC report from 2016 that looked at wood fuel use for domestic heating and hot water across the UK: https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/517572/Summary_results_of_the_domestic_wood_use_survey_.pdf plus some data from Engineering Toolbox: https://www.engineeringtoolbox.com/wood-biomass-combustion-heat-d_440.html

 

Very interesting numbers. Yes definitely not sustainable for the vast majority of the population but we have enough trees and land for it to work.

 

Our stove is a bit smaller than that at 4.8kw rated output and I would expect our house will be better insulated than the houses in the data. 

 

The stove is also in the middle of the house so the heat is not lost in a gable wall etc. 

 

A number of trees were felled when the access was formed. We should have wood for around seven years. This wood is so well seasoned it's grey. 

 

The trees felled were mostly thirty year old sitka spruce and have been replaced with slower growing native types, in particular oak. I am interested in planting some willow in a rough area of grazing and seeing how much we can produce here.

 

 

 

 

 

 

[Delicatedave]

14 hours ago, Ferdinand said:

This is an interesting proposal.

 

The announcement is that coal will be banned for sale from Feb 2021, and unseasoned wood (moisture <20%) in packages smaller than 2 cubic m (*) from Jan 2024.

 

So it will be anthracite or similar, dry wood, or have space to store it whilst it dries (challenge for posh inner London eg Fulham perhaps). Graphic below is a bit simplified (different emissions from different coal types).

 

There is a Beeboid piece on it here: https://www.bbc.co.uk/news/uk-51581817.

 

It was announced by the Ag & Fish Minister.

 

I am assuming this is devolved, so this would be England only. Sounds like a not bad idea - I think, though some dwellings may need upgrading. 

 

What a difference to the arguments that used to infuriate my dad as a Council Architect around 1970 when the argument against insulation and gas central heating from some ex-mining Councillors would be "we have infinite coal and many of us get it free for life from the NCB".

 

Ferdinand

(* does anyone have an easy way to do superscripts from a normal laptop keyboard? I am sure it exists)

 

 

 

I could never understand why wood burners were not hit as soon as they became popular.

Mind you will it make any difference when China are still building coal power stations and commissioned 400 not so long ago.

To be honest I think we'll all be dead as species long before we kill the planet with smoke. WW3 can't e far off now and we have the clown in charge around the world to kick that of any time now.

[Jeremy Harris]

China are at least behind a massive move to reduce air pollution, after decades of it getting worse and worse.  There are more electric vehicles in China than in any other country on the planet, which is a start, plus they make more heat pumps than any other country, but they have a very long way to go to get their emissions levels even close to those here.

 

One thing we have studied and found hard evidence for is the detrimental impact of poor air quality on human life, but what doesn't seem to have been looked at closely is the impact it may have on plant and animal life. 

[Cpd]

29 minutes ago, Thedreamer said:

. I am interested in planting some willow in a rough area of grazing and seeing how much we can produce here.

 

Just planted 600 willow and eucalyptus that have been developed for  the biomass market (very quick to grow) they are a coppice crop so regrow when harvested. This is on top of the 2000+ other trees I have planted in my garden, and I am also in a very rural coastal  location where my log burner will not be a problem to others. Even though I use my fire a lot I don’t burn anywhere near the numbers that @Jeremy Harris has put up, like others it’s all just random bits collected from friendly farmers or found washed up on the beach. I have two years of wood on stock but also use  anthracite in the winter to keep the kitchen warm over the day without the need to tend it. Don’t use any heating in the summer...... 

[Thedreamer]

5 minutes ago, Cpd said:

Just planted 600 willow and eucalyptus that have been developed for  the biomass market (very quick to grow) they are a coppice crop so regrow when harvested. This is on top of the 2000+ other trees I have planted in my garden, and I am also in a very rural coastal  location where my log burner will not be a problem to others. Even though I use my fire a lot I don’t burn anywhere near the numbers that @Jeremy Harris has put up, like others it’s all just random bits collected from friendly farmers or found washed up on the beach. I have two years of wood on stock but also use  anthracite in the winter to keep the kitchen warm over the day without the need to tend it. Don’t use any heating in the summer...... 

Interesting, I know that willow are fasting growing, but how long will be until you can start harvesting?

 

Also what sort of soil have you got for the willow, where I was thinking of planting is quite boggy, no good grazing for our sheep.

[Ferdinand]

15 minutes ago, Cpd said:

Just planted 600 willow and eucalyptus that have been developed for  the biomass market (very quick to grow) they are a coppice crop so regrow when harvested. This is on top of the 2000+ other trees I have planted in my garden, and I am also in a very rural coastal  location where my log burner will not be a problem to others. Even though I use my fire a lot I don’t burn anywhere near the numbers that @Jeremy Harris has put up, like others it’s all just random bits collected from friendly farmers or found washed up on the beach. I have two years of wood on stock but also use  anthracite in the winter to keep the kitchen warm over the day without the need to tend it. Don’t use any heating in the summer...... 

 

Out of interest, which type of willow?

My favourite is probably Cricket Bat Willow, which as a tree is unusual and attractive, and straight and fast and ultimately 20m high.

Edited February 21, 2020 by Ferdinand

[Jeremy Harris]

16 minutes ago, Cpd said:

 Even though I use my fire a lot I don’t burn anywhere near the numbers that @Jeremy Harris has put up, like others it’s all just random bits collected from friendly farmers or found washed up on the beach. I have two years of wood on stock but also use  anthracite in the winter to keep the kitchen warm over the day without the need to tend it. Don’t use any heating in the summer...... 

 

Just to be clear, they weren't my figures, but were taken from the quoted references.

 

A reasonable common sense cross-check is to look at the heating energy requirement for a house.  Our house has a pretty low heating requirement, it's under the passive house limit, at about 12 kWh/m²/year.  A typical house in the UK might need 3 or 4 times this much heat energy.  We need around 1,600 kWh/year for winter heating, which if we heated the house using a wood burning stove would need about 533kg of dry logs, or a bit over the annual growth of 5 trees.

 

If that much wood is needed to heat a passive house, then it seems likely that 3 to 4 times as much would be needed to heat a pretty average house.