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Treacodactyl

Most wood energy schemes are a 'disaster' for climate change

http://www.bbc.co.uk/news/science-environment-39053678

Not at all surprising and worth reading if you're in favour of subsidies and regulation.
tahir

I'm in favour of subsidies and regulation, but I've yet to come across any that are well thought out. My nephew is a commercial lawyer who worked on a thankfully failed biogeneration scheme that would have relied on woodchip from Brazil!
Mistress Rose

The carbon cycle is one that is very difficult to get your head round and the think tank has failed in this too. If you thin a plantation the remaining trees grow faster as they have more room and light, so take in more energy. If you clear fell and replant, then the new trees won't take in as much energy as you burn, but will do over their life time. If you coppice, which is the traditional way of obtaining fuel wood for both charcoal (main fuel for industry) and logs, the new growth from the coppice will take in a lot of carbon quickly and definitely over the lifetime of the coppice.

I agree that shipping from clear cut areas half way around the world is not going to do anything for the carbon sink, nor is the energy needed to chip huge trees. On the other hand, the smaller wood that might be discarded can be used. Another problem with this is the risk of importing pests and diseases, which is something the Forestry Commission are worried about. If you are alternatively bringing coal, oil or gas from a similar distance, there is a marginal increase in energy as the woodchip has slightly less calorific value.

It is a good idea to use waste first rather than woodchip from newly felled trees, but there isn't enough to go round, which is why we import timber/gas/oil into the UK anyway as we can't grow enough for our energy needs. We have a small island and a large population, so we can't be self sufficient in anything including food and energy.
jema

The problem is as just about always, is whether subsidies and regulation are there for the environment or for some lobbyists self interest?
Slim

Clearly it's not a great solution for everyone and everywhere, and clearly accounting needs to be done appropriately.

But some of these ideas are being put forward with a disturbing lack of context.

Though I believe that wood can be used sustainably, and in a manner that is actually carbon neutral, minus cutting and transport emissions, let's go with the idea that new growth isn't taking up 100% of the carbon that harvested wood is emitting when burnt.

What are we comparing that with?
Versus solar power, yup, that's a problem, we're emitting atmospheric carbon where we otherwise only need to do enough to make the panels and components.
Versus literally any fossil fuel? Give me the wood biomass please. That's comparing ancient carbon that would otherwise be stuck under the earth with geologically "recent" carbon that would otherwise be cycling in the forest.

Biomass is fiddling with above ground carbon pools, and needs to be done in a way that doesn't start depleting soil carbon stocks, etc, but anything fossil fueled is dumping ancient carbon into the system where it hasn't been for millions of years with no easy way to get it back out again.

Seriously, which would you prefer?

Also, I'm not saying that Europe should be importing wood chips. What the hell is wrong with you? (not *you* you, but *Europe as a whole* you) Can those economics even work?
Slim

Here's an example of biomass being done well, with a much lower greenhouse gas equivalent than coal or natural gas

https://www.fpl.fs.fed.us/documnts/pdf2015/fpl_2015_gu001.pdf

Some more interesting considerations

http://www.sciencedirect.com/science/article/pii/S0961953415001798


And apologies for what the hell is wrong with you comment previously. Upon further consideration, shipping wood chips around may still be better than shipping coal, oil, etc around! Laughing

Seriously, what is the benchmark that is being compared against?

Is this an example of "it's not perfect, so why do it at all" when the alternative is...... what?
Treacodactyl

The carbon cycle is one that is very difficult to get your head round and the think tank has failed in this too.


I don't think they have. They've pointed out the fact that many simply ignore in that it takes many years for the carbon to be reabsorbed and that's assuming replanted trees will be allowed to regrow and ignoring the carbon used to process and ship the stuff.

We do indeed generate woodchip from more sustainable sources in the UK, arb waste, thinnings, brash from clear fell etc but I gather from those that try and sell the stuff the prices have fallen due to the imported chip.
Mistress Rose

Interesting articles Slim. I read the abstracts for both, but think I will look at the whole thing later. Some parts of Europe do not have the room to grow the trees they need for biomass; Britain, the Netherlands and Belgium being examples. Others, such as France and Germany might, and have a tradition of log burning that we don't. Britain has plenty of coal, and the only way we can be self sufficient in energy is actually to use that.

Treacodactyl, yes they were right to highlight those points, but if woodland is regrown, either by new planting or coppicing, over time, all or most of the gas emitted will be reused. I don't recall any work being done on the rain of twigs, leaves and other odd stuff that comes off trees all the time to see how much a tree sheds and is converted to humus over a year, but I am sure someone somewhere has done the work.

A lot does come down to economics and security of supply. The only way to achieve security of supply and the amount needed is to import, but of course that does cut out the extra processing and the transport by road, which is more expensive, of locally produced material. I would love to be able to sell the brash for energy production, but the small amount we produce wouldn't even be an hours burning for a power station.
Treacodactyl

but if woodland is regrown, either by new planting or coppicing, over time, all or most of the gas emitted will be reused.


It's a big if, and reading the link I posted it seems unlikely it will all be replanted. But that is still missing a big point and that is we need to reduce carbon emissions now not 50+ years when the trees that may have been replanted are at the age when they're absorbing a decent amount of CO2 that's been pumped out by burning their parents.
Slim

but if woodland is regrown, either by new planting or coppicing, over time, all or most of the gas emitted will be reused.

It's a big if, and reading the link I posted it seems unlikely it will all be replanted. But that is still missing a big point and that is we need to reduce carbon emissions now not 50+ years when the trees that may have been replanted are at the age when they're absorbing a decent amount of CO2 that's been pumped out by burning their parents.

Agreed, however, what is the alternative to burning that recent carbon?

There is the most ideal solution, and the least ideal solution, and reality is probably somewhere in the middle.

What should the next power plant be? Which power plant should be the first to be shuttered?

I say, the next power plants should be solar/wind if possible, clean modern nuclear next priority, and that the first ones to be shuttered next are coal, then oil and gas in that order.

biomass may not be perfect, but again, what is the comparison being drawn against?
Mistress Rose

In the past trees were coppiced for fuel in the UK. This can be anything from a 5-7 year cycle for hazel to about 20 year for other trees. This is hardly waiting 50 years for them to regrow. It worked well for centuries and their offspring are still with us, particularly in Dorset, Hampshire, Sussex and Kent. Willow is even shorter cycle, but to keep going indefinitely needs fertiliser, which the others don't.

I realise that not every country has trees that coppice, but certainly in the UK chipping coppice wood is the best option for power. Coppice wood was used to provide charcoal for iron furnaces before the use of coke, was used into my lifetime to power bread ovens local to me (and we are in suburbia) and is making a comeback in that direction.
Treacodactyl

We're not talking about what could possibly be done, we're talking about what is actually being done such as the importation of wood biomass from the US and Canada, much is non-coppicable pine and the broadleaves they are felling don't appear to be managed sensibly but are clear felled forest. Slim

We're not talking about what could possibly be done, we're talking about what is actually being done such as the importation of wood biomass from the US and Canada, much is non-coppicable pine and the broadleaves they are felling don't appear to be managed sensibly but are clear felled forest.

Canadian forestry includes some of the best practices in the world! They have strict rules regarding re-planting.

And yes the discussion of what is being done necessitates discussion of what can possibly be done.

If you stop the current biomass system currently set up, what do you replace it with? If you alter the current system because of these concerns, what do you change?

Right now all that I'm seeing is "I don't like this". Where does that get anybody?
Treacodactyl

Right now all that I'm seeing is "I don't like this". Where does that get anybody?

I could say all I see is people trying to deliberately mislead themselves and others. Wink

I understand you can get biomass from short rotation coppice but that doesn't mean most of the biomass we burn in the UK comes from that. I understand some places manage forestry well but that doesn't mean everywhere does, etc.

I've said many times before I would prefer some of the money that's poured into renewables to go into reducing our demand for energy.
Slim

Quote:
I've said many times before I would prefer some of the money that's poured into renewables to go into reducing our demand for energy.


In this thread?
Regardless, I can get behind that.

Do you agree that the reduced demand would be best used to reduce coal usage?
Treacodactyl

Not in this thread no, I don't think many people are interested in reducing their consumption so I try not to bang on about it.

I'm not sure what should be reduced first, I've seem some claims that some biomass produces 5 times more CO2 than coal, plus other harmful emissions. I've no idea if that is a realistic number but if it is then wouldn't it make sense to reduce that? If fracked gas is really as evil as people say should we not burn more coal than gas?
Slim

I would look into that claim with a strongly critical eye, and again, keep in mind the lifespan of the carbon that's being released.

Do you agree that geologically short term carbon cycling is better than long term cycling? (i.e., it's better to release carbon sequestered 150 years ago than carbon sequestered millions of years ago)

There are issues with fracked gas, but I don't think it's worse than coal for various reasons, primarily among them the amount of prehistoric carbon emitted per watt generated
Treacodactyl

The question appears more like is it worth releasing more CO2 from short term cycling than less from long term. Now I thought there's a point of no return of CO2 levels, are we likely to reach that sooner by burning certain sources of biomass? Slim

The question appears more like is it worth releasing more CO2 from short term cycling than less from long term.

I think this is where our core disagreement comes in.
You've pointed out that biomass schemes are not perfect, and that the assumption that regrowth carbon sequestration will exactly equate to carbon released at burning is flawed.

That does not mean that there is no biomass re-growth and carbon sequestration.
Also it's glossing over the fact that young forests sequester carbon at a faster rate than old forests, and that's not even bringing into the equation the (debated) notion that "stable" old growth forests are carbon neutral, not sequestering any more than they are releasing.

We can agree that we'd like to see less demand, but there is currently a high demand, and it's more likely to grow with population than to shrink with efficiency, unfortunately.

I'm not proposing that biomass is flawless, just a less-bad option than using coal to meet that demand.

Given a situation where the CO2 is likely to be released one way or another, wouldn't you rather it come from a batch that was sequestered post industrial revolution, in a woodland that now has a space open for new growth and re-uptake of that carbon (even if not 100% of what was released) than to add subterranean carbon into the equation?
Treacodactyl

That does not mean that there is no biomass re-growth and carbon sequestration.
Also it's glossing over the fact that young forests sequester carbon at a faster rate than old forests, and that's not even bringing into the equation the (debated) notion that "stable" old growth forests are carbon neutral, not sequestering any more than they are releasing

It could mean there is no sequestration if the trees aren't replanted. When you say young forest what age to you actually mean? A young sapling will not be absorbing much CO2, nothing like the amounts dumped into the air. when burning a large tree. What about all the CO2 pumped out cutting, processing, drying, shipping the biomass?
Slim

When I mention young trees I'm referring to trees under 20 or 25 years old. It's true they won't have the capacity to uptake much in those first 5 or 10 years. Again this gets in to the murky assumptions of what systems are being used. (clearcut mountain sides and just see what happens, or selectively log sections of land and release the undergrowth saplings, or plantations/coppiceland, etc.....)

We're clearly coming from different perspectives.

I may be biased in that I live in a region where the default state is forest. If land is left alone it reverts to forest. I realize that is not always the case globally.

Neither one of us have the real numbers here (if they exist at all) so I'm going to call it a day on this (I need to stop procrastinating on some other work!)

While I know that there are horrible examples of biomass done improperly, that is not the perception I have of North American biomass energy production, and forest stewardship.

I'd love to know what the global average is, in terms of re-planting, regrowth, etc., but I doubt that's available. (at that point they'd just be able to say "were burning this much and the area the biomass came from is now re-absorbing x% of that at y rate per year." and that would be immediately comparable against coal)


Quote:
It could mean there is no sequestration if the trees aren't replanted.


While this undoubtedly occurs (and even then, there would be sequestration as species that weren't planted by man would grow anyway), we clearly know it's not the standard. I feel as though you're trying to make it seem like we're just cutting everything and leaving deserts behind.

The question is what percentages of biomass production land have which standards applied?

Then the next question is can we improve the practices in the places they exist? If not, can we stop the harvest in that area all together?(economic forces)

This isn't all or nothing. "Some biomass is bad" doesn't mean all biomass is bad.

I guess I don't understand what you're arguing for.... Do you want to stop all biomass energy schemes? Do you want to stop all poorly executed biomass energy schemes? Do you want to improve how biomass is done, or get rid of it? If you want to get rid of it, how do you want the power currently generated by biomass to be generated?
Treacodactyl

I guess I don't understand what you're arguing for....

More honesty in the 'green' sector and better regulation. A quick google comes up with this and it's hard to argue with some of the ideas, i.e. only subsidising short carbon cycle biomass. https://www.carbonbrief.org/biomass-subsidies-not-fit-for-purpose-chatham-house
Mistress Rose

I read about half of that and came to the conclusion that the people writing it didn't know anything about forestry. Sorry, but most of that is a load of rubbish. In some places trees are stripped from the landscape, which then becomes desert. This is most likely to happen around deserts and the wood is used by the locals for cooking fires. In other places such as the Amazon and Indonesia trees are stripped to provide land for things such as cattle and palm oil plantations. A lot of the timber is burnt on site as it is uneconomic to move it. Medium to long term these areas could become denuded and potential deserts, although if left alone will probably reforest eventually.

In places that are worked for biomass the trees either regrow naturally as coppice or natural regeneration (you try stopping that in some British woods), are replanted, or are just being thinned. Most of the biomass that we get in the EU will come under this category if not all. Anything in the UK is watched over by the FC, and most parts of Europe have just as heavy control, as do Canada and the US. We are not considering here the cutting of virgin forest that would be better left, just any forest. There is no need to cut virgin forest but if it is cut it is usually for the unusual size of the trees, not for biomass.

I agree that biomass is the least energy efficient way to burn wood, but it happens to be the most convenient for power stations. They do not burn wet wood either I wouldn't think; it would be allowed to season either in the log or in the heap. In the UK anything stored outside; wood or coal will be at about 20% humidity, and may need further drying before use. Gas is often wet when extracted, so will need some sort of drying before use too.

No, biomass is not the 'ideal', but at the moment it is one of the best ways we have of covering at least part of the base load. If you want less transport, then coal is the answer, but importing gas from Russia seems a bit risky as well as using energy, as does importing oil from areas that are always a bit unstable politically.
Treacodactyl

I read about half of that and came to the conclusion that the people writing it didn't know anything about forestry. Sorry, but most of that is a load of rubbish.

Care to give a specific example, the article doesn't contain anything I saw that was disputed. Again you refer to coppice, as you know pine does not coppice, mature broadleaves will often struggle to coppice. Clear felled mature woodland may not grow back in a similar way etc - I don't know why you suggest otherwise. There seems to be plenty of question marks about how well managed the tree felling is in the US as well, so yes we are considering the cutting of virgin forest (old-growth I gather they call it in the US).
Slim

I read about half of that and came to the conclusion that the people writing it didn't know anything about forestry. Sorry, but most of that is a load of rubbish.

Care to give a specific example, the article doesn't contain anything I saw that was disputed. Again you refer to coppice, as you know pine does not coppice, mature broadleaves will often struggle to coppice. Clear felled mature woodland may not grow back in a similar way etc - I don't know why you suggest otherwise. There seems to be plenty of question marks about how well managed the tree felling is in the US as well, so yes we are considering the cutting of virgin forest (old-growth I gather they call it in the US).

I'm not sure what will satisfy you in terms of forestry responsibility.
P.S. there is very little old growth forest left in the U.S., and it's primarily in national parks)

Also, are you suggesting that US forestry has no standards or rules? It can vary by state, but there are definitely rules and standards. For example, loggers keep complaining they'll be put out of business because water quality rules keep getting updated in my state......
Treacodactyl

Also, are you suggesting that US forestry has no standards or rules? It can vary by state, but there are definitely rules and standards. For example, loggers keep complaining they'll be put out of business because water quality rules keep getting updated in my state......

No, but it's very hard to find out what is going on. From one side you hear the words 'waste' and 'thinings' and from the other you hear comments that the waste has been used for years to make other products and the majority of biomass is fully grown trees.

What is clear is the biomass demand has grown very rapidly in the last decade so I can't see how forests could have been planned, planted and managed for it several decades before.

There's also plenty of stories such as this: http://www.dailymail.co.uk/news/article-3113908/How-world-s-biggest-green-power-plant-actually-INCREASING-greenhouse-gas-emissions-Britain-s-energy-bill.html although I tend to expect it to be simply dismissed so I've avoided posting it up. I would be curious to know what is going on as there's plenty of people against the biomass market in the US.
tahir

I guess I don't understand what you're arguing for....

More honesty in the 'green' sector and better regulation.

Agree, as the recent NI wood fired heating scandal shows most subsidies in the UK end up as ways of fleecing the system with no environmental benefit
Slim


There's also plenty of stories such as this: http://www.dailymail.co.uk/news/article-3113908/How-world-s-biggest-green-power-plant-actually-INCREASING-greenhouse-gas-emissions-Britain-s-energy-bill.html although I tend to expect it to be simply dismissed so I've avoided posting it up. I would be curious to know what is going on as there's plenty of people against the biomass market in the US.

I'm glad that scrutiny is taking place.

However, I'm frustrated that the article doesn't address what is apparently the main thrust of its thesis, regarding carbon emissions.

Okay, so it's been posited that more CO2 is being released than promised. They don't say how much that is, nor do they give an accounting for how much is expected to be taken back up the harvested forestland over the next however many years, nor do they compare the difference of those numbers with the amount of carbon that would be released by generating an equivalent amount of power from coal. Which really is what the debate is about, is it not?

As for the harvest and regrowth standards, it's good that they focused on them, as that is probably the most concerning. I trust the forester they quoted who mentioned that the timber wasn't of commercial value as saw logs. It probably would go as cordwood for woodstoves traditionally.

As to the subtitle that American forests are being raped, I'd suggest that you can't rape the willing, in the sense that the landowners are not being forced to sell their product.

The concern I have from that article is not knowing the specifics of how that forestland's regrowth is being handled. I don't know that any of us can speak to that with any authority, so we're left looking at both sides and discussing the carbon. (or not discussing it)
Treacodactyl

As for the harvest and regrowth standards, it's good that they focused on them, as that is probably the most concerning. I trust the forester they quoted who mentioned that the timber wasn't of commercial value as saw logs. It probably would go as cordwood for woodstoves traditionally.

Or more likely not cut at all? I bet if the wood biomass exports were stopped overnight less trees would be felled.

As for a better breakdown of CO2 numbers that would be useful to see, along with a detailed breakdown of exactly what timber is used and how it is processed. That would take time though and require someone to pay for the research.
Slim

Well, my support for biomass in general still exists, but you've certainly given me more things to keep an eye out for, and some reasons to be skeptical.

For one, I had no idea there was such an international trade in wood pellets.

As an alternative story: The biomass plant we have near me is just wood chips, and I think the only post-grinding processing they get is drying with waste heat from the generating plant (if that).

Quote:
Mostly the wood comes from within 60 miles of the station. Ninety-five percent comes from logging residue and cull material created when harvesting higher value wood products. Harvests are conducted in accordance with strict environmental standards specified by the [State] Public Service Board.

The wood is chipped at the harvest site and delivered in trailer trucks to the plant or to a railcar loading facility; at least 75 percent comes by rail. A small portion arrives in an unprocessed form that can be stored and chipped when needed. [The] Station also purchases lumber-making byproducts such as bark and shavings or clean urban wood waste.


Quote:
Most harvests are partial cuts designed to improve growing conditions for the remaining trees. When a new crop of trees needs to be created or when wildlife habitat improvement practices require it, small areas may be cleared after approval from a professional forester. [The generating station] also receives wood from site conversions for development or agricultural expansion. [Our] foresters monitor each harvest operation to see that wood is harvested properly. The station’s wood suppliers are required to conduct their activities in accordance with strict standards to protect the environment.


Quote:
[The generating station] is equipped with a series of air quality control devices that limit the particulate stack emissions to one-tenth the level allowed by state regulation. [The generating station]'s emissions are one one-hundredth of the allowable federal level. The only visible emission from the plant is water vapor during the cooler months of the year. In 2008, [The generating station] voluntarily installed a $12 million Regenerative Selective Catalytic Reduction system, which reduced the Nitrogen Oxide emissions to 1/3 of the state requirement.


It's where every arborist and homeowner in the area brings their woody waste. They also go through a fair amount of pallets
GrahamH

Climate Change is difficult to question in my opinion due to the large amount of false data put out by supporters of both sides of the argument.
I personally do believe there is a change happening; why, I have no idea. There are some that argue that carbon dioxide is a good thing and that the world has never been greener.
What I do have trouble in believing are the climate change models.
I am not alone in this disbelief.

https://en.wikipedia.org/wiki/List_of_scientists_opposing_the_mainstream_scientific_assessment_of_global_warming

There are some notable scientists who say we have just begun the start of an ice age.
What the heck is the ordinary person supposed to believe!
Mistress Rose

Good question Graham. I am sure I don't know the answer.

Treacodactyl, if you get your scientific information from the Daily Wail I am afraid you won't get a very high level of information. Reading that my general opinion was So?

Thinning is when you cut some trees in a stand down so that the remainder will have more room to grow. In completely natural woodland a lot of trees will grow up together, some will die because they can't get the light, and sometimes too many will get too tall and thin and blow over. In plantation and managed woodland a thinning is done every 10 years or so in the UK. This allows the remaining trees to grow to their full potential. No, the plantation in many countries wasn't grown for woodchip; in the wood we are working, the beech trees were planted for paper pulp (would now have to be sent to Scandinavia to be processed), and the larch for pit props (a lot less call for that now). We are now thinning the beech for firewood mainly, although some good trunks are being milled, and the larch is mainly going for outdoor structural use and some for woodchip for various purposes.

I can see that the 'shock horror' cutting of those trees in the US that the environmentalists trecked through bog to see cutting could easily be suitable for pelleting. They don't seem to be of much commercial use for anything else and if the owner wants to replace them with a more suitable species, or a commercially useful one, that is up to him, although I would hope that there was state or federal rules that he has to conform to. In the UK, if it wasn't a sensitive site, the general rule these days is native hardwoods, but no idea what it would be there.

I would much prefer to send our brash for pelleting than leave it on the ground where it is a hazard to us working, and incidentally isn't popular with people walking in the wood because it 'looks untidy', but the stuff that we can't take is very bulky and wouldn't be worth while energetically to extract.
Treacodactyl

Treacodactyl, if you get your scientific information from the Daily Wail I am afraid you won't get a very high level of information. Reading that my general opinion was So?

That's rather ironic considering the people moaning about Trumps attitude to some press. Laughing To be clear I posted a link to a BBC report first, then Carbonbrief.org which you dismissed without valid reason and only the DM to illustrate a possible point. Whatever your view on various news outlets I'm sure we can all agree that occasionally some to some investigative journalism that does point out various problems.

I am fairly aware of what thinnings are in the UK but this is where my comment about honesty comes in. The wood pellet users mention brash, thinnings etc but it seems clear the majority is fully grown trees. It would seem honest to state this and then perhaps explain why they are cut if a whole area is not going to produce many saw logs why cut? If it is to produce biomass then say so.

Now after beating around the brash for a while we're down to the question should we have any concerns about importing millions of tonnes of woodchips/pellets from trees that are felled purely to produce them?
Mistress Rose

The vast majority of trees in heavily populated regions are grown for a crop, whether that be honey, saw logs or wood chip. Yes, it would be better to say that some trees are grown for wood chip/pellets, but what would be the alternative there? Either let the trees grow naturally and fall down into the boggy ground, or plant crop trees there? Either way you end up with trees being burnt or rotting. I would dispute trees rotting not producing methane. Near here anything that rots in the clay turns to methane.

Yes we should have concerns about importing wood chip, perhaps slightly less about pellets from the risk of pests and diseases. Otherwise, as Slim and I have been pointing out, it is probably less bad than importing millions of tons/cu m of coal or gas from politically unstable countries. These also need machinery to extract them, and a lot of fuel to transport them, and as Slim has been saying, we are then releasing carbon that has been stored for millions of years, not just a few decades. The ideal of course would be to use something like water or wave power as the base load, but that just isn't possible at the moment.
Treacodactyl

I couldn't find out much about what the trees would have been used for if there was no biomass market. If they were grown for crop what was the original use and what is being used for that now? In the UK if we suddenly produced millions of tonnes of extra wood biomass you'd see a big change in the market. Possibly the first to go would be firewood and many people would probably turn back to coal. Less wood for building might mean more concrete is used.

I'm puzzled by your comments on methane, dismissing the DM for not being scientific then dismissing scientific reports because they disagree with your view. I thought it was generally accepted boggy ground is very good at locking away carbon (isn't that how coal was formed?). Sorry but I'll take a lot of convincing to believe felling trees from boggy ground is environmentally friendly.

And going back to the original point about what's best, up to 5x more CO2 from woodfuel than coal well that would depend on what the climate is likely to do in the shorter, 10 -50 year, term. That's a question for the climate models, I bet some would favour coal or gas.
Mistress Rose

Boggy ground will absorb methane and other gasses as long as it isn't disturbed, but any disturbance can release it; the origin of Jack o Lantern I understand.

I was rather perplexed with the statement that wood releaxes 5x the amount of CO2 than from coal, then realised that that is to do with the amount produced per therm. Wood is less carbon dense than coal and so less thermally dense.

Perhaps we will have to differ on this. I don't think thermal power stations are ideal, and do have a lot of drawbacks, but feel they are a stage in the evolution away from fossil fuels.
Ty Gwyn

https://theenergyadvocate.co.uk/2017/02/27/450m-green-subsidies-spent-burning-wood-pellets-drax/ Mistress Rose

Thanks Ty Gwyn. I think that was a rehash of an article that Tre. posted. Ty Gwyn

This is from 2014 but relevant to the situation with some good info,even if you don`t believe the daily mail,

http://www.dailymail.co.uk/news/article-2581887/The-bonfire-insanity-Woodland-shipped-3-800-miles-burned-Drax-power-station-It-belches-CO2-coal-huge-cost-YOU-pay-cleaner-greener-Britain.html
Slim

Thanks for the second link Tv Gwyn. When you ignore the tone at which its presented, the information presented is pretty helpful to this discussion

"replacing coal with sustainably produced wood pellets reduces lifecycle emissions of carbon dioxide by 74 to 90 per cent."

"So Drax claims that burning wood ‘significantly reduces greenhouse gas emissions compared with coal-fired generation’ – by as much, Burdett says, as 80 per cent."

So, you can argue about whether or not gov't subsidies should be used, and how long it takes forestland to re-grow, but at the point at which the woodland has re-grown, the comparitive CO2 emissions are quite a bit lower from the biomass.

In 100 years time when that area is logged again, the CO2 being re-released is from now - 100 years from now.
Treacodactyl

Thanks for the second link Tv Gwyn. When you ignore the tone at which its presented, the information presented is pretty helpful to this discussion

You mean when you ignore any of the stuff that disagrees with your point of view? Wink

If you take that report at face value then what it shows is you can't rely on what has been said by the pro-biomass companies as they're are even contradicting themselves in that report.

Also the more recent research I linked to seems to have dug deeper, for example the 'waste' products used may have previously been used in a way that locks up their carbon rather than release it, so burning coal would be better without question (gas better, reducing usage best).
Slim

I'll be honest that I didn't read the whole thing thoroughly.

But the only numbers they presented didn't suggest anything all that bad about biomass, it was just tone in which they were presenting them.

No one is being quoted, they're all "admitting" and "claiming" things. Sounds like this paper would try to make postal delivery sound like scandal.

Quote:

Pressed by The Mail on Sunday, Enviva yesterday admitted it does use whole trees in its pellet process. But according to spokeswoman Elizabeth Woodworth, it only pulps those deemed ‘unsuitable for sawmilling because of small size, disease or other defects’. She claimed such trees, no more than 26 inches in diameter, make up a quarter of the wood processed at Ahoskie. Another 35 per cent comes from limbs and the top parts of trunks whose lower sections went to saw mills. To put it another way: 60 per cent of the wood cut by the loggers who supply Enviva is turned into pellets.


If that's not a B.S. presentation of information than I don't know what is.

I never said the North Carolina logging operation was necessarily god's gift to earth. But I also don't think they're likely to be breaking any rules or standards.

When you're saying 35% of the wood going through the mill is waste from trees that are actually used for lumber and/or furniture, and then turning around and using that to say 60% of the wood cut by loggers is turned into pellets, you may be technically correct, but in a stupid annoying way.

So why get all in a huff that they're turning the slash (limbs, etc) in to pellets? Isn't that where you want the pellets to be sourced from?!

If you want to dispute some of the practice, dispute the small trees that make up 25% of the mill's activities and go to pellets in their entirety. (though as the article suggests, they're at least purported to be processed in that manner because they've been deemed unsuitable for other purposes, and/or unlikely to grow to become suitable. I can pretty much guarantee you that they're not cutting down saplings with potential to become nice valuable saw logs)
Mistress Rose

I would love to know how the rubbish can be used to make something that will lock in the carbon Tre. Perhaps we could find a use for our brash that way.

I agree with Slim; you can't use all trunks for saw logs as they are unsuitable. Have you ever seen a bit of timber for furniture (apart from art furniture) that has a knot the width of the whole thing in it? It would fall apart. Sorry, but we have trees that we fell, mainly for firewood, and very few are suitable for saw logs. It will be the same in the US.

No, they are probably not using best practice, but if you replace the wood, as the article suggest, with gas, or coal, you are burning 100% fossil fuel. Exaggerated claims about carbon neutrality are not the same thing as burning gas or coal. Do you want to go back to those, and if not, what is your alternative?
Treacodactyl

I would love to know how the rubbish can be used to make something that will lock in the carbon Tre. Perhaps we could find a use for our brash that way.

One of the very common uses for milling saw dust (waste) is particle board, chip board, fibre board etc. Some of the fibreboards in our current house must be over 60 years old now.
Treacodactyl

I never said the North Carolina logging operation was necessarily god's gift to earth. But I also don't think they're likely to be breaking any rules or standards.

From the above link.

Quote:
In North Carolina, this will not be easy: as Carter points out, there is very little local regulation.


I'd guess the UK is more heavily regulated but even here I often see the rules and regs ignored or 'worked around'.

As for using brash for biomass then yes that may make sense. I'd like to see more brash and genuine wood waste used from the UK first as I know much is burnt on bonfires or chipped and left to rot, while we import stuff. I'm more nervous about importing it as it's prone to losing its traceability, is it really waste or are people being encouraged to cut stuff that would be left for wildlife?

However, when it comes to using thinings you need to be honest, what were their previous uses? Are they really thinings from a working wood or are you using that term to imply your more sustainable than you are?

It all goes back to what I've said a number of times, I want a clear statement of what is used and I'll add I would like to know how long clear felled areas will take to regrow and how much extra greenhouse gasses are released due to the biomass harvesting (e.g. methane release when harvesting from bogging areas).
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