By Kenneth Richard on 1. November 2018
Governments vociferously promote bioenergy as renewable, sustainable, and carbon-neutral. But scientists are increasingly characterizing this “belief” as a “major error”, as bioenergy generates more CO2 emissions per kWh than burning coal does, and the projected rapid growth in bioenergy will serve to ‘increase atmospheric CO2 for at least a century’ as well as clear forests and destroy natural ecosystems.
Opinion: Reconsidering bioenergy
given the urgency of climate protection
“The use of bioenergy has grown rapidly in recent years, driven by policies partly premised on the belief that bioenergy can contribute to carbon dioxide (CO2) emissions mitigation. However, the experience with bioenergy production and the pressure it places on land, water, biodiversity, and other natural resources has raised questions about its merits. Recent studies offer a lesson: Bioenergy must be evaluated by addressing both the stocks and flows of the carbon cycle.”
“[A] major reprioritization of climate-related research, policy, and investment is urgently required, a move away from bioenergy and toward terrestrial carbon management (TCM). Researchers and policymakers must pursue actionable mitigation approaches that have the best chance of significantly reducing atmospheric CO2 concentrations in the near and medium term.”
“Bioenergy displaces land from prior uses, resulting in both direct and indirect land-use change. This leads to the difficult conundrum of carbon debt, i.e., the time it takes for the release of carbon stocks linked to bioenergy expansion to be paid back through future carbon uptake, which can be decades. Moreover, the realities of bioenergy production exacerbate the effects of industrial-scale agriculture on soil health, water quality, biodiversity, and other ecosystem services.”
“The assumption that bioenergy is inherently carbon-neutral, which is based on static forms of carbon accounting, is a major error (Haberl et al., 2012). Viewed objectively, it is quite a sweeping assumption: It asserts that a carbon flow into the atmosphere at one place and time (from bioenergy combustion) is automatically and fully offset by carbon uptake at another place and time (on ecologically productive land). Scientifically speaking, there is neither a sound basis nor a need to make this assumption. The extent to which the CO2 emitted from bioenergy use is balanced by CO2 uptake is an empirical question.”
“In short, a sound understanding of carbon-cycle dynamics shows that now and for the reasonably foreseeable future, the promotion of bioenergy is ill-premised for climate protection. This is particularly true if one respects the limited amount of ecologically productive land available for supplying food and fiber as well as sustaining and restoring biodiverse habitats.”
Does replacing coal with wood lower CO2 emissions?
Dynamic lifecycle analysis of wood bioenergy
“[G]overnments around the world are promoting biomass to reduce their greenhouse gas (GHG) emissions. The European Union declared biofuels to be carbon-neutral to help meet its goal of 20% renewable energy by 2020, triggering a surge in use of wood for heat and electricity (European Commission 2003, Leturcq 2014, Stupak et al 2007). … But do biofuels actually reduce GHG emissions?”
“[A]lthough wood has approximately the same carbon intensity as coal (0.027 vs. 0.025 tC GJ−1 of primary energy […]), combustion efficiency of wood and wood pellets is lower (Netherlands Enterprise Agency; IEA 2016). Estimates also suggest higher processing losses in the wood supply chain (Roder et al 2015). Consequently, wood-fired power plants generate more CO2 per kWh than coal. Burning wood instead of coal therefore creates a carbon debt—an immediate increase in atmospheric CO2 compared to fossil energy—that can be repaid over time only as—and if— NPP [net primary production] rises above the flux of carbon from biomass and soils to the atmosphere on the harvested lands.”
“Growth in wood supply causes steady growth in atmospheric CO2 because more CO2 is added to the atmosphere every year in initial carbon debt than is paid back by regrowth, worsening global warming and climate change. The qualitative result that growth in bioenergy raises atmospheric CO2 does not depend on the parameters: as long as bioenergy generates an initial carbon debt, increasing harvests mean more is ‘borrowed’ every year than is paid back. More precisely, atmospheric CO2 rises as long as NPP [net primary production] remains below the initial carbon debt incurred each year plus the fluxes of carbon from biomass and soils to the atmosphere.”
“[P]rojected growth in wood harvest for bioenergy would increase atmospheric CO2 for at least a century because new carbon debt continuously exceeds NPP.”
“[C]ontrary to the policies of the EU and other nations, biomass used to displace fossil fuels injects CO2 into the atmosphere at the point of combustion and during harvest, processing and transport. Reductions in atmospheric CO2 come only later, and only if the harvested land is allowed to regrow.”
A Critical Look at Forest Bioenergy:
Exposing a high carbon “climate solution”
“These nations fail to recognize the intensity of CO2 emissions linked to the burning of biomass. The chemical energy stored in wood is converted into heat or electricity by way of combustion and is sometimes used for combined heat and power cogeneration. At the point of combustion, biomass emits more carbon per unit of heat than most fossil fuels. Due to the inefficiencies of biomass energy, bioenergy power plants emit approximately 65 percent more CO2 per MWH than modern coal plants, and approximately 285 percent more than natural gas combined cycle plants.”
“Furthermore, the Intergovernmental Panel on Climate Change (IPCC) states that combustion of biomass generates gross greenhouse gas (GHG) emissions roughly equivalent to the combustion of fossil fuels. In the case of forest timber turned into wood pellets for bioenergy use, the IPCC further indicates that the process produces higher CO2 emissions than fossil fuels for decades to centuries.”
Are wood pellets a green fuel?
“Recently, attention has focused on woody biomass—a return to firewood—to generate electricity. Trees remove CO2 from the atmosphere, and burning wood returns it. But recent evidence shows that the use of wood as fuel is likely to result in net CO2 emissions and may endanger forest biodiversity.”
(press release) “Each year, some 7 million tons of wood pellets are shipped from the United States to Europe, where biomass fuels have been declared carbon-neutral with respect to fulfilling the commitments of the Paris Climate Accord. The current goal for the European Union (EU) is to generate 20 percent of its electricity by 2020 using renewable sources, including burning woody biomass. In part to revive a languishing forest products industry, the U.S. Congress may also declare wood a carbon-neutral fuel. … With wood, there is the assumption, but no guarantee, that new trees will be planted and persist long enough to pay back the carbon debt created by combustion of the previous stands. If that carbon stock is not restored, then burning wood may actually emit more CO2 to the atmosphere than burning coal. … [T]he recent science indicates that production of wood pellets for fuel is likely to put more CO2 in the atmosphere and maintain less biodiversity on the land during the next several decades.”
Increasing biomass demand enlarges negative
forest nutrient budget areas in wood export regions
“Increasing global woody biomass demand may cause additional pressure on forested ecosystems, enlarging negative nutrient budget areas.”
“In 2014, wood and agglomerated wood products, i.e. pellets and briquettes, provided almost half (45%) of EU-28’s total inland energy production by renewables. Current European renewable energy policy will boost woody biomass demand and, considering 2015 as baseline, the global woody biomass demand is expected to be 23 × 106 t a−1 in 2024 representing a 70% increase. For 2050, global woody biomass use for energy is expected to increase by 1.6 × 1010 t a−1 (obtained from 2.3 × 1010 m3 a−1 by assuming 0.7 t m−3 as average woody biomass bulk density) representing a potential energy production ranging from 2.7–3 × 1020 J a−1 (for a 1.7–1.9 × 1010 J t−1 biomass’ energy output). By the late 21st century, the biomass energy production is expected to be 2.4–8.5 × 1020 J a−1 13, which is approximately two orders of magnitude [100 times] higher than the 2016 biomass energy production of 1.8 × 1018 J a−1 14.”
Posted in Alternative Energy, Emissions, Green Follies |
And it took scientists to work this out?
The mind boggles.😂
And when they began the equally scientifically unsound policy of making fuel from corn, people in several parts of the world starved; making fuel was lucrative.
Mammon sometimes triumphs over science.
A quick look at the long established engineering charts would have enlightened scientists, and politicians, that wood produces much more CO2 than coal when burnt.
The solution by really clever and brilliant scis. and pols. was to plant more trees. Why not just keep on burning coal (less CO2), and plant more trees.
What a pitiful bunch.
When I was a child living at the home my parents owned, there was an ‘octopus’ coal-burning furnace in the basement of the house and a coal bin. Not much else down there, the furnace and coal required space.
You burned coal because it burns a long time, you don’t have to feed the beast so much.
You fed the coal into the fire box, removed ashes from the ash pit. Nobody used wood, you would have to chop wood until the cows came home. Coal is a far better source for heat. You burned coal, it is what you did during the winter to stay warm.
Coal was there for a reason, it burns a lot longer than wood, has more heat content. Heat rises, no electricity was required to stay warm, the coal and coal furnace were all you needed. A very simple system designed to cost very little to have.
If you can’t figure that one out, you’re not the sharpest tool in the shed.
Today in the post-modern world, electric heat is clean and convenient. The fire danger is minimized and the safety factor is an advantage.
You still burn coal at the coal-fired power plant, so the mess is miles away.
If you don’t want to use fossil fuels to live, dig a cave and live in the ground at 45 degrees Fahrenheit.
Won’t be so bad, but there are better ways to live in this world.
Great and realistic down to earth post sasquatch
Why do you continue to frame this in a way that implies this is the net result of burning biomatter/-gas vs. coal for the same amount of heat? As with so many other things you try to argue, you are leaving out half of the equation (the fact that biomatter/-gas gets “produced” instead of just burning down forest after forest).
Also …
This is true for everything that produces energy CO2 neutral. At a certain rate of buildup you won’t have any CO2 reduction with wind mills or solar panels as the CO2 debt for building new installations is higher than what current installations save. This is about the long run though …
If you were to read the papers you’d see it is considered a “belief” that the trees are always regrown to replenish, making this a carbon-neutral pursuit. By 2100, there is expected to be a 100-fold increase in biomass-burning, which is not sustainable and will denude the Earth’s forests.
Please actually read the papers – or even read the portions from the article. It is only assumed (or believed) that bioenergy is carbon-neutral.
But it’s counted as carbon-neutral right now, which is more and more considered as a “major error” in accounting. And for the future….
“[P]rojected growth in wood harvest for bioenergy would increase atmospheric CO2 for at least a century because new carbon debt continuously exceeds NPP.”
So the planet isn’t greening? Are we burning forests faster than they regrow? Are we producing biofuels from crops faster than the crops regrow? Hmm … I went to a few websites of companys burning wood. They all claim to use sustainable sources for their wood.
Who is expecting this? I don’t. I don’t think a country like Germany will further increase it’s biomass energy output/consumption (https://energy-charts.de/power_inst.htm doubleclick on biomass on this graph and see the current development).
It is carbon-neutral. Burning wood releases the carbon bound by the wood. It is not carbon-neutral when you don’t grow back the same amount of wood that you burn, e.g. your action reduces the total mass of available wood and thus is unsustainable.
When you have a stick, burn it and regrow that stick of wood to burn it again and repeat this forever … why do you think it makes sense to only look at the first iteration before you even began to regrow your fuel? Yeah, you’ll release amount X of carbon to the atmosphere and are X in debt. So let’s repeat it 10 times … you’ll have released 10*X carbon and absorbed 9*X through regrown wood (if you don’t count the final regrow phase towards the tenth iteration). So even if burning wood releases 3 times as much CO2 as burning coal, you’ll have released less CO2 to the atmosphere than burning coal would have during those 10 iterations.
Do you understand or will you stay with your story?
It’s greening, yes, especially in non-forested regions.
Venter et al., 2018
https://www.nature.com/articles/s41467-018-04616-8
“Over the past three decades, 7.5 million km2 (55%) of non-forest biomes in sub-Saharan Africa underwent significant net gains in woody plant cover. This is more than triple the 2.2 million km2 (16%) significant decrease in woody plant cover, confirming local-scale studies indicating increases in WPE [woody plant encroachment] over the last century. … These results confirm global greening trends, thereby bringing into question widely held theories about declining terrestrial carbon balances and desert expansion.”
In many places, yes.
By 2100, there is expected to be a 100-fold increase in biomass-burning
It is strongly suggested that you actually read the articles and the scientific paper excerpts before leaping to the comments.
That is a belief. Scientists — AGW advocates — disagree with this belief, and are increasingly publishing papers that say so.
https://www.scientificamerican.com/article/congress-says-biomass-is-carbon-neutral-but-scientists-disagree/
Congress Says Biomass Is Carbon-Neutral, but Scientists Disagree
How is it a belief? You grow something and then burn it. It can’t get more carbon neutral than this. If you start with burning stuff and then regrow it, I refer you to the last part of the comment you replied to.
“…premised on the belief that bioenergy can contribute to carbon dioxide (CO2) emissions mitigation.”
Belief = Assumption
“The assumption that bioenergy is inherently carbon-neutral, which is based on static forms of carbon accounting, is a major error (Haberl et al., 2012). Viewed objectively, it is quite a sweeping assumption: It asserts that a carbon flow into the atmosphere at one place and time (from bioenergy combustion) is automatically and fully offset by carbon uptake at another place and time (on ecologically productive land). Scientifically speaking, there is neither a sound basis nor a need to make this assumption. The extent to which the CO2 emitted from bioenergy use is balanced by CO2 uptake is an empirical question.”
Read the article with peer-reviewed papers in it, SebastianH. It’s pretty easy to understand…unless one is immersed in confirmation bias.
Kenneth, I know you argument or rather what those papers are trying to argue. Don’t act like I am somehow ignoring the „truth“ here.
Grow energy crops or a forest with fast growing trees and instead of burning the biomass, store it. Do you think that over the course of decades to centuries the patch of land will have accumulated more biomass on its own or in the scenario with a regular harvest?
It is only carbon-neutral if you sequester the CO2 at the same rate that you release it. That is only common sense. Otherwise you can argue that burning coal is carbon-neutral because it is only releasing CO2 from long dead wood and in the fullness of time trees will become coal again.
It is a question of the time lag, Seb. If you clear-fell a 20-year-old forest (and don’t tell me they aren’t because they are) and burn it in a month, it takes 20 years to re-sequester that CO2. That’s not carbon-neutral; that’s playing fast and loose with reality.
And if you fell these trees and chip them and ship them across the Atlantic to be burnt in a power station deliberately built on top of three centuries-worth of coal, that is certainly not carbon-neutral on any time scale and to pretend that it is is to insult the intelligence of a five-year-old.
Most engineers, especially electrical whose forte is energy have known this for many years……but thanks to Al Gore’s denigration of engineers in his “An Inconvenient Truth”…..political leaders and news media listened for energy solutions presented instead by climate scientists….JUST HOW STUPID IS THAT!
Al Gore presented this in his documentary….
“A man will not understand something when his paycheck depends on him NOT understanding it” – Upton Sinclair…..
That statement was aimed directly at engineers and techs working in the energy industries…..those most successful businesses who could afford to hire the most brilliant in the world of real science…..not to be confused with SCIENTISM, i.e., quasi-science infused with political corruption.
First you chop down a 100 year-old tree, then you chip it, with a diesel powered chipper, bale it and load it onto a diesel powered lorry/train, drive to an American East coast port, load it onto a diesel powered cargo vessel, sail 3000 miles to England, unload onto another diesel powered lorry/train and cart it to Drax, to be burnt to produce electricity.
PS Drax used to burn coal, it was actually built to take advantage of the close proximity of the mines.
Now tell me that burning biomass is carbon neutral.
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