Guest post by Don Healy
February 4, 2021
From page 200 of the Princeton University Net Zero America Report we have the following quote”
“Biomass plays an especially important role because i) it removes CO2 from the atmosphere as it grows and so combustion of hydrocarbon fuels made with biomass carbon results in no net CO2 emissions to the atmosphere, ii) it can be converted into H2 while capturing and permanently sequestering its carbon, resulting in a net negative-emissions fuel, and iii) it can similarly be used to make negative-emissions electricity.”
This supposition seems to be prevalent in many studies to achieve net zero carbon emissions and the idea of using biomass to meet climate objectives has now become acceptable to the EU and adopted in a rather massive fashion. As I recall, biomass was not considered originally to be a non-carbon renewable resource, but in recent years has been adopted with a vengeance. As more scientists scrutinize this assumption and examine the facts of the matter, it would appear that this assumption is very highly questionable. Over the last few years there have been numerous reports that the EU has been able to rely strictly on renewables for various periods of time, however, it appears that perhaps the tabulators of these statistics have been gaming the system.
The inclusion of biomass as a renewable energy source took place in 2009 when the EU committed itself to 20 percent renewable energy by 2020. Several countries, including the UK started subsidizing the biomass industry and by 2014 it made up 40% of the renewable budget, and is currently about 60%, obviously a much greater share than sources like wind and solar that we normally consider as renewables. Much of this biomass feed stock comes from the United States, Canada and Eastern Europe where trees have been pulped, pressed into pellets, heat-dried in kilns and shipped Europe where they are used as fuel in retired coal fired power plants. The same trend is occurring in the U.S., but not yet to the same scale.
The UK has been especially aggressive in adopting biofuels and purchases about 75% of the wood pellets produced in the U.S. for use in power plants there. Below is a graph of the sources of renewable energy in the UK.
UK_Energy_in_Brief_2020.pdf
As we can see from the graph above, those sources that were previously considered renewable energy sources, namely hydro, wind and solar, made up just over 25% of the renewables in 2019, with biomass (next to the last line in the table above) making up approximately 35% , or more than 1.4 times the amount of all other renewable energy sources, and this from a sector that much of which was not even considered renewable prior to 2009.
Increase in renewable energy sources over time showing dominate role of biomass.
The theory is that biomass is both renewable and carbon neutral. An examination of the processes involved reveals that this proposition is not supportable with facts. Consider the following:
- Wood pellets have a relatively low energy density compare to the coal or natural gas they are replacing.
- Emissions of CO2 per BTU of energy produced from wood pellets is at best slightly less than, and in some cases higher than coal, and double that of natural gas.
- The toxicity of the airborne waste from wood burning is considerable. Not as bad as from coal, but certainly more hazardous than natural gas.
- Including the cost of harvesting the wood, processing and drying the pellets, and then shipping them thousands of miles further increases the carbon footprint of wood pellets.
- Simply leaving the trees to grow, if one is applying sound forestry practices would maintain a massive carbon sink.
- Wood burning also releases emissions such as nitrogen dioxide, which is 300 times more potent than CO2, and many other pollutants, many of which are carcinogenic.
- It is true that the harvested areas can be reforested and once again the reforested areas can begin to sequester carbon, but to provide the fuel necessary to meet our energy needs we will start by creating a monstrous carbon sequestration deficit such that it would be many decades, and possibly hundreds to years to reach breakeven, if ever.
The claim made by many of the producers and commercial users of wood pellets is that for the most part, just the waste portions and non-commercial vegetative matter is used to make the pellets, however investigators have found that this is simply not the case. For economic reason, whole trees are more commonly utilized, and in the U.S. much of the supply comes from the southern eastern U.S. where trees can reach commercial size in 30 to 40 years when harvested for lumber.
It would appear that a majority of the logs are of merchantable size and could be milled into lumber, obviously not meeting the waste material quality standard claimed. Numerous other operations in both the U.S. and Europe show the same quality issue. It should be pointed out that if lumber is produced from the harvested tree, a majority of the carbon will be sequestered for an extended period of time, perhaps hundreds of years. When converted to wood pellets and burned the carbon content, on average about 40% of the mass, is immediately dumped back into the atmosphere as CO2. The proponents claim that the clear-cut areas are immediately replanted, but a review of the growth process of basically all living things including trees follows a sigmoidal curve.
The trees being cut for wood pellets are just reaching the log, or exponential phase on the graph above. They are just entering the stage where they become most efficient at packing on mass, 40% of which is carbon absorbed from the atmosphere. The new trees that would be planted in their place will face many years of a much lower growth rate. If these trees are not being utilized for lumber, this is the very worst time to harvest them from the standpoint of carbon sequestration.
Has the validity of the assumptions that allow the consideration of biomass as a renewable energy source been questioned by others? The answer is a resounding yes. Scientist Bill Moomaw, now a professor emeritus at Tufts, is a co-author of the Nobel Peace Prize-winning Intergovernmental Panel on Climate Report, co-author of four additional IPCC reports, and an expert on carbon sinks argues that it is a tragically shortsighted view of both carbon accounting and our current climate predicament. (1)
In 2009, as Massachusetts began debating whether to treat biomass as carbon neutral, he dove into the science. By assessing carbon emissions from bioenergy, and the slow regrowth rates of a replacement forest, he concluded that biomass stood to be “a serious problem.” To Moomaw, the question of whether biomass was ultimately carbon neutral was less important than whenit balanced out. (1)
Along with Mary Booth, a colleague who brought the issue to his attention, Moomaw and the Conservation Law Foundation convinced state officials to limit subsidies for biomass under the state Renewable Portfolio Standard. Unfortunately, the state later allowed large subsidies for burning wood to heat buildings. (1)
The analysis was later confirmed by a colleague at MIT, John Sterman, who did the math, and confirmed that burning wood today would worsen climate change, “at least through the year 2100 — even if wood displaces coal, the most carbon-intensive fuel.” (1)
It’s for that reason that in January of last year, Moomaw joined a group of nearly 800 scientists from across the world in petitioning the EU Parliament to end its support for biomass. (1)
Ironically, it turns out that burning wood for fuel has very little if any advantage over burning coal, other than in using strictly waste wood for the endeavor, and much of the waste wood is so dispersed that in many cases simply leaving the small pieces and chipping the larger pieces to decompose and enrich the carbon content of the soil would be a more practical choice.
While our nation’s forests, particularly on federal lands, are overstocked and in need of thinning in many areas, clear-cutting as is done to produce wood pellets is an unnecessary waste of wood fiber. Partial cutting to thin stands, reduce fire hazard and maintain the vitality of our forest resource is the best way to increase the carbon sink potential of our forested lands. Additionally, the esthetics issues of clear-cuts has long been an issue of contention, and one that once the public becomes more aware of current practices regarding wood pellet production is sure to create a major backlash.
Some thoughts:
- The current practice of using trees as a renewable and carbon neutral option simple does not make sense in theory or practice. If we want to reduce our carbon emissions and yet still have uninterruptible power supply, we could start immediately by converting any existing operating coal fired plants to natural gas, and do the same with any old coal fired plants converted to wood pellets. This would reduce the carbon emissions immediately by 40 to 50%, and reduce pollution by an even greater amount. If carbon capture and sequestration does become economically feasible in the future it could easily be added to the gas powered plants and as the amount CO2 produced would be lower, the infrastructure necessary to accomplish this would be substantially reduced.
- If we want a non-carbon producing power source that is also capable of producing hydrogen which could be used to efficiently provide portable energy for our transportation needs and further reduce our need for fossil fuels, we need to add nuclear power to the mix. High temperature electrolysis is much more efficient than conventional electrolysis and much less polluting than the chemical means we currently use to produce hydrogen. Hopefully in the future, fusion will replace fission. In the meantime, the new technology nuclear power plant designs provide safe and efficient means of generating sufficient uninterruptible power to balance out the inconsistencies that are an inherent part of wind and solar sources. Perhaps it is time for the developed nations of the world to create a new Manhattan Project to decide on and develop the very best and safest nuclear plant prototype(s) to provide consistency and cost saving to said development worldwide. The trend over millennia has been for mankind to move towards those fuels that have the highest energy densities; wood to coal to oil to natural gas and more recently to nuclear fission and perhaps in the future to nuclear fusion. The trend is obvious. To paraphrase Winston Churchill’s comment about Americans and apply it to the energy sector, the powers that be will do the right thing after they have exhausted all other options.
- A short review of history will reveal the fact the much of Europe, China, the Holy lands and many other areas were severely deforested to meet mankind’s home heating and commercial energy needs in the past. With the adoption of coal, some of the European areas have reforested, but China is just now going through a massive reforestation project to reverse the earlier damage. We do not need to revisit the errors of our past when better, rational options are so close at hand.
Sources:
- https://www.vox.com/science-and-health/2019/3/4/18216045/renewable-energy-wood-pellets-biomass
- https://futuremetrics.info/wp-content/uploads/2013/07/CO2-from-Wood-and-Coal-Combustion.pdf
Globalized charcoal burners. There is an ever widening barren zone around many third world cities where wood and charcoal are the most prevalent fuels. Pushing biomass as a sustainable green alternative to fossil fuels takes that activity and applies global market forces to it.
I appreciate that woodcutters would like a piece of the Great Reset but the effect a global biomass market will have on fragile ecosystems will be devastating. Please do not tout best practices. In a global market, very few operators will be following best practices. Neither will they be trying to establish biomass plantations, at least not until they have exhausted the supply of cheaper sources.
There has been significant destruction of tropical forests from the pressure for palm oil plantations to feed the biofuel scheme. Biomass as fuel will take that devastation and increase it exponentially.
Fossil fuels were the best thing that ever happened to earth’s ecology, in its interaction with a growing human population. In areas where propane, natural gas and electricity are available at reasonable rates, pressure on surrounding forests and brushland have been nearly eliminated, with the added benefit of much cleaner air. Our fossil fuel reserves give us a 200 to 400 year buffer to find cleaner and more sustainable energy sources.
I doubt that any negative impact climate change may bring will be as bad as what is being forced on us by the the Watermelons. They will strip the earth bare and cover it with windmills, solar arrays, biomass generating stations and a net of millions of miles of electric cable. This, they want to do in the next thirty years, not over the hundreds or thousands of years it would take for any negative impacts of climate change to take effect, assuming anyone will notice the changes.
The catastrophe is in climate change policies, not the climate. Well, what else could be expected after seeing how the Xi virus has been handled, particularly when Covid-19 policies are now supposed to be the framework for the Great Reset?
I think this site can do better than publicize the work of the two worst anti-forestry extremists in the East – Willie Moomaw and Mary Booth.
https://www.facebook.com/MikeLeonardConsultingForester/photos/?tab=album&album_id=2008688145878015 – Exposing the lies of anti-forestry extremist Willie Moomaw.
William Moomaw, the anti-forestry extremist, is also a fake Nobel laureate.
Source: https://nofrakkingconsensus.com/2021/01/25/the-climate-summits-fake-nobel-laureate/
Moomaw also founded a training center for environmental lobbyists. The public has been paying, via student subsidies and research grants, for people to receive academic degrees in this kind of activism. That’s a serious problem because NGOs, the World Bank, and other UN organizations have no democratic oversight. They aren’t answerable to the public. There is no mechanism by which the public can fire/vote out the leaders of these entities when they pursue policies at odds with the public’s priorities. Targeted, organized influence over public policy, absent public accountability, is a disaster in slow motion.
Source: https://nofrakkingconsensus.com/2021/01/27/the-fake-nobel-laureate-the-climate-ceo/
So fake Nobel Laureate Moomaw and his cronies are training job killing lobbyists while professing to be experts on forest management. These are the kind of people that have lobbied to cripple the forestry sector costing thousands of jobs and causing our forests to be degraded.
Mary Booth is another know-nothing anti-forestry extremist. I expose her here: Mary Booth, Portrait of an Anti-Forestry Extremist: https://www.facebook.com/photo/?fbid=2720773334662667&set=a.107449662661727
Next time do some research like I have:
Silvicultural Practices to Mitigate Climate Change: https://www.facebook.com/MikeLeonardConsultingForester/photos/a.618876954859148/1101423499937822/
Switch to Wood Heat and Watch Emissions Plummet: https://www.facebook.com/MikeLeonardConsultingForester/photos/a.618876954859148/1142901779123327/
I fully agree with your overall assessment, but on this particular issue they are correct. Certain battles require joining forces with parties you make disagree with on other subjects, and this appears to one of those situations.
Biomass Markets Support the Global Warming Solutions Act
The Massachusetts Global Warming Solutions Act requires a 25% reduction of Greenhouse Gas (GHG) emissions by 2020 and an 80% reduction by 2050. Deforestation and the urban heat island effect are responsible for up to 50% of the increase in global warming in the last century, thus protecting and managing forests are seen as a major part of the solution.
http://www.news.gatech.edu/…/reducing-greenhouse-gases…
Forests act as a major carbon sink but managed forests sequester more CO2 annually than unmanaged forests. Managed forests also produce many forest products such as lumber, pulpwood, firewood, and biomass which have many carbon benefits. Lumber and other durable wood products provide long term storage of carbon. Pulpwood, firewood, and biomass come from trees that are declining and not sequestering as much carbon as healthier trees. Firewood and biomass also provide heat and power which displaces fossil fuels. Increasing the acreage under actual forest management will enhance the carbon storage potential for existing forests in Massachusetts as well as providing many other carbon benefits. Managed forests are also less apt to be developed rather than unmanaged forests so carbon continues to be sequestered in those managed forests rather than being lost to development.
Biomass is, in essence, stored solar energy and is a byproduct of our forestry operations which allows us to grow more high quality sawtimber which is the main product. Increased markets for forest biomass have produced more forest improvement cuttings which help landowners: manage their woodlots to a high standard by greatly improving timber quality and species composition; improve wildlife habitat; generates income; increases property values as well as timber values; and encourages landowners to keep their land in forest. Biomass markets and improvement cuttings also provide many real green jobs right up the wood supply chain and help to provide many different forest products for consumers and a source of clean locally produced renewable energy.
The use of wood for energy is carbon neutral as long as the forests are growing faster than they are being cut. Here in Massachusetts, forests are growing many times faster than they are being cut. There are numerous studies that show the great carbon benefits of biomass utilization.
However, in Massachusetts less than ¼ of the forest growth rate is harvested, so tree mortality has greatly increased and carbon sequestration rates have declined significantly.
Declining Carbon Sequestration in Massachusetts Forests:
Forests store carbon as they grow. As forest stocking increases, tree mortality increases and net growth slows and eventually stops and sometimes declines. In the last decade, tree mortality has almost doubled. According to USFS data for 2014 (most recent), annual mortality of MA forests is about 600,000 cords per year which equals about 1.5 million tons. Our forests are releasing up to one ton of carbon per year (as much as 3 million tons/year) so a significant percentage of the annual growth merely rots so that now with the dramatic increase in tree mortality, carbon is being released at rates approaching the growth rate. So as net growth decreases, carbon sequestration rates also decrease.
Reasons for Tree Decline and Mortality:
Think about how a forest grows and develops. If you start with a bare field, then after 10 years you might have a few thousand seedlings/saplings/acre. After 100 years of growth (with no timber harvesting), there might only be about 200 trees/acre. So obviously a lot of trees die over time because they compete for space and light. To learn more about forest ecology and forest growth see this page on my web site: http://northquabbinforestry.com/forestry-practice/
Foresters like to speed up the natural thinning process by salvaging those trees that are declining and to favor the healthier better formed trees that will produce high quality sawlogs which are the most important forest product. So forestry is like gardening. To increase yields of the most desirable product (sawlogs), we thin out the weed trees.
The thinnings I mark are primarily from below which means that most of the trees removed are from the lower crown classes. This type of thinning accelerates the natural mortality of a forest stand as it develops over a long period of time by removing those undesirable trees that are of lower quality and/or are losing the race for survival due to natural competition. My thinnings typically remove about 1/3 of the basal area and consist of the lower quality white pine, hemlock, and hardwood sawtimber, pulpwood, and cordwood trees that have poor stem form and/or insufficient live crowns that will not support good diameter growth. The trees that are retained are the higher quality white pine, some hemlock, red oak, and other hardwood sawtimber and pole timber with good stem form and superior live crowns which will support good diameter growth. However, while doing so, we consider wildlife habitat (leaving some snags and den trees, etc.) as well as other resource protections such as wetlands and endangered species habitat.
But without active forest management like was just described, tree decline and mortality increases as a forest becomes over-stocked.
Besides overcrowding, other factors have also caused or will cause tree and forest decline and mortality:
Destructive Liquidation Cuttings: Liquidation cuttings, which are also called high-grading, diameter limit cutting, or “selective” cutting, are the hidden plague of private forest land. It is sometimes referred to as “cutting the best and leaving the rest”. It is the cutting of most if not all of the very best and high value trees such as red oak, sugar maple, cherry, and good white pine above a minimum size (usually 12-14 inches in diameter at chest height), while leaving the poorest and lowest value trees such as red maple, beech, hemlock, and low quality white pine.The destructive practice of liquidation cutting has occurred on the majority of private forest land in Massachusetts despite a Forest Cutting Law which was written to promote good forestry!
Since the healthiest trees with the fewest defects are cut, the overall health of the forest is reduced. The remaining trees are more susceptible to the damaging effects of insects, disease, and storm damage and less able to recover after these disturbances occur.
Since many of the trees that are left have been suppressed or are suffering from defects, they won’t grow as quickly as the better quality trees, so the value of the next harvest will be greatly reduced.
For more info on liquidation cutting, see this page on my web site: http://northquabbinforestry.com/liquidation-cutting/
The non-native insect pest the Hemlock Wooly Adelgid is causing significant defoliation which has led to much slower growth rates while hemlock tree mortality is increasing.
The non-native insect pest the Emerald Ash Borer has arrived in Massachusetts and will lead to widespread mortality of ash trees.
Gypsy Moth Caterpillar – 100,000 acres defoliated this year – the most since 1981. This will result in more mortality as secondary agents such as the two lined chestnut borer and shoestring root rot attack the weakened trees. The naturalized fungus entomophaga maimaiga had been keeping them in check but two dry springs in a row inhibited the spread of this natural control.
Non-Native Invasive plants such as oriental bittersweet, Japanese barberry and multiflora rose are spreading rapidly and now infest 7% of all forest land. These non-native plants displace native plants and inhibit new tree regeneration. In the case of oriental bittersweet, those vines can envelop, strangle, and cause tree mortality.
Why increasing the use of Biomass and Wood Pellets is good for the Climate:
Wood is the most successful residential renewable energy technology in the America today. Wood energy displaces more carbon than any other renewable energy!
Increasing markets for forest biomass allows the practice of good forestry and greatly reduces tree mortality. Carbon sequestration rates are highest in healthy young forests especially those forests less than 50 years of age.
In addition, salvaging declining and dying trees or tops that die and decay and using them for energy (even at low efficiency) has a huge carbon benefit. It enhances forest productivity and higher carbon sequestration rates.
1. The average home with an oil burner uses 700-800 gallons of fuel oil/year. Switching from oil heat to wood pellet heat reduces CO2 emissions by 90%! It can also save up to 50% in heating costs.
2. The payback period is shorter for wood stoves than for most other renewable energy technologies – http://www.forgreenheat.org/…/cooling_climate_change.htmlb
3. http://economics.mit.edu/files/7337 – This study by MIT shows it costs up to $600 to displace one ton of carbon using solar while it costs as little as $10 to displace one ton of carbon when using wood pellets instead of fuel oil! Thus wood pellets are up to 60X as cost effective as solar! Why are we subsidizing made in China solar anyway?!
4.http://harvardforest.fas.harvard.edu/…/Berlik… – In this paper by Harvard Forest entitled “The Illusion of Preservation”, the authors argue correctly that when we lock up or stop the management of our own forest lands, then we import more wood often from areas that don’t have our high environmental standards. So forest degradation and carbon emissions are simply exported. Hence, the “illusion”.
5. Wood pellets have a very small carbon footprint. Wood is a form of solar energy – converting sunlight and atmospheric carbon into carbohydrates whose energy can be released when we need it rather than when it hits us (like conventional solar energy).
Even wood pellets from a supply involving significant transport distances or that is produced with fossil-fired electricity will avoid:
• 90% of the carbon emissions attributable to equivalent natural-gas heating,
• 93% compared to oil-fired heating,
• 96% compared to direct electric heating, and even
• 90% compared to heat-pumps.
A low-carbon-footprint source of wood pellets will avoid:
• 97% of the carbon emissions from natural gas,
• 97.5% compared to oil-fired heating,
• 99% compared to direct electric heating, and
• 97% compared to heat-pumps.
Examples of Biomass Use:
Pinetree Power – this 17 MW ultra clean biomass power plant supplies renewable energy to the Fitchburg area with locally produced biomass harvested sustainably from well managed Massachusetts forest land.
Athol High School has been using wood heat for decades saving hundreds of thousands of dollars.
Mount Wachusett Community College. In 2002, Mount Wachusett’s main campus in Gardner, MA, had an 8 MMbtu boiler unit installed to replace an all-electric heating and cooling system, which was funded in part by the US Department of Energy and the Massachusetts Department of Energy Resources. By switching from heating oil, the college saves about $270,000 dollars per year.
Cooley-Dickinson Hospital has been heating and cooling their facility with biomass for 25 years and has received a national award for sustainable practices: http://healthcarenews.com/burning-with-energy-cooley…/
Quabbin Administration Building. In 2008, the Department of Conservation & Recreation’s Quabbin Administration complex installed a boiler that burns about 350 tons of wood chips per year and displaces 85% of the fuel oil previously being used. The total cost of installation was $480,000, with the payback period at 6 years.
Seaman Paper Co., Otter River, MA employs hundreds of workers and has reduced its greenhouse gas emissions by 91% by using biomass! – https://www.seamanpaper.com/sustainability.html
Harvard Forest’s new biomass system: http://harvardforest.fas.harvard.edu/biomass has greatly reduced its carbon footprint.
Harvard Forest’s Wildlands & Woodlands Project supports biomass: http://www.wildlandsandwoodlands.org/…/Conservation…
Air Quality:
The speculation that biomass power increases asthma rates because of the tiny amount of additional particulate emissions is false. Modern biomass plants – both electric and thermal – are very efficient, clean burning, and well within strict EPA standards. In addition, a peer reviewed study by the prestigious John Hopkins Hospital concluded that it is indoor air pollution that is the main cause of higher asthma rates.
Wood chip business is a racket. Poor and old people are freezing to death in last few days, since they have to choose between heating or food. Electricity prices in the UK are already subsidising this madness, and yet new price rise for the electricity was announced just the other day.
It is inhuman, it is not economic and it is not environmentally sound !
Entire Forests Being Murdered to Produce Wood Pellet Biomass
https://wattsupwiththat.com/2018/04/18/green-shock-entire-forests-being-murdered-to-produce-wood-pellet-biomass/
gone into moderation
“combustion of hydrocarbon fuels made with biomass carbon results in no net CO2 emissions to the atmosphere”
Coal is biomass, too, so can we not consider burning coal as net neutral? I say this in all seriousness. Coal and fossil fuels are just carbon dioxide that was stored away for a longer period than the CO2 of a still living or recently chopped down tree. The same is true of methane arising from the swamps of the frozen tundra when they thaw out and begin to decompose again. It’s just the slow combustion (i.e. decomposition) of biomass.
The arbitrary division of living biomass and formerly living biomass is silly. Once you chop down a tree, it’s formerly living, isn’t it? We will never emit enough CO2 from burning fossil fuels to get the Earth’s atmospheric CO2 content up to the levels it has previously been, when plant life flourished and created SO MUCH material from it’s dying detritus that it produced all the coal we find today. More CO2 in the atmosphere for C3 plant life is a precious resource being liberated from captivity. It is recycling of life.
I read wood produces 12 times as much mercury as coal.
Trot out the mercury scare tactics. If you read it on the internet is must be true!
During the debate on the ‘mercury rule’ for coal plants in the US, I checked the CDC site. No US children had levels of mercury about the threshold of harm from the environment.
Also read a study used to justify warnings about eating fish from Washington State waters. I thought the warning was odd because Washington State only had one coal plant at the time. The mercury in fish from two lakes were the result of legacy issues such as a smelter in Canada.
Fake scares are easy to identify because no smoking gun exists. Real evidence of a mercury problem comes with a measured level of mercury from blood to hair samples relative to a limit.
Where, pray tell, would the Mercury come from?
Biomass is more than wood pellets. My argument here is based on the prevailing thoughts about what constitutes a greenhouse warming potential (GWP). I am not arguing about the validity of whether there is GW, AGW or CAGW. I am just arguing that the maths allow for certain hypothesis.
There is a valid argument that when fermenting waste and collecting the gas to burn for heat you are turning a high GWP gas (methane) into a low GWP gas (CO2) and thus the net result is negative. That is, the methane would be produced from the waste in natural dacy processes and by burning the methane you get less greenhouse warming. The matter is highly debated, of course, since some feel it is important not to find solutions including the ability to use more energy.
Turning other biomass into methane still gives a fairly large reduction in net CO2 emitted, provided there are no methane leaks in the process.
Turning biomass into liquid fuel is a more energy intensive process, and thus there is more debate on the net effect of doing so. A biodiesel still emits NOx, particulates and other local pollutants. In fact, quite a few biodiesels increase specific NOx emissions.
A Norwegian statistician employed by the National bureau of statistics did hos PhD on using wood as biomass, and he concluded that using the boreal woods found in Norway would need a horizon of more than 100 years before any net reduction can be achieved. Basically he was saying that burning wood is a no-no if you are concerned about global warming. Needless to say he has taken flak from all around. Bluntly telling the truth tends to do that.