Burning trees and other biomass for electricity is not CO2 neutral as much as the UK gov wants it to be. First it produces more CO2 at the stack than coal and then you have to actually replant and wait 40 years.
Climate change is being driven by people extracting carbon from deep underground and releasing it into the atmosphere.
By that measure, burning biomass is CO2 neutral. The carbon released is not carbon which was extracted from the ground. It's carbon which was extracted from the air by plants.
All plant matter releases carbon dioxide as it breaks down anyway. Those trees which we burn as biomass weren't going to magically disappear - unless someone buried them they would eventually rot, releasing most of the carbon they extracted as they grew.
There are several concerns that gets left unanswered when people describe biomass as CO2 neutral. First is that modern growing of crops involve fertilizers, pumped fresh water, tractors/machineery, and transportation (biomass can not be compressed for easier shipping). The second issue is that in order to grow crops you need to clear out existing biomass in order to replace it with the crop used for biomass. Third people like to first talk about using it for carbon capture and green compensation for coal, oil and gas, only to later burn the same biomass under a CO2 neutral label.
Combined it make for a rather risky strategy for stopping climate change.
Those are all good points. Unfortunately there's a huge amount of noise in the green technology space, which has the tendency to drown out the scientific thinking.
However, I don't think dismissing biomass (or biofuels) completely is necessarily the right approach either. It's essentially a method of using natural processes to capture energy from the sun, and has the huge benefit of producing energy which can be stored indefinitely. Storing enough energy to get through renewable lulls without resorting to fossil fuels is an unsolved problem, and biofuels may be one of our best bets right now.
It would be interesting to see a full cycle efficiency analysis of biofuels - what percentage of the energy gained is used to grow and harvest plants, how much agricultural waste is currently burned/rotting without energy extraction.
Our strategy for stopping climate change right now seems to be "do almost nothing", which also seems rather risky to me. The quickest way to deal with it would be to use the market to drive innovation by applying a high tax on all extracted carbon. If renewable or carbon neutral energy was significantly cheaper than fossil fuels, the rewards for innovation would be much higher and so we'd see all sorts of interesting solutions. Right now green technology funding mostly exists in a subsidy driven top down command economy.
Unfortunately that requires political will, something that's almost entirely absent right now. People are all for green initiatives right until it actually effects how much they pay for fuel.
There is a massive difference between controlled burning at high temperatures in a power station and a little wood burner someone might have in their home.
Well, depends on how it's done. A wood burning stove in a regular one family house, where daddy is more concerned about the cost of the firewood than its water content is terrible yes.
A power/heating plant with proper monitoring of the combustion and filtering of the smoke is definitely no worse than a coal burning plant.
In the common case, yes, agreed. But again, it depends on how it's done. A lot can be done to increase efficiency and filter the smoke properly. I'm no expert but my understanding is that the technology in this area is well-established. Coal can be burned cleanly, and it's even economic to do so since more energy is extracted per unit fuel.
The main reason for refurbishing coal plants for other fuels or shutting them down entirely is that coal is terrible regarding CO2 footprint.
I dunno. I have an airtight stove as the only source of heat. We don't have gas or oil available out in the remote parts of Canada so wood heat is much healthier than freezing to death. Cutting, splitting, and hauling the wood keeps me in remarkably good health and the design of an airtight stove and functional lined chimney stack means I don't breathe smoke or particular matter and efficiency is remarkably high.
The wood used is not fed with industrial fertilizer, it doesn't require clearing the land to grow, and it doesn't require irrigation or ongoing maintenance. 100% of the carbon it contains was sucked out of the air not mined from the foundations of the Earth. It is completely carbon neutral.
I would go as far as saying wood heat is fantastic for human health.
Wood fires around your home: yes. Wood fires in power plants, instead of coal: probably not a big deal. Power plants already have extensive measures in place to clean their smoke.
If you do the maths there is not enough UK woodland area for the power they are producing.
I cannot find the source at the moment but at least in the UK they are basically importing wood chips from US, Canada, Malaysia, etc. just to keep the existing "bio mass" incinerators burning.
Yeah the biomass thing in the UK is an absolute joke - cynical greenwashing. So much of what I hear makes me question whether Oxbridge humanities graduates should be kept far, far away from any decision making involving science:
'James Woodley, an Environmental Biologist and resident of Northampton County, North Carolina, an area severely affected by wood pellet production for Drax’s biomass burning, said: ‘Now that the forests are gone, so is the sense of community. Dust is everywhere, even people are breathing in dust and becoming sick from it. When Enviva [a Drax pellet supplier] moved to our community, and to other poor communities in the Southeastern US, the company promised to bring hope to the hopeless, to reduce poverty, but what they ended up bringing was truckloads of logs, daily, constantly barrelling through.’'
My major issue against it is that these businesses are getting massive amounts of government funding and tax incentives due to the "green" spin.
Effectively none of these business are actually profitable and would be insolvent without government help/cronyism. This money is pretty much wasted on these polluting businesses and is money that could be applied elsewhere towards the environment.
Only part of the biomass comes from waste, either from the timber mills or from tree crowns and undersize wood. The rest comes from trees which are harvested for this purpose. The areas is replanted for this purpose with a fast-growing species like Willow and Poplar. The result can not be called a forest, it is a dense plantation with a high turnaround time.
By that measure, burning biomass is CO2 neutral. The carbon released is not carbon which was extracted from the ground. It's carbon which was extracted from the air by plants.
All plant matter releases carbon dioxide as it breaks down anyway. Those trees which we burn as biomass weren't going to magically disappear - unless someone buried them they would eventually rot, releasing most of the carbon they extracted as they grew.