EPA declares biomass power carbon neutral

[peakbagger]

http://www.powermag.com/epa-declares-forest-biomass-is-carbon-neutral/?pagenum=1

After the rigged Manomet study in Massachusetts, this is good news for the biomass power industry. It still may not save most of the plants as the price of biomass generation is still much higher than natural gas.

 

[begreen]

Unfortunately this determination is recent policy based and not scientifically based. The Alliance for Green Heat points out that biomass for home heating is much more carbon efficient than using it for power generation. Many of the changes and declarations from the EPA seem to be setting up some major lawsuits which only benefit the law firms.

 

[peakbagger]

Not sure if there is broad support that it is not scientifically based. Even the authors of the Manomet study ended up admitting that the study was rigged to come to a foregone conclusion. Unlike the majority of renewables biomass is dispatchable. Barring a pretty major technological advance with battery storage, a biomass plant is the only renewable that can inventory fuel and crank out power when needed.

 

[Circus]

Does CO2 emissions differ whether wood is burned or just rots on the ground?

 

[coutufr]

My understanding is that there’s no difference besides the fact that in the wood it is used by some living organisms. It is still the most ecological way of heating your house especially if you have a catalytic wood stove.

 

[peakbagger]

Does CO2 emissions differ whether wood is burned or just rots on the ground?

Yes and no. Its fairly complex. It depends on the how and what is rotting the wood. A pound of wood is only going to ultimately put out so much CO2 whether its burned or fully rotted. The tricky part is that natural processes may produce methane which is intermediate compound that has a far higher global warming potential than CO2. When wood is burned in a properly functioning boiler, the conversion to CO2 is pretty close to 100% especially if the unit has a downstream CO catalyst.

Where the grey areas exist is the energy used to collect and process the wood and the timespan looked at. Generally fossil fuels, specifically diesel, is used to harvest and transport the wood. The vast majority of diesel is "dynodiesel" derived from fossil fuels so even though the biomass is "green" it is being processed with fuels whose carbon is being dragged up out of ancient reservoirs thus the process is a net carbon emitter. If someone were stupid enough to grow trees strictly to burn for fuel this carbon burden is not shared with other processes. The reality is that no one grows trees to burn for power, the biomass fuel is a byproduct of other activities. Therefore the fossil carbon used to process the wood is spread amongst several ultimate products like high grade veneer, lumber, pallet wood, mulch and biomass fuel. If the other products are being produced and the biomass is left in the woods a large amount of the fossil carbon has already been expended to obtain the other products so only the extra fossil carbon used to process the fuel and transport it to a power plant should count towards the power production. Where things get tricky is comparing apples to apples with other lifecycle sources of power. Further complicating the comparison is the question is a KW of solar power on sunny day equal to a KW of power on a cloudy snowy day in the winter? The "Manomet" study played another game where they didn't look at the entire life cycle of the woods. If you take a snap shot of mature trees just before they are cut and then burn them in a power plant and take another snapshot after burning, the net result is a net large CO2 release. If you look at the overall cycle of the forest, as the trees regrow they will absorb CO2 through photosynthesis and they will be a long term CO2 sink. The net result in the long term is the CO2 is recycled over the lifespan of the forest with the exception of the fossil fuels used to manage and process the biomass products. Ideally the best thing for the environment is to let the trees stand but even then contrary to some folks beliefs is most trees have a distinct lifespan and eventually they will die off and rot. Most studies indicate that young growing forests are net carbon sinks but as they mature they transition to neutral.

The devil is in the details and in complex systems small manipulations in initial assumptions can yield widely varying results. I have no doubt that the recent declaration is far more political as was the past declaration in Mass that biomass power wasn't neutral supported by the flawed Manomet study was a political solution to preventing a biomass power plant from being built in the Berkshires.

 

[begreen]

Some thoughts on the topic from Woods Hole Research Center president.
(broken link removed to http://whrc.org/burning-wood-for-energy-is-not-carbon-neutral/)

 

[Circus]

Generally fossil fuels, specifically diesel, is used to harvest and transport the wood. The vast majority of diesel is "dynodiesel" derived

Never debate gasohol in a rural Wisconsin tavern.

 

[begreen]

Never debate gasohol in a rural Wisconsin tavern.

Might even be worse in an Iowa tavern?

 

[peakbagger]

Luckily for the benefit of the thread, the biggest US farm subsidy that isn't called one produces ethanol which is typically a replacement for gasoline. The logging and transport industry predominantly use diesel. Renewable diesel mostly comes from palm oil plantations in Indonesia with a small contribution from recycling waste vegetable oils (french fry grease). There have been various experiments growing oil crops in the US but none commercially successful.

 

[pdf27]

The devil is in the details and in complex systems small manipulations in initial assumptions can yield widely varying results. I have no doubt that the recent declaration is far more political as was the past declaration in Mass that biomass power wasn't neutral supported by the flawed Manomet study was a political solution to preventing a biomass power plant from being built in the Berkshires.

The other thing is what you do with the wood instead. Using the same timber to produce a super-insulated house and burning gas in a power station to drive a heat pump for the small amount of residual heat required is always going to be vastly better than burning wood for heat in an existing building, but are people ever going to actually do that?

 

[Circus]

produce a super-insulated house, but are people ever going to actually do that?

Improving efficiency is the first thing everybody does. Realizing the last 10% savings cost more than the first 90%, super-insulation is seldom financially sound.

 

[ihookem]

Everything is carbon neutral . The earth is carbon neutral. There is a certain amount of carbon on this earth. It can't get rid of it unless ya put it in outer space. You can drop it to the bottom of the sea and someday it will blow out of the ground like a volcano. You can burn it, and it will go up and come back down in the rain and be fertilizer just to make plants and trees grow more to make more carbon. Unless I a just plain stupid and missing something, it's not that hard. Although it did take the EPA how long to figure out a carpenter that hardly made it through high school. Could have saved millions of dollars, just had to ask a dumb carpenter .

 

[begreen]

Not quite so. There is a big difference between sequestered carbon and carbon released to the atmosphere.

" Carbon neutrality, or having a net zero carbon footprint, refers to achieving net zero carbon emissions by balancing a measured amount of carbon released with an equivalent amount sequestered or offset, or buying enough carbon credits to make up the difference. It is used in the context of carbon dioxide releasing processes associated with transportation, energy production, and industrial processes such as production of carbon neutral fuel."
https://en.wikipedia.org/wiki/Carbon_neutrality

 

[ihookem]

Yah , yah , yah , I know all that big talking BS. Carbon neutral, offsetting by buying credits. I've heard this for so long I dont believe it anymore cause all these people who talk about carbon neutral, sustainability are the ones that are dumping more carbon that anyone. Al Gore , all of Hollywood, flying all over in their Lear jets and building huge houses all over Aspen are the ones telling me I need to qui my diesel pickup. Tired of it all. Eventually all carbon gets released, noone can deny that , just look at the volcanoes. Carbon like crazy. The world will be fine. And actually , its fertilizer . All that carbon coming down with the rain makes the grass grow a lot better than well water cause carbon is in it. Take a bucket before it rains after a dry spell and you will see bits of carbon on the bottom of the bucket. Carbon, nothing more , nothing less. Without carbon ,I think we would die. . .No? Hell, all you old farts on this board aint nothing more than carbon. Anything that ever lived is carbon.

 

[begreen]

That philosophy has some holes that a hurricane could drive through. It's based on half-facts and denials. Excess carbon raining down is one of the serious problems, it's acidic. Not at all good for oceans. The earth can balance most situations pretty well, including volcanic burps. A major eruption like Yellowstone of course will have a lasting impact, but fortunately that only happens in very long time periods. Oil can lay trapped in the earth for millions of years and be no one's problem, but release millions of tons of that sequestered carbon in just a couple hundred years and the balance is getting upset.

Anyhow, it's apparent that anything old or young farts say won't change opinion, so no need to troll multiple threads. Have a nice summer.

 

[spirilis]

My main beef with the question of carbon neutral is, wood rotting on the forest floor takes years to decompose but burning releases all of it right NOW, so it has maximal greenhouse effect over time vs a slow trickle from decomposition.

The question of methane does complicate the matter. Also I am curious if temperature matters- slowly rotting wood may release cooler CO2 that may be preferentially taken up by nearby photosynthesis?

The rotting wood may also feed fungi that ultimately support the ecosystem of further growth and carbon sequestration (offering the minerals of the wood and the network of fungi to extract & shuttle it i.e. mycorrhizal fungi, vs just haphazardly dumping wood ashes and hoping for the best). I concede, however, that factor is one I have no numbers to support.