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  1. But, what is the business case for burying wood waste?

    If I have wood waste, and I can get paid to sell it to a biomass plant, or I can pay someone to bury it, well the choice is pretty obvious for most people, isn’t it?

  2. I would expand this beyond wood waste a little. Downed trees in the wilderness rot and produce methane. Methane is a more powerful greenhouse gas than carbon. This is an added reason to burn downed wood for electricity if it is only going to rot instead.

    Additionally, one of the end uses for wood is paper. The digital revolution has seriously impacted the publishing industry and thus the need for paper. Here in Michigan, forest growth rates now greatly exceed end use for wood. [I believe on the order of 4 : 1, but I would need to verify that number]

    When these ideas are pieced together you can make a sustainable argument that burning wood is a net benefit in appropriate quantities.

    1. @Kevin Krause

      This is an added reason to burn downed wood for electricity if it is only going to rot instead.

      There is added complexity here because natural cycles depend on a reasonable level of rotting wood in forest settings. There are entire fields of study associated with the ecosystems created by fallen trees.

      1. @Rod

        I agree that some of the nutrients need to be returned to the local soil. I believe that forestry experts look for around a 2:1 growth/harvest ratio for healthy sustainable foresting. That is why a nearly 4:1 current ratio here in Michigan suggests that we may have space for more sustainable biomass electricity generation.

  3. I should add an argument on the opposite side. Collection and transportation of wood waste also burns fossil fuel. If the radius of the circle around the biomass plant is too large, then the shipping of the fuel ends up negating any benefits of burning the wood waste. Therefore biomass plants should be carefully sited near adequate fuel sources.

    As an aside, a couple years ago I read about a company in the US that was making wood fuel pellets and shipping them to Europe for consumption. I never saw the numbers, but I cannot fathom that being a carbon reducing or carbon neutral process. I presume it was a satisfactory economic arrangement, with no price of carbon included of course.

    1. There’s the potential for powering the collection machinery from biomass itself (e.g. diesel engines running on bio-oil, or spark-ignition engines burning syngas from bio-oil) but nobody seems to be doing any work along those lines.

          1. So, how good a fuel is scrap wood. Figure Jack Pine. This is probably pretty common in the land below the Mackinac Bridge.

            17.1 million BTUs per cord.

            Source:

            http://www.engineeringtoolbox.com/wood-combustion-heat-d_372.html

            How much gas would it take to equal this heating value?

            This link says about $12.60 / thousand cubic ft.

            https://www.eia.gov/dnav/ng/ng_pri_sum_dcu_nus_m.htm

            1,028 Btu per cf from:

            https://www.eia.gov/tools/faqs/faq.cfm?id=45&t=8

            1,028 BTU X 1,000 cubic ft = 1,028,000 BTU / thousand cubic ft.

            So for 17.1 million BTUs to match the Jack Pine, we’d need 16.6 thousand cubic ft

            16.6 thousand cubic ft X $12.60 / thousand cubic ft = $ 209.16 for the residential cost of the natural gas to math the heating value of the cord of wood.

            You would, of course, get a much better gas price that the $209.

            I’d figure $100 for a cord of the Jack Pine.

            The wood burning enterprise may have trouble turning a profit.

          2. I can buy split and seasoned hardwood for under $200/cord, but that’s neither here nor there.  The wood you’ll be using for bulk fuel isn’t logs, it’s sawdust, wood chips, shredded brush and so forth.  This stuff has almost zero value except as mulch and much of it presents a disposal problem.  If you can process it into e.g. pyrolysis oil, you convert it into a compact, reasonably storable and much more easily handled form.

            If it costs $20 to collect the material equivalent to 1 cord of jack pine (17.1 mmBTU) and the processing converts it to liquid with 60% of the energy remaining, you get 10.26 mmBTU for $20 or a shade under $2/mmBTU.  If you can gasify that liquid to clean syngas at 75% efficiency you get about 7 gallons’ worth of gasoline-equivalent for a bit over the price of a gallon of gasohol.  That’s not bad for something you’d otherwise probably leave to rot.

          3. “That’s not bad for something you’d otherwise probably leave to rot.”

            It seems to make sense. Perhaps a few bark burners (electrical generation) could help alleviate the potential problem that may occur with the planned coal plant closures. I believe smaller <20 MW plants are covered by different FERC and EPA rules so licensing could be easier.

            Without Federal subsidies, i don't think conversion to liquid fuels would be an option. the track record on cellulosic ethanol is not good.

          4. Perhaps a few bark burners

            Bark is a particularly bulky and difficult-to-handle fuel.  Transporting it will cost a great deal per ton-mile.

            i don’t think conversion to liquid fuels would be an option.

            Pyrolysis oil is sui generis; it is dense and made very easily from woody biomass (particularly torrefied biomass) but it is unstable, very acidic and has a high water content.  It isn’t suitable for conversion to petroleum-compatible motor fuels.  However, burning or gasifying it avoids most of the compatibility issues.  Once something is converted to syngas it doesn’t much matter what it came from.

            Converting woody waste to pyrolysis oil in the field allows it to be transported by tanker truck, far simpler and easier than dealing with bulk dry matter.  Spark-ignition engines have been run on gasified wood and charcoal for over a century.  Gasified pyrolysis oil presents no new problems and would allow the collection and transport system to operate petroleum-free.

          5. Bark burner above the bridge http://www.whitepineep.com/Lanse.html

            Which you’ll notice is right next to a great, big state forest.  Something else you might notice is that it is only 17.7 MW net, which is just a fraction of the power demand of the city of Houghton up the peninsula; all that area to provide fuel, and precious little to show for it compared to what people need.

            Put a NuScale 2-pack there in L’Anse and you’re talking.  You could use off-peak electricity to produce the pyrolysis oil (saving biochar as a carbon-sequestering soil amendment) and use the oil to co-fire your gas turbines for peaking and backup use.  Voila, carbon-negative power.

            J.H. Warden has been putting out about 10,000 MWh/month lately, or an average of about 14 MW.  This isn’t too bad, but if it has a heat-rate of 10,000 BTU/kWh and the wood yields 16 million BTU per short ton, it would require about 6300 tons per month or about 210 tons per day—several large semi-truck loads each and every day, to yield just 14 MW average.  This is clearly not something that can scale very well.

          6. I’ve met with the nice folks from White Pine/L’Anse/Traxys before. They are always looking for ways to keep the facilities running.

            I love the idea of SMR in Michigan’s upper peninsula!

          7. I’d love to have some NuScales at Big Rock Point.  One NuScale beneath Traverse City could light the whole city and environs, and heat the city with steam as well.  Imagine ice-free sidewalks and 3-season outdoor swimming pools.

  4. As I’m writing this, I’m cozy in front of my fire, (my sole source of heat) as it pours rain outside and yhe temp is in the high 40’s.

    Doing another remodel on the outskirts of Bakersfield, right where the urban sprawl tapers out and the almond groves begin. Last week, passing by a large grove, I noted a machine razing the trees, sawing them at the trunks. Within two days the entire grove was topped, laying in rows, just as they were felled. Two days later, passing by again, all that was left was a large flat field with two mountains of fine wood chips. Off to the biomass plant it goes, and the field will be replanted with whatever the farmer decides is profitable. Almonds were up this year, so I hsve no idea why this grove was razed. Perhaps the trees were past their prime producing years. The owner of the house I’m working on is an almond grower. I’ll have to remember to ask him. As I understand it, there are companies that raze these orchards with no cost to the farmer. I assume the chipped product is then sold to the biomass plant.

  5. Something I work very hard to always keep in mind is that a Good Idea is a Good Idea regardless of where it came from and that something which is a Bad Idea 90% of the time can still be a Good Idea the other 10%.

    This is why if you were to poke about the bookcase in my living room you’d find things like Mycelium Running next to The Answer next to Rainwater Harvesting for Drylands and Beyond and so on so forth. In each case I might only agree with a fraction of what the author has to say and find them otherwise anywhere from comically deluded to dangerously misguided but still, Good Ideas are Good Ideas.

    I’m going to go a little into the weeds here, bear with me as this does come back to biomass.

    Recently I’ve been reading about improvements that could be made to agriculture. Now don’t get me wrong, modern agriculture is an amazing thing that provides massive amounts of food reliably and cheaply. But it’s not without problems: plowing causes us to lose topsoil to erosion faster than it’s created, surplus fertilizer runoff creates dead zones, giant mono-culture fields are crappy places for biodiversity.

    What’s come to my attention is the work of a place called Badgersett Farm. They’ve got a little bit of woo going on with ‘GMOs are bad!’ and all of that nonsense, but as mentioned before recognizing something of value doesn’t require 100% agreement. What they advocate for and are working on is using perennial woody plants for growing staple crops. Their work so far has mostly focused on hazelnuts and chestnuts, with the line of hazels they’ve been breeding the most advanced and closest to ‘prime time’.

    This idea has numerous benefits, perennial plants are potentially much more productive than annuals, not plowing and replanting each season saves the topsoil, no fertilizer runoff as there’s no bare soil for it to wash out of along with plenty of plant roots to take up the excess, increased biodiversity in the cropfield, and finally when the plants grow too large they may be cut down to the ground allowing them to re-sprout from the root crowns and generating a significant amount of wood biomass in the process.

    What do we do with this wood? I’m not suggesting we go and use it to fuel a power plant, there’s a better use for it. Even once the energy supply of the planet has been decarbonized there will still be an excess of CO2 in the atmosphere that needs to be removed.

    So what I’m suggesting be done is pryolize the periodic wood harvest into charcoal and plow it back into the fields as biochar. This would both sequester the carbon out of the atmosphere long term AND further increase the fertility of our agricultural lands.

    When wood is heated in a sealed container it emits flammable gas, so once started the charcoal kiln would require no outside source of fuel. If done in conjunction with the perennial crops we wouldn’t be turning virgin land into biofuel plantations. Likewise this also wouldn’t require chopping down forests and shipping wood about. There’s no reason the charcoal kilns couldn’t be spread about in agricultural areas so relatively little effort would be needed to bring the wood to the kiln, put it through the pyrolysis process, and return it to local fields.

    So yeah, one use of biomass that’s no a giant ecological boondoggle and would show real benefits.

  6. If you are talking biomass, you are talking about corn. The rest is irrelevant. We are burning 40% or our corn crop now if I remember correctly. It is a scandal. Land should be left for food crops or natural settings. We can get all the energy we need from nuclear, without dispoiling the environment, or putting poor people in competition for food with affluent car-driving Westerners.