I hope no one was suggesting that biochar could enable a business-as- usual scenario of fossil-fuel use. That would undermine credibility a lot worse than anything from the anti-biochar side. It doesn't pass the sniff test to say that we're going to spend a bunch of energy hauling coal out of the ground and simultaneously offset it all by putting charcoal into the ground.
The need to switch to renewables isn't a matter of serious debate, as far as I'm aware. For most of the energy, no matter whether the source is wind or sunlight or waves or whatever, that means it will arrive as electricity. But there will always, for as far ahead as I can see, be some need for hydrocarbon or alcohol fuel in applications where energy density is especially valuable. (Maybe eventually there will be super-duper-capacitors, or quantum flywheels, or rectennas getting energy beamed from solar power satellites, or who knows what. But developments in the pipeline look like batteries and wires to get most energy to where it's used.) And hydrocarbons will be needed for chemical-industry feedstock for everything from coffee cups to motor oil. So "very promising" means that a decent range of specialty applications may get their fuel/feedstock from pyrolysis with part of the cost being covered by the agricultural and geoengineering value of the biochar byproduct. On Apr 14, 9:54 pm, Ken Caldeira <[email protected]> wrote: > Folks, > > I think biochar suffers from the same fate as most biomass options. > > Because of the low efficiency with which ecosystems convert sunlight to > reduced carbon and because only a fraction of this reduced carbon will be > converted to biochar, biochar options are unlikely to be able to offset more > than 1 W of fossil-fuel CO2 emissions per square meter of land area. My > post-doc has done some calculations indicating that this estimate might be a > factor of 5 too small (taking into account other inputs and inefficiencies). > > We in the United States each use about 10 kW of energy, so this would be on > the order of a hectare per person at the higher efficiency, 5 hectares at > the lower efficiency. > > For 7 billion people at 2 kW, this is 1.4 x 10^13 m2, or roughly 10% of land > area on Earth at the higher efficiency -- roughly the amount of land already > devoted to agriculture -- or half the land area on Earth if my post-doc is > right about the lower efficiency. > > So, this is another one of those things that could be good to do where > appropriate, but is not likely to be a major player in the grand scheme of > things. > > Best, > > Ken > > ___________________________________________________ > Ken Caldeira > > Carnegie Institution Dept of Global Ecology > 260 Panama Street, Stanford, CA 94305 USA > > [email protected]; > [email protected]http://dge.stanford.edu/DGE/CIWDGE/labs/caldeiralab > +1 650 704 7212; fax: +1 650 462 5968 > > On Tue, Apr 14, 2009 at 6:24 PM, dsw_s <[email protected]> wrote: > > > I don't get the impression that the anti-biochar pdf is very > > credible. For example, it suggests that there's basically no degraded > > land in the world, that could be improved with biochar. It's a big > > world. There's a lot of not-so-degraded land, and a lot of degraded > > land. It wouldn't surprise me if the loudest claims over the last > > couple decades were grossly exaggerated as to how much biological > > productivity was being lost as vast areas of the Amazon got clear-cut, > > eroded, and turned into quasi-desert. But to dismiss biochar out of > > hand for lack of land to improve with it (even if it works, which they > > reject, and even if it's affordable, which they reject, and so on) > > just sounds as though they're looking for anything that would > > invalidate biochar and then reasoning backward to the putative facts. > > It may be that the improvable acreage is enough only for X gigatons of > > carbon to have any benefit, with X too small to be a big part of the > > overall picture. It would still be able to generate legitimate carbon > > credits up to that point. > > > On Apr 14, 9:58 am, Ray Taylor <[email protected]> wrote: > > > I thought we should rename this biochar for the sake of the archive. > > > > Does biochar hold water significantly better than the organic matter > > > it was made from? Especially if the latter was used as mulch? > > > > [See YouTube "Greening the Desert" - clip from permaculture > > > institute of Australia] > > > > Thank you all for bringing biochar to my attention. I like the > > > fact that (for Africa) it can be locally produced in low-tech kilns. > > > > I'd be interested to know if there is a site which replies to the > > > following limitations/drawbacks: > > > >http://www.biofuelwatch.org.uk/docs/biocharbriefing.pdf > > > > Raywww.globalcoolers.net > > > > On Apr 14, 3:20 am, David Schnare <[email protected]> wrote: > > > > > My Center is doing a major report on putting carbon back into the soil > > as > > > > the means to developing two kinds of market mechanisms for farmers, > > > > nutrients and carbon. I'll keep the group informed as we prepare our > > > > materials, but just to give you a heads up, this is no silver bullet > > (for > > > > carbon). Biochar is better than crop detritus (no till farming), but > > both > > > > lose carbon due to microbial action (CO2 emissions). However, both do > > a > > > > terrific job creating a substrate for water. They take high clay soils > > and > > > > turn them into an organic sponge, holding nutrients in the ground, > > attached > > > > to the invested carbon. > > > > > David Schnare. > > > > > On Mon, Apr 13, 2009 at 10:03 PM, dsw_s <[email protected]> wrote: > > > > > > Wow, that sounds very promising, although we'll have to see about the > > > > > economics. > > > > > > I hadn't heard (or hadn't absorbed) that the biochar was to come from > > > > > a pyrolysis process that makes oil and gas, so there's more > > > > > hydrocarbon and less just-plain-carbon than there would be in > > charcoal > > > > > from burning in open air. I don't know how stable regular charcoal > > is > > > > > either, although it sounds as though it's much more stable than I had > > > > > thought. I would certainly expect biochar or ordinary charcoal to > > > > > improve water retention (at least in most soils), and one of the > > > > > references in the Wikipedia biochar article says it does (without > > > > > saying for what kinds of soil, as far as I saw). > > > > > > I hope we study soil ecology before doing it on a very large scale, > > > > > though. > > > > > > On Apr 12, 5:18 am, Andrew Lockley <[email protected]> wrote: > > > > > > Biochar is highly stable in soils, and lasts centuries-millennia as > > Terra > > > > > > Preta. > > >http://en.wikipedia.org/wiki/Biocharhttp://en.wikipedia.org/wiki/Terr... > > > > > > I understand it also bulks up the soil, trapping '3rd party' > > carbon. > > > > > > > I am unsure whether this either affects the hydrological properties > > of > > > > > the > > > > > > soil, or promotes forest regrowth. If either were the case, it > > could > > > > > have > > > > > > the cloud-inducing effects discussed. This effect could be highly > > > > > > significant and I hope someone expert can consider it. > > > > > > > A > > > > > > > 2009/4/12 dsw_s <[email protected]> > > > > > > > > But wouldn't the carbon in the biochar get returned to the > > atmosphere > > > > > > > fairly quickly if it were used that way? > > > > > > > > On Apr 11, 6:24 pm, Andrew Lockley <[email protected]> > > wrote: > > > > > > > > It would be very interesting to see if biochar has a similar > > effect. > > > > > If > > > > > > > > biochar could lock up carbon in soils, thicken soils, preserve > > and > > > > > spread > > > > > > > > forests and brighten clouds it would have benefits that could > > > > > reasonably > > > > > > > be > > > > > > > > described as 'ginormous'. > > > > > > > > I'd be interested to know if anyone in this group could explore > > these > > > > > > > > effects and potentially look at doing a paper or a model run on > > them. > > > > > > > > > A > > > > > > > > > 2009/4/10 dsw_s <[email protected]> > > > > > > > > > > That sounds a lot like how I imagine geoengineering can work. > > A > > > > > > > > > suggestion I've made is that materials like expanded > > vermiculite > > > > > and > > > > > > > > > perlite (basically rock popcorn) could be used to increase > > water > > > > > > > > > retention in soil for both agricultural and climatic benefit. > > The > > > > > > > > > climate benefit includes CO2 removal by weathering, but the > > > > > > > > > distribution could also be chosen to optimize cloud patterns. > > > > > > > > > > On Apr 9, 11:50 am, Ray Taylor <[email protected]> wrote: > > > > > > > > > > Hello all, > > > > > > > > > > > I've been in consultation with a range of land-atmosphere > > > > > > > > > > and cloud meteorologists, looking at scope for increasing > > > > > > > > > > stratus and cumulo-nimbus over land in regions identified > > > > > > > > > > in GLACE (nasa). > > > > > > > > > > > Literature review available atwww.globalcoolers.net > > > > > > > > > > > Focus is on West Africa and rainwater harvesting, > > > > > > > > > > pilot studies plus 4 continents alliance-building. > > > > > > > > > > > Anyone interested in collaborating? > > > > > > > > > > > Ray Taylor > > > > > > > > > > > ray [at] andy-taylor.org > > > > > -- > > > > David W. 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