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Hi John, Rick & All, Nov 18, 2012
A source that permits a rough estimate of extraction area is
http://www.gov.ns.ca/natr/forestry/reports/ai_tables2.pdf
Based on total gross growth in Table 1, the province-wide average annual
increment is ~3 m^3/ha. Assuming specific gravity of green wood to be 2/3,
the annual growth increment is then 2 metric tonnes/ha.
This power plant, that consumes 200,000 T/yr, would therefore use the
annual increment from 100,000 ha= 1000 km^2 or an area of woodland 40 km x
25 km.
The NS Atlas maps are each about 40 x 25 km and there are 90 of these.
Divide by half to allow for the low wood increment at sea= 45 units.
Set aside 2/3 for farmland, roads, power lines, urban area, barrens etc.
still leaves 15 units.
So, as back of envelope estimate (a small envelope), woodland in the
province could feed about 15 such biomass plants.
Not that I am a great fan of the biomass plant in question but this
megaproject approach is the predictable outcome of government mandated
targets. Use of biomass, including forest biomass for energy is, in my
view, highly desirable provided it is done with regard for environmental
considerations and energy use efficiency.
To imply that biomass burning contributes "...to global warming" is just
BS. It can contribute if you haul wood from the far end of the province to
feed this plant and it must contribute some (unless you use biomass to power
the harvesting and hauling equipment) but such contributions are dwarfed by
outright burning of fossil fuels for energy.
Logically, biomass plants should be small enough to be fed by local
supplies (the meaning of local being an engineering balance) and located
where use can be made of the waste heat for e.g. residential/industrial
heating, greenhouse heating, culturing algae for fuel...
To suppose that biomass for energy should be dried along the lines of
firewood is comparing apples and oranges and it is not necessary to air dry
firewood for one year let alone two. For a high value product like firewood
it is practical to cut it into short lengths for drying, split to speed
drying and stack preferably sheltered from rain & snow. If the drying is not
sufficiently rapid, especially for Poplar, Birch, live Spruce and live Fir,
then appreciable carbon is lost to fungal/bacterial action (and I suspect
even by autolysis). Biomass wood would likely be chipped for ease of
mechanical handling and consequently would not dry readily. Drying in long
or short lengths and then chipping would consume much more energy than would
chipping green wood so burning green chips is likely the practical approach.
Yt, Dave Webster, Kentville
----- Original Message -----
From: "John and Nhung" <nhungjohn@eastlink.ca>
To: <naturens@chebucto.ns.ca>
Sent: Sunday, November 18, 2012 8:19 AM
Subject: RE: [NatureNS] "Burning our forests: large-scale vandalism"
> Yup. I do wonder if and how they will find a sustainable source of fuel
> for
> that plant.
>
> -----Original Message-----
> From: naturens-owner@chebucto.ns.ca [mailto:naturens-owner@chebucto.ns.ca]
> On Behalf Of Rick Whitman
> Sent: November-18-12 7:24 AM
> To: naturens
> Subject: [NatureNS] "Burning our forests: large-scale vandalism"
>
> A strong article in yesterday's C-H on the biomass issue:
>
> http://thechronicleherald.ca/opinion/178080-burning-our-forests-large-scale-
> vandalism
>
> Rick Whitman
>
>
> -----
> No virus found in this message.
> Checked by AVG - www.avg.com
> Version: 2013.0.2793 / Virus Database: 2629/5902 - Release Date: 11/17/12
>
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