Bit article about it in the Times today, too.
And a lament on BBCR4Today yesterday morning about how many studies in
the biotech area are not reproducible - meaning that any results they
purport to give are worthless.
The reasons range from peer pressure, pressure on journals to be at the
cutting edge, "tidying up" of data, pressure on funding bodies to be
seen to be getting results - all the usual rubbish which we have seen
elsewhere (can't for the life of me think where though, at the minute).
HAL 9000: Dave. Put down those Windows disks. Dave. DAVE!
but is the problem one that it doesn't work in principle
or merely because we are burning stuff that has come from too far away and
has caused more pollution being transported than we are saving
but then we have to add in the "cost" of transportation for the alternative
fuels that we would have used
I've not read the papers line by line, but AIUI the argument is that
felling and shredding actual trees for biomass fuel, as opposed to
using just saw-mill waste and trimmings, increases the CO2 content of
the atmosphere in the short term, while re-growth only reduces it in
the long term. It takes only a few weeks/months to fell a tree, shred
it and burn it, whereas it can take many decades, possibly centuries,
to re-grow a tree of the same size.
Shreddings and saw-mill waste left to rot on the forest floor produce
CO2 over a timescale comparable to that for combustion, so don't
contribute to atmospheric CO2 over a different time-scale to burning.
Each of the two links I gave has in turn a link to a PDF of the actual
papers, near the bottoms of the respective pages.
http://tinyurl.com/joukm5v and http://tinyurl.com/zf9ltrw
Possibly, but I associate methane production with anaerobic
decomposition, for example inside peat bogs or in the bottom of
stagnant ponds (see marsh gas https://en.wikipedia.org/wiki/Marsh_gas
). Shreddings left to rot in the open air wouldn't produce much, I
don't think, but I may be wrong.
In the short term methane is a worse GHG but in an oxygen rich
atmosphere it has a relatively short half life before it becomes CO2.
I agree that it makes sense to burn saw mill waste locally, but not to
plant and chop down forests ship them half way round the world to meet
some renewable target obsession. Wood is just not energy dense enough!
Absolutely not. Coal is much more energy dense than wood pellets, so
you get far more coal per shipload than you get for wood pellets. Or
putting it another way, you need more shiploads of wood pellets than
coal to get the same amount of energy, shit-fer-brains.
Coal import data for 2015 from here: http://tinyurl.com/zkmarrr
(annual tab and types of coal summed)
European Union 614
Republic of South Africa 317
Other countries 427
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