[Gasification] Charcoal Gasifier No 2.

[Energies Naturals]

Ken,

urban heating systems work all on low temp. heat, mostly well below 70 
ºC.There is no need to gasify  biomass to achieve that.
This is a case for pellets/chips/log-burners . Modern furnaces have 
excellent smoke test results and are above 90% eff.
Even small 10 kW pellet furnaces (water) in your living room get this and 
you can see the fire and they cost 3000,- (?
Totally automatic and regulated.Plug and play. (This is a good example of 
where gazzies have to look.)
No harm from these and legislation will take care of the smoke problem.

Rolf
----- Original Message ----- 
From: "Ken Boak" <kenboak at stirlingservice.freeserve.co.uk>
To: "Discussion of biomass pyrolysis and gasification" 
<gasification at listserv.repp.org>
Sent: Friday, July 27, 2007 9:49 AM
Subject: Re: [Gasification] Charcoal Gasifier No 2.


> Bob & List,
>
> The first part of this is OFF TOPIC - but please bear with me.  It is a
> classic example of what can happen when renewable energy products are sold
> in retail outlets.
>
> Small windturbines in the <1000W rating enjoyed a brief commercial hype in
> the UK, but were quickly deemed unfit for purpose.  This mirrored the same
> series of events which happened in the US a few years previously.
>
> The main reason is that they required considerably more wind speed than 
> was
> available in most urban areas, and their average output was often about
> 1/8th of that quoted - because the mean wind speed was half of that quoted
> by official figures.
>
> Addditionally the grid tied inverter supplied with the turbine had an
> overhead net draw of about 50kWh per year from the grid to power its
> internal electronics, interlocks etc.
>
> As a result, many were finding that their $3000 roof mounted turbines were
> underperforming considerably and even costing them electricity.  This
> situation has led to a knock-on effect of low consumer confidence in
> windpower.
>
> Renewable energy schemes tend to work better when you have the economy of
> scale,  i.e large wind farms,  large solar arrays in the dessert, large
> hydroelectric projects.  The same is probably true for gasification
> schemes - likely these need to exceed 1MW in capacity before they can be
> viable commercially.
>
> The idea of a 10MW gasification plant that burns municipal waste,
> construction waste, tree surgery prunings etc and supports 10,000 houses 
> is
> probably the minimum size that would be viable.
>
> There are lessons to be learned from the past - Britain was once almost
> exclusively heated by coal fires, and all household waste was put on the
> fire.  10 million individual coal fires in the high density populated 
> areas
> gave rise to a lot of atmospheric pollution and associated respiratory
> diseases.
>
> Now Britain is extensively heated by gas, and these polllution problems 
> have
> been vastly reduced,  However, recent hikes in gas prices have motivated 
> the
> UK to purchase woodstoves, often Chinese manufactured and often badly
> installed resulting in greater levels of urban smoke levels.  Might not a
> return by individuals to using gasifying wood fired boilers, might lead to
> additional airpollution with tars and other carcinogens?
>
> We should also not forget the historical situation in China, when in Mao's
> attempt to boost steel production, his administration encouraged the use 
> of
> "backyard blast furnaces".  Very little usable steel was produced but
> millions of rural poor faced starvation.
>
>
>
> Ken
>
>
>
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