The Rural Voice, 2002-10, Page 24r` Electrkclty Co-Generat,on
El
Electricity from
manure
Turning liquid manure into
electrical power could come sooner
than you think
By Keith Roulston
Jmagine
if that tank full of liquid
manure behind your barn could
become a new profit centre for
your farm, creating electricity for
sale onto the provincial power grid,
yet still remaining a valuable
fertilizer for your crops but without
worry about hazardous bacteria.
It sounds like a pipe dream? Well
for now it is but this dream could
become a reality for some Ontario
farms within months or years.
The dream was outlined at
Canada's Outdoor Farm Show by
Bill Jones, a senior engineer with
Kinetrics, "one of the bits and
pieces" that came out of the
restructuring of Ontario Hydro. One
of the company's many jobs is
exploring alternative energy
resources from solar to biomass.
Selling electricity to the grid isn't
economical at the moment, Jones
admitted, but the day may fast be
approaching when it will. What may
be more economical, currently, is
replacement of your own electrical
needs by on-farm generation.
The breakup of Ontario Hydro has
also created an opportunity in the
market place for people to generate
electricity and sell it into the spot
20 THE RURAL VOICE
market on the Hydro One grid, Jones
says, though the red -tape is still such
that it will be difficult for some time
to come.
"When you get down to delivering
power to the grid there are
regulations that are required there,
(and) there's the price to provide the
equipment that you need — at the
moment I think it's safe to say it's
not like falling off a log, it's not the
kind of thing that's easy to do."
More viable at the moment is
generating electricity to meet the
needs of your own electricity
operation and reducing your
electricity bills.
The key to the possibility for
farmers with liquid manure is the use
of an anaerobic digester that
promotes the breakdown of manure
without the presence of oxygen,
creating methane gas. The gas is
captured by the digester system and
can be burned in an engine which can
drive an electrical generator.
(Producers of dry poultry manure can
actually pellet the manure and burn it
to power a boiler to create the steam
to drive a turbine and create
electricity.)
In a digester, the liquid manure
Engineer Bill Jones of Kinetrics
(lower left) explains the process
used to create methane gas from
manure and use the gas to
generate electricity, as shown in
the diagram at the left.
stays in a container with the air
sealed out of it for most of a month,
Jones explained. The methane can '
not only be used to power a motor to
generate electricity but can be burned
to heat water for whatever hot water
uses your farm may have.
Because the digester is a sealed
container, there is no smell from the
manure.
A small unit producing up to 50
kilowatts is likely to match the power
you require on your farm, Joi.' s says.
By replacing electricity bought off
the grid you are basically saving the
retail price of electricity, the best rate
of return you can expect.
The benefit for farmers is that
when the manure has gone through
the digester, it is still a valuable
fertilizer.
"This whole process is dealing
with an environmental difficulty in a
very good way," Jones says. "After
the digestion process is done you
h.ve a very good fertilizer. One of
the neat things about it it, because it's
done at a very high temperature
towards the end of the process, 99
per cent of the pathogens like E. coli
have been killed."
In fact by controlling the digestive
process the operator of the digester
can alter the proportion of nitrogen
and phosphorous in the fertilizer left
after the digestion process.
At the same time there is waste
heat that can be used for on-farm
needs.
What may develop down the way,
Jones suggests, might be co-ops
where a group of farmers gets serious
about turning their manure into a
profit source by selling electricity.
By pooling their liquid manure
together and building a larger
digester, they could take advantage
of economies of scale, producing up
to one megawatt of power (by
comparison one unit at the Pickering
nuclear plant produces 750
megawatts). On this scale it helps
farmers deal with the regulations of
dealing with the safe generation of
electricity for the grid. The meter to