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A CHP machine is
just a fossil fuel powered electricity generating machine
that recycles the wasted heat as warmth for your home. So
far many of these machines have been tried out across the
land but normally in large commercial buildings or community
housing projects. It really hasn't scaled down as far as
being generally applicable inside someone's house. However,
domestic boiler sized machines have been developed and are
being trialed.
What does this
all mean? Well, you will still get some of your power from
the main grid supply. However, when you need hot water or
space heating you switch on your CHP box and whirs into life
generating the electricity for your house. If you don't use
all the electricity it generates then you can sell it back to
the grid. Whist electricity comes out of the box for your
lights and TV a lot of heat comes out too and this is used
to heat your home. Waste not, want not. Efficiencies of 80%
are claimed although, with the advance of the condensing
boiler, these figures are only slightly better than
conventional technology. What is more, rumour has it that
trials of domestic CHP have not proven that successful.
Besides, have
you ever seen a CHP machine for sale? No? Neither have we.
Although the enthusiasts would like to use them there simply
are none available to the domestic market at time of
writing. This could change but fitting CHP will still be
quite low down on your list of priorities when Ground Heat
Pumps and Solar Thermal are so well established and easily
obtainable.
Hence much of
the interest in CHP has moved back to where it started - in
district heating systems where a community shares a single
heating system. There is also far less emphasis on using
such systems with fossil fuels. Now the talk is all of
Biomass CHP. Large plant is more efficient that small plant
so there are some economies of scale if many homes club
together for such a system. It is much the same story for
community wind turbines featured elsewhere on this web site.
In the UK alone
it is expected that CHP could contribute 103 TWH of heat and
34 TWH of electricity from biomass. We can also burn waste
materials with an energy equivalent of 5 million tonnes of
coal annually. Burning this would mark a remarkable
reversal in fortune for the solid matter burner in our
communities. Recoverable heat from waste could contribute 22
TWh of heat and 7 TWh of electricity in the UK. There are two
other words we will need to research. These are
"gasification" and "pyrolysis". Pyrolysis of 400,000 tonnes
of used car tyres can deliver 2.4 TWh of energy through an
80% efficient CHP process.
So the
technology is here to stay, although there is probably
nothing the average Carbon-Cutter can do about it as an
individual. Doing things as a community represents a
sea-change in the way social policy has drifted over the
last 100 years. As such it means a revolution in the very
meaning of the word "community". Are we ready? |
