Think about the way you would typically extract energy from wood. You'd
burn it, just like you might burn coal or oil or natural gas. The
stored energy in the wood is chemical energy, meaning that it can be
released by a chemical reaction (burning). It's closely related to
those fossil fuel energies, because the chemical energy was formed by
photosynthesis, using energy from sunlight as the input.
This business of giving names to all sorts of different energies
can get pretty silly sometimes, because you can call the same energy
all sorts of different names. We've discused that in other answers.
Mike W.
There are some other small ways wood can store energy -- the big
one is the chemical energy. You could just heat up the wood, and then
it would have some heat energy (we prefer to call it heat energy rather
than wood energy because there isn't anything special about the wood
here). You could also flex the wood and it would store energy like a
spring does. A bow and arrow work by storing energy in a wooden (well,
okay, most are made out of fiberglass these days, but they used to be
made of wood) bow which can be relased at a rate which is much quicker
than it was put in. The wooden arrow (these too are fiberglass today)
has kinetic energy as it flies. A wooden musical instrument has both
kinetic and potential energy (similar to a spring's potential energy)
as it vibrates. You probably don't want to worry about all of these
other things, since there isn't nearly as much energy in these as there
is chemical energy which you can transform into heat by burning the
wood.
Tom
(published on 10/22/2007)
