I'm not trying to disagree with your concerns Dan; in fact I share them.
Admittedly, my previous post was a little sloppy and a bit hurried so I'll try
again to better communicate my thoughts.
I agree with you completely that we need to do a better job of how we use
energy on the consumption side through conservation and energy efficiency. On
the demand side, conservation means using less by going without (turning off
the lights or turning down the thermostat) and efficiency means using less
through more efficient appliances such as Energy Star rated refrigerators.
While we need to do this, it does not mean that we should not aim to make our
energy production more efficient as well, which is what distributed generation
accomplishes, thereby drastically reducing pollutant emissions. To illustrate
this, a traditional centralized large plant such as the Black Dog coal plant in
Burnsville or the Prairie Island nuclear facility in Red Wing run at efficiency
factors of about 30%. This means that the electricity that reaches consumers
from these plants only represents 30% of the energy that started in the coal or
the uranium. Around 70% of the energy in this scenario is lost through the
combination of the process necessary to generate steam to turn turbines (this
is the waste heat) and the fact that transmission lines lose electricity over
distance. The result is that more coal is burned which gives off more CO2,
more SOX, more NOX and more mercury. On top of this, in the winter time, all
of the customers served by the Black Dog coal plant have to heat their homes
and businesses resulting in natural gas being burned (and more CO2) or more
electricity needed to be generated (more coal being burned).
Compared to the above model, a typical CHP plant comes with an efficiency
factor of about 70 to 80%. This improved efficiency is accomplished by using
the waste heat from electricity generation to heat buildings in the winter
(taking away their heating energy requirements and resultant emissions) and by
saving electricity lost in transmission because the distance over which it is
transmitted is much, much shorter. What my last post neglected to mention is
that the waste heat in a CHP plant can also easily be used to cool buildings in
the summer eliminating their added cooling energy needs and the resultant
emissions.
My analysis says that if this project has strict restrictions on what can and
can't be used for fuel and it is required to use the best pollution control
technology available then it would be a net benefit to our neighborhoods and
our natural environment. The Green Institute originally proposed this project
and as far as I know the only things that have changed are the ownership model
(which can easily be criticized, I agree) and the analysis that says there
won't be enough biomass fuel over the long term. I don't think that the Green
Institute ever took the position that a CHP operation, even one fueled by
burning biomass, is a bad idea in general for environmental reasons. I meant
to ask my friend Diana at the Green Institute about this when I saw her last
week, but didn't get the chance.
Lastly, I'd like to share some thoughts on fuel. A hypothetical CHP plant in
Midtown could run on many different fuels. My preferred scenario is that it is
ultimately run on green hydrogen generated from our abundant wind and solar
resources in the Upper Midwest. We have vast wind and solar resources in our
region that are not being utilized. A CHP plant could either be powered by a
green hydrogen fired turbine (much like the retrofitted High Bridge plant in
St. Paul and the Riverside plant in MPLS, but with hydrogen rather than natural
gas for fuel) or a regenerative fuel cell system. The fuel cell system results
in zero harmful emissions while the hydrogen combustion system results only in
NOX. In the meantime, if the toxins can be kept from our neighborhoods (they
seem to be able to accomplish this with similar projects in Copenhagen and
Amsterdam) and an acceptable fuel supply can be secured we should work to make
this happen. Add my idea of using CO2 emissions in an urban greenhouse system
to produce local produce (and more jobs) and this project would become a slam
dunk--even if its impact were only as a demonstration. (Sorry for the sports
metaphor.) Imagine a transit-oriented redevelopment of the sadly suburbanized
Lake Street and Hiawatha intersection with a network of urban greenhouses on
the top of higher density, mixed-used buildings producing a sustainable local
food source, added tax base, and other benefits year round in Minneapolis.
Hmmmmmmmmm. . .
I'm certainly not an expert on the availability of biomass fuel and will leave
that to others to hash out. If a biomass fuel supply can be secured for a long
enough period to allow for the plant to be upgraded to a green-hydrogen powered
system in the near future (less than 10 years) than this hypothetical CHP plant
would be the shining example of clean energy in the entire country.
Thanks for reading,
Matty Lang,
Midtown Phillips