Let’s face it,
we are all power pigs. We love our electric
appliances and cars. Who among us does
not appreciate jetting to far-off lands?
Then of course, there is the comfort of air conditioners and furnaces
that keep our homes and offices at the perfect temperature. The problem is that all these seemingly
indispensible conveniences have been produced with fossil fuels that are the sources
of greenhouse culprits leading to global warming.
The amount of
carbon dioxide produced when a fossil fuel is burned is a function of the
carbon content of the fuel. True enough,
as shown in the table below, not all fuels are created equal.
Fuel Source
|
Pounds of Carbon
per Million Btu
|
Coal, anthracite
|
228.6
|
Coal, bituminous
|
205.7
|
Diesel fuel
|
161.3
|
Gasoline
|
157.2
|
Propane
|
139.0
|
Natural gas
|
117.0
|
Source: U.S.
Energy Information Administration
|
Of course, the
table above shows only the carbon emissions from actually burning the
fuel. If the original production process
is also taken into consideration, i.e. the lifecycle of the fuel source, then
carbon emissions for every source would be higher. It is also valuable to see the conventional
fossil fuel sources alongside renewable energy sources, as shown in the table
below.
Power Source
|
Gram Carbon Dioxide per Kilowatt Hour
|
Coal, all types
|
910
|
Natural gas
|
650
|
Biomass, dedicated
|
420
|
Solar, photovoltaic
|
180
|
Nuclear
|
110
|
Geothermal
|
79
|
Solar, concentrating
|
63
|
Wind
|
56
|
Hydropower
|
24
|
Source: National
Renewable Energy Laboratory, Intergovernmental Panel on Climate Change
|
The data in the
second table makes it clear that shifting our power generation and
transportation fuels to renewable sources reduces but does not eliminate carbon
dioxide emissions. True enough the conversion
of electricity generation from a coal-fired power plant to hydropower, as an
example, leads to a 97% reduction in greenhouse gas emissions. That is a powerful change.
There are some
technologies and process tweaks that can deliver at least partial redemption
for the fossil fuels. For example,
coupled with carbon capture and storage, the lifecycle greenhouse gas emissions
from natural gas can be reduced to as low as 245 grams of carbon dioxide per
kilowatt hour from 650. That puts
natural gas much closer to the emissions neighborhood where we find photovoltaic
systems and well below biomass fuel sources for power generation.
Additionally,
there are some technologies under development that may be able to redeem
coal. One possibility is the use of
pulverized or powdered coal blown into the firebox at coal-fire powered plants. This would lead to far more efficient use of
the furnace capacity and reduce the amount of coal that has to be burned for
the same power generation. Using
pulverized coal could reduce greenhouse gas emissions to 250 grams per kilowatt
hour. However, integrating a high pressure
gasifier into a coal-fired power plant could lead to even better results. First the coal is converted to synthetic
gas. Impurities such as sulfur and
mercury are removed and turned into commercially valuable by-products. With sequestration of any remaining carbon
dioxide such plants could have a lifecycle greenhouse gas emission level of 230
grams per kilowatt hour.
The next few
posts will look at the companies developing technologies that could lead to
environmental redemption for some of these carbon culprits.
Neither the author of the Small Cap Strategist web
log, Crystal Equity Research nor its affiliates have a beneficial interest in
the companies mentioned herein.
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