Page 13 - Handbook of Energy Engineering Calculations

pollution during their manufacturing process. This fact is pointed to by
environmentalists as a negative fact to be held against the “clean” or “green”
method of power generation.
The intense worldwide interest in greenhouse gases, atmospheric pollution,
and global warming started a new vocabulary in the energy engineering field.

Today we encounter terms such as “green” power, “clean” power, carbon
footprint, carbon taxes, energy taxes, biofuel usage, caps on power-plant
carbon dioxide emissions, energy audits, etc. Most these terms imply greater

costs in generating power because of emissions reduction requirements. This
handbook recognizes the new demands on energy-system engineers and
designers and includes calculations that help the resulting design comply with
modern global-warming-reduction requirements.
To reflect modem design conditions, this handbook starts with calculations

of external combustion of fossil fuels used in steam power plants because this
is the widest used (some 70 percent of the total in many areas) form of
electric energy generation today. Next, the handbook presents gasturbine

calculations. Today, gas turbines are the favored motive power choice for
steam-station expansion and topping services. With its small footprint,
freedom from complex regulations, and use of low-emissions natural gas, the
gas turbine is becoming more popular in energy engineering every year. Also,
using heat-recovery steam generators (HRSG) in the exhaust of a gas turbine

allows significant heat recovery while improving the overall cycle efficiency.
Internal-combustion engines—the diesel, natural-gas reciprocating engine,
and other such power generators—comprise the Section 4 of the handbook.

The diesel is a popular form of electric-power generator in rural areas around
the world. And its carbon footprint is not as damaging as that of the
traditional steam plant.
Natural-gas-powered reciprocating engines are popular in oil refineries and
in areas having abundant supplies of natural gas. In some areas these engines

can be run on either natural gas or diesel fuel, depending on which is cheaper.
Cogeneration, wherein waste heat is put to work to improve the overall
cycle efficiency, and to wrest more energy from a given process, is popular

with steam turbines, gas turbines, and internal-combustion engines. Since
greenhouse gases can be reduced when fuel consumption is lowered,
cogeneration is an important step in conserving, and reducing, fossil-fuel
usage. This handbook presents a number of cogeneration calculations that can