We Have Met the Future and It Is Green - Sustainable Design: The Science of Sustainability and Green Engineering - page 309

Figure 8.2 Power generation of
cycling for a general population of
healthy adults and competitive
athletes compared to extinction
(fatigue).

8

7

6

First-Class
Athletes

5

Healthy
Humans

4

3

2

1

0

0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.5

Sustained level of power to the pedals (hp)

In a similar search for a more environmentally friendly source of fuel for a
college campus, junior electrical engineering major Kamaal's innovation proposal
sought to replace the traditional source of coal for firing the central steam plant
on campus. Kamaal's “Green Steam” innovation resulted from an examination
of the current coal-fired boilers and a study of the upgrades to the system since
its original installation, aimed at improving performance efficiency. In her study
of the environmental impacts of the current system, Kamaal identified several
concerns, including:

Particulate matter from incomplete combustion in the form of bottom ash
and fly ash
Sulfur dioxide emitted in a gaseous form, which contributes to respiratory
illness, visibility impairment, acid rain, and the potential for altering the pH
of soil and water
Nitric oxide emitted, which contributes to global warming as a greenhouse
gas and is also a respiratory irritant
Carbon monoxide emissions, which depending on the fuel oxidation effi-
ciency of the coal and the combustion process, can in high concentrations
cause human sickness and is also a greenhouse gas
Other volatile or semivolatile organic compounds formed as products of
incomplete combustion