Environmental Engineering Reference
In-Depth Information
enclosed fields, open-cast mines several kilometres in diameter, and the first urban sprawl
would have been visible. Since then, humankind's topographical footprint has deepened
and broadened. Today more than 30 per cent of the Earth's land surface is appropriated for
Land Impacts
The impacts of energy use on land may be grouped into three categories. The first involves
the least impact and includes coal, natural gas, and nuclear power, through the extraction
of highly concentrated resources and their conversion to energy or more refined fuels in
power plants or refineries. Of the alternative energy resources, only geothermal and solar
thermal belong in the same low-impact category; geothermal because it uses gas- and
oil-drilling technology to extract hot water, and low-temperature solar thermal systems
because they are usually located on rooftops and therefore do not appropriate additional
land. The footprints of high-temperature solar thermal systems (CSP) are also small, with
land impacts similar to coal and natural gas.
Figure 6.2.
A strip coal mining operation in Australia.
Source:
Stephen Codrington at
Wikimedia Commons.
Petroleum, hydropower, solar photovoltaics (PV), wind power and low-temperature
solar thermal systems for district heating belong in the second category, involving
