Environmental Engineering Reference
In-Depth Information
ground subsidence. Fluid reinjection helps to maintain pressures in the reservoir and avoid
subsidence.
Geothermal energy belongs in the lowest category of land use impact. However, one of
thebiggestconstraintsongeothermalenergyistheissueoflandscapeimpact.Theinsulated
steel pipelines that carry steam and hot water to a power plant from drilling points have
a major visual impact on the landscape. They also act as barriers to grazing animals and
tractors. There are, however, several successful examples of how geothermal energy can
be reconciled with tourism in places of great scenic beauty, including Wairakei in New
Zealand and the Blue Lagoon in Iceland (see
Figure 6.15
)
(Goldstein et al.
2011
)
.
Figure 6.15.
These two geothermal energy plants produce visible impacts on the
landscape, though hikers are still free to roam at Larderello (Italy), and the buildings in a
formerly pristine landscape at the Blue Lagoon (Iceland) do not seem to bother the
bathers.
Sources:
above, Gian Andrea Pagnoni; below, Mark Hintsa at Flickr.
6.10 The Impacts of Ocean Energy
The physical presence of new structures may affect marine ecosystems, both above and
belowthesurface.Somefish,suchassalmonandeel,migratebetweenfreshandsaltwaters
to spawn, and marine energy devices may act as a physical barrier. Rotors can also injure
or kill fish or dolphin in a similar manner to wind turbines striking birds and bats, although
the blades of water turbines, for current or tidal energy, move at much slower speeds than
wind turbines do, and thus the likelihood of blade strike is lower.
Like conventional power plants, which use natural watercourses as a coolant, ocean
thermal energy conversion (OTEC) devices exchange large volumes of deep and shallow
water to take advantage of the difference in temperature. If pursued on a large scale, this
practice would negatively affect the marine plants and animals in both strata. Moreover,
large pipes would run along the ocean floor, altering the environment for planktonic
However, in 2001, the British Government concluded that “the adverse environmental
impact of wave and tidal energy devices is minimal and far less than that of nearly any
other source of energy, but further research is required to establish the effect of real
