The
environmental impact of the energy industry is
diverse. Energy has
been harnessed by human beings for millennia. Initially it was with the use of fire for
light, heat, cooking and for safety, and its use can be traced back at least
1.9 million years. In recent years there has been a trend towards the
increased commercialization of various renewable energy sources.
Consumption of fossil fuel resources leads to global warming and
climate change. In most parts of the world little change is being made to slow
these changes. If the peak oil theory proves true, and more explorations of viable
alternative energy sources are made, our impact could be less hostile to our
environment.
Rapidly
advancing technologies can achieve a transition of energy generation, water and
waste management, and food production towards better environmental and energy
usage practices using methods of systems ecology and industrial
ecology.
Climate
Change
The scientific consensus on global
warming and climate
change is that it is
caused by anthropogenic greenhouse
gas emissions, the
majority of which comes from burning fossil fuels with deforestation and some agricultural practices being
also major contributors.
Although there is
a highly publicized denial of climate change, the vast
majority of scientists working in climatology accept that it is due to human
activity. The IPCC report Climate Change 2007: Climate Change
Impacts, Adaptation and Vulnerability predicts
that climate change will cause shortages of food and water and increased risk
of flooding that will affect billions of people, particularly those living in
poverty.
One
measurement of greenhouse gas related and other Externality comparisons
between energy sources can be found in the ExternE project by the Paul Scherrer Institut and the University of Stuttgart which was funded by the European Commission.
According to that study, hydroelectric electricity produces the lowest CO2 emissions, wind produces the second-lowest, nuclear energy produces
the third-lowest and solar photovoltaic produces
the fourth-lowest.
Similarly,
the same research study (ExternE, Externalities of Energy), undertaken from
1995 to 2005 found that the cost of producing electricity from coal or oil
would double over its present value, and the cost of electricity production
from gas would increase by 30% if external costs such as damage to the
environment and to human health, from the airborne particulate matter, nitrogen oxides, chromium VI and arsenic emissions produced by these sources, were taken into
account. It was estimated in the study that these external, downstream, fossil
fuel costs amount up to 1%-2% of the EU’s entire Gross Domestic Product (GDP), and
this was before the external cost of global warming from these sources was even
included.
The
study also found that the environmental and health costs of nuclear power, per
unit of energy delivered, was €0.0019/kWh, which was found to be lower than
that of many renewable sources including that caused by biomass and photovoltaic solar panels, and was thirty times lower than coal at
€0.06/kWh, or 6 cents/kWh, with the energy sources of the lowest external
environmental and health costs associated with it being wind power at
€0.0009/kWh.
Biofuels:
Biomass, Ethanol and Biodiesel
On the surface,
biofuels look like an ideal energy solution. Since plants absorb carbon dioxide
as they grow, crops could counteract the carbon dioxide released by cars. They
are also renewable, and can be planted to replenish supplies.
Unfortunately,
it’s not that easy. It takes a tremendous amount of energy to grow crops, make
fertilizers and pesticides and process plants into fuel. There is ongoing
debate if ethanol from corn provides more energy than it uses for growing and
processing the plants. Also, fossil fuels provide much of the energy in
biofuels production, so biofuels may not replace as much oil as they use.
Biomass
creates harmful emissions like carbon dioxide and sulfur when it is burned, but
causes less pollution than fossil fuels. Even burning wood in a fireplace or
stove can create pollutants like carbon monoxide. Burning municipal solid
waste, or garbage that would otherwise go into a landfill, can also cause
potentially dangerous emissions. Combustion of these materials must be
carefully controlled. Disposing of the resulting ash can also pose a problem,
as it may contain harmful metals like lead and cadmium.
Ethanol
is often added to gasoline, and while these mixtures burn cleaner than pure
gasoline, they also have higher “evaporative emissions” from dispensing
equipment and fuel tanks. These emissions contribute to ozone problems and
smog. Burning ethanol also creates carbon dioxide.
Biodiesel
creates less sulfur oxides, particulate matter, carbon monoxide and hydrocarbons
when burned that traditional petroleum diesel. But biodiesel creates more
nitrogen oxide than petroleum diesel.
Coal
Coal mining has
the potential to harm air, water and land quality if it is not done with proper
care. Acidic water may drain from abandoned mines underground, and the burning
of coal causes the emission of harmful materials including carbon dioxide,
sulfur dioxide and mercury. “Clean coal” technology is being developed to
remove harmful materials before they can affect the environment, and to make it
more energy-efficient so less coal is burned.
The
coal industry also restores mined land to or prepares it for more productive
uses once surface mining is done.
Geothermal
Geothermal power plants have relatively little
environmental impact—they burn no fuel to create electricity. These plants do
create small amounts of carbon dioxide and sulfur compounds, but geothermal
emissions are far smaller than those created by fossil fuel power plants.
Hydropower
While
hydropower does not cause water or air pollution, it does have an environmental
impact: Hydroelectric power plants may harm fish populations, change water
temperature and flow (disturbing plants and animals) and force the relocation
of people and animals who live near the dam site. Some fish, like salmon, may
be prevented from swimming upstream to spawn. Technologies like fish ladders
help salmon go up over dams and enter upstream spawning areas, but the presence
of hydroelectric dams changes their migration patterns and hurts fish
populations. Hydropower plants can also cause low dissolved oxygen levels in
the water, which is harmful to river habitats. Reservoirs may also lead to the
creation of methane, a harmful greenhouse gas.
Petroleum
(Oil and Gas)
Great
strides have been made to ensure that oil and gas producers make as little
impact as possible on the natural environments in which they operate. These
include drilling multiple wells from a single location to minimize damages to
the surface, using environmentally sound chemicals to stimulate well production
and restoring the surface as nearly as possible to pre-drilling conditions (as
required by landowners and state or federal agencies, who often must approve
the company’s completion of restoration activities).
When
many people think of oil and the environment, they think of oil spills. The
reality is that the exploration and production of oil rarely create an oil
spill. For decades the offshore oil and gas industry has had a strong safety
and environmental record in operating in the Gulf of Mexico, with less than
0.001 percent of the oil produced in federal waters spilled since 1980. The
Deepwater Horizon event is a stark reminder of the risks and challenges in
offshore operations. The oil and gas industry takes safety and environmental
stewardship very seriously. That is why when it is known how the Deepwater
Horizon accident occurred, the industry will work together to ensure that that
this kind of event never happens again anywhere in the world.
Most
oil spills occur primarily during transportation, mostly involving the tankers
that are used to move oil from where it is produced to where consumers need it.
But oil spills from transportation have declined significantly during the past
few years, and the growing use of double-hulled tankers provides extra
protection. Another source of oil spills during transportation is pipelines.
Unfortunately, a major reason for spills from pipelines in developing countries
is civil unrest. Weather, such as hurricanes, is another factor in
pipeline-related spills.
Urban
runoff and natural seeps are large sources of oil pollution. Urban runoff comes
from rain washing away oil drips from cars or machinery and people pouring used
oil into the gutter and using other improper disposal methods. Natural seepage
is actually the largest single source of petroleum inputs in marine
environments totaling 47%.
When
burned, petroleum products emit carbon dioxide, carbon monoxide and other air
toxins, all of which have a negative effect on the environment.
Solar
Solar
energy produces no air or water pollution or greenhouse gases. However, it has
some indirect impacts on the environment. For example, the manufacturing of
photovoltaic cells (PV) produces some toxic materials and chemicals.
Ecosystems
can also be affected by solar systems. Water from underground wells may be
required to clean concentrators and receivers, and to cool the generator, which
may harm the ecosystem in dry climates.
Uranium
(Nuclear Energy)
Nuclear
power plants produce no air pollution or carbon dioxide, but they do produce
byproducts like nuclear waste and spent fuels. Most nuclear waste is low level
(for example, disposable items that have come into contact with small amounts
of radioactive dust), and special regulations are in place to prevent them from
harming the environment. But some spent fuel is highly radioactive and must be
stored in specially designed facilities. In addition to the fuel waste, much of
the equipment in the nuclear power plants becomes contaminated with radiation
and will become radioactive waste after the plant is closed. These wastes will
remain radioactive for many thousands of years, which may not allow re-use of
the contaminated land.
Nuclear
power plants use large quantities of water for steam production and for
cooling, affecting fish and other aquatic life. Likewise, heavy metals and
salts can build up in the water used in the nuclear power plant systems. When
water is discharged from the power plant, these pollutants can negatively
affect water quality and aquatic life.
Wind
Wind
is a clean energy source. It produces no air or water pollution because no fuel
is burned to generate electricity. The most serious environmental impact from
wind energy may be its effect on bird and bat mortality. Wind turbine design
has changed dramatically in the last couple of decades to reduce this impact.
Turbine blades are now solid, so there are no lattice structures that entice
birds to perch. Also, the blades’ surface area is much larger, so they don’t
have to spin as fast to generate power. Slower-moving blades mean fewer bird
collisions.
So, although
there are many drawbacks from of energy industry, scientist has try their best
to make a better change in the last couple of decades. And we know that energy
industry has been an important thing in our life, so we should use it
efficiently and i hope we can find a way to reduce or even remove the harmness
of energy industry in the future.
References
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