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Environmental issues with energy
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Rate of world energy usage in terawatts (TW), 1965-2005.[1]
There are many environmental issues with energy with the largest being climate change
due predominantly to the burning of fossil fuels and the direct impact of greenhouse
gases on the Earths environment. In recent years there has been a trend towards the
increased commercialization of various renewable energy sources.
In the real world of consumption of fossil fuel resources which lead to global warming
and climate change however little change is being made in many parts of the world.
Chinese oil demand for instance, is projected to grow nearly 20% in the next six years,
and that country already imports over half of the 8 million barrels a day it uses.[2] If the
peak oil theory proves out, more explorations of viable alternative energy sources, could
be more friendly to the 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.[3][4]
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Issues
Climate change
Global mean surface temperature anomaly relative to 1961–1990.
Global warming and climate change due to human activity is generally accepted as being
caused by anthropogenic greenhouse gas emissions. The majority of greenhouses gas
emissions are due to burning fossil fuels with most of the rest due to deforestation.
There is a highly publicized denial of climate change but the vast majority of scientists
working in climatology accept that it is due to human activity. Some effects of human
activity in the natural world regarding the use of natural resources, has brought about dire
warnings in regard to sustainability issues by a variety of science based groups.[5]
Biofuel use
Biofuel is defined as solid, liquid or gaseous fuel obtained from relatively recently
lifeless or living biological material and is different from fossil fuels, which are derived
from long dead biological material. Also, various plants and plant-derived materials are
used for biofuel manufacturing.
Bio fuels are a renewable energy and can sustainable (carbon neutral) in terms of
greenhouse gas emissions since they are in the carbon cycle for the short term.
Bio-diesel
High use of bio-diesel leads to land use changes including deforestation.
Firewood
Unsustainable firewood harvesting can lead to loss of biodiversity and erosion due to loss
of forest cover. An example of this is a 40 year study done by the University of Leeds of
African forests, which account for a third of the world's total tropical forest which
demonstrates that Africa is a significant carbon sink. A climate change expert, Lee White
states that "To get an idea of the value of the sink, the removal of nearly 5 billion tonnes
of carbon dioxide from the atmosphere by intact tropical forests is at issue.
According to the U.N. the continent is losing forest twice as fast as the rest of the world.
"Once upon a time, Africa boasted seven million square kilometers of forest but a third of
that has been lost, most of it to charcoal."[6]
Fossil fuel use
Global fossil carbon emission by fuel type, 1800-2007 AD.
The three fossil fuel types are coal, petroleum and natural gas. It was estimated by the
Energy Information Administration that in 2006 primary sources of energy consisted of
petroleum 36.8%, coal 26.6%, natural gas 22.9%, amounting to an 86% share for fossil
fuels in primary energy production in the world.[7]
The burning of fossil fuels produces around 21.3 billion tonnes (21.3 gigatonnes) of
carbon dioxide per year, but it is estimated that natural processes can only absorb about
half of that amount, so there is a net increase of 10.65 billion tonnes of atmospheric
carbon dioxide per year (one tonne of atmospheric carbon is equivalent to 44/12 or 3.7
tonnes of carbon).[8] Carbon dioxide is one of the greenhouse gases that enhances
radiative forcing and contributes to global warming, causing the average surface
temperature of the Earth to rise in response, which climate scientists agree will cause
major adverse effects.
Coal
Coal is a made up predominately of carbon and when burnt it produces carbon dioxide,
one of the major greenhouse gases.
Petroleum
Gas
Natural gas is often described as the cleanest fossil fuel, producing less carbon dioxide
per joule delivered than either coal or oil.,[9] and far fewer pollutants than other fossil
fuels. However, in absolute terms it does contribute substantially to global carbon
emissions, and this contribution is projected to grow. According to the IPCC Fourth
Assessment Report,[10] in 2004 natural gas produced about 5,300 Mt/yr of CO2 emissions,
while coal and oil produced 10,600 and 10,200 respectively (Figure 4.4); but by 2030,
according to an updated version of the SRES B2 emissions scenario, natural gas would be
the source of 11,000 Mt/yr, with coal and oil now 8,400 and 17,200 respectively. (Total
global emissions for 2004 were estimated at over 27,200 Mt.)
In addition, natural gas itself is a greenhouse gas far more potent than carbon dioxide
when released into the atmosphere but is released in smaller amounts.
Electricity generation
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Environmental impacts of dams
Environmental concerns with electricity generation
o Phase-out of incandescent light bulbs
o Environmental effects of nuclear power
Wind power
Compared to the environmental effects of traditional energy sources, the environmental
effects of wind power are relatively minor. Wind power consumes no fuel, and emits no
air pollution, unlike fossil fuel power sources. The energy consumed to manufacture and
transport the materials used to build a wind power plant is equal to the new energy
produced by the plant within a few months. While a wind farm may cover a large area of
land, many land uses such as agriculture are compatible, with only small areas of turbine
foundations and infrastructure made unavailable for use.[11]
Mitigation
Mitigation of energy issues can be addressed by the use of sustainable practices.
Sustainable transport

Public transport, Cycling, Electric cars, Biofuels
Renewable energy
Main article: Renewable energy

Hydroelectricity, wind power, Solar energy
Economic instruments
Various economic instruments can be used to steer society toward sustainable energy.
Some of these methods include ecotaxes and emissions trading.
Ecological economics aims to address some of the interdependence and coevolution of
human economies and natural ecosystems over time and space.[12]Environmental
economics, is the mainstream economic analysis of the environment, which views the
economy as a subsystem of the ecosystem, while ecological economics emphasis is upon
preserving natural capital.[13][14]Biophysical economics sometimes referred to as
thermoeconomics is discussed in the field of ecological economics and relates directly to
energy conversion, which itself is related to the fields of sustainability and sustainable
development especially in the area of carbon burning.[15]