Environmental Effects of Energy Use

Most important environmental
impacts caused by energy sources are global climate change and acid rain – both
of which have the origin in the combustion of fossil fuels and lead to global
or transboundary effects.

Climate change; During the last few decades, concern has been
growing internationally that increasing concentrations of greenhouse gases in
the atmosphere will change our climate in ways detrimental to our social and
economic well-being. Climate change or global warming means a gradual increase
in the global average air temperature at the earth’s surface. Abundant data
demonstrate that global climate has warmed during the past 150 years. The
majority of scientists now believe that global warming is taking place, at a
rate of around 0,3 deg. C per decade, and that it is caused by increases in the
concentration of so-called “greenhouse gases” in the atmosphere. The most
important single component of these greenhouse gas emissions is carbon dioxide
(CO₂). The major source of emissions of CO₂ are power
plants, automobiles, and industry. Combustion of fossil fuels contributes
around 80 percent to total world-wide anthropogenic CO₂ emissions.

Another source is global deforestation. Trees remove carbon dioxide from
the air as they grow. When they are cut and burned that CO₂ is
released back into the atmosphere. Massive deforestation around the globe
is releasing large amounts of CO₂ and decreasing the forests’
ability to take CO₂ from the atmosphere. The second major greenhouse
gas is methane (CH₄). It is a minor by-product of burning coal, and
also comes from venting of natural gas (which is nearly pure methane).
Different fossil fuels produce different amounts of CO₂ per unit of
energy released. Coal is largely carbon, and so most of its combustion products
are CO₂. Natural gas, which is methane, produces water as well as CO₂
when it is burned, and so emits less CO₂ per unit of energy than
coal. Oil falls somewhere between gas and coal in terms of CO₂
emissions, as it is made up of a mixture of hydrocarbons. The amount of CO₂
produced per unit of energy from coal, oil and gas is in the approximate
proportion of 2 to 1,5 to 1. This is one of the reasons why there is a move
towards greater use of natural gas instead of coal or oil in power stations,
despite the much greater abundance of coal.

The earth’s atmosphere is made up of several gases, which act as a
“greenhouse”, trapping the sun’s rays as they are reflected from the earth’s surface.
Without this mechanism, the earth would be too cold to sustain life as we know
it. Since the industrial revolution, humans have been adding huge quantities of
greenhouse gases, especially carbon dioxide (CO₂) to the atmosphere.
More greenhouse gases means that more heat is trapped, which causes global
warming. By burning coal, oil and natural gas increases atmospheric
concentrations of these gases. Over the past century, increases in industry,
transportation, and electricity production have increased gas concentrations in
the atmosphere faster than natural processes can remove them leading to
human-caused warming of the globe.



Acid
rain
; Another side effect of fossil
fuels combustion and resulting emissions of pollutants is acid rain (or acid
deposition). In the process of burning fossil fuels some of gases, in
particular sulphur dioxide (SO₂) and nitrogen oxides (NO_x)
are created. Although natural sources of sulphur oxides and nitrogen oxides do
exist, more than 90% of the sulphur and 95% of the nitrogen emissions occurring
in North America and Europe are of human
origin. Once released into the atmosphere, they can be converted chemically
into such secondary pollutants as nitric acid and sulphuric acid, both of which
dissolve easily in water. The result is that any rain which follows is slightly
acidic. The acidic water droplets can be carried long distances by prevailing winds,
returning to Earth as acid rain, snow, or fog.

Natural factors such as volcanoes, swamps and decaying plant life all
produce sulphur dioxide, one of the contributing gases to acid rain. These
natural occurrences form some kind of acid rain. There are also some cases
where acid rain may be produced naturally, which is also bad for the
environment but occurs in much lower amounts and quantities than that of those
found in urban areas. Between the 1950’s and the 1970’s the rain over Europe increased in acidity by approximately ten times.
In the 1980’s however, acidity levels decreased, but although many countries
have started to do something about pollution that causes acid rain, the problem
is not going away. Acid rain is often phrased as “acid precipitation”. On the
pH scale, rain usually measures 5.6. Anything below this measurement is said to
be acidified rainfall. The chemical equation for acid rain is as follows:

SO₂
(Sulphur
dioxide) + NO (Nitrogen Oxide) + H₂O (Water) = Acid rain

Water solutions vary in their degree of acidity. If pure water is
defined as neutral, baking soda solutions are basic (alkaline) and household
ammonia is very basic (very alkaline). On the other side of this scale there
are ascending degrees of acidity; milk is slightly acidic, tomato juice is
slightly more acidic, vinegar, lemon juice is still more acidic, and battery
acid is extremely acidic. If there were no pollution at all, normal rainwater
would fall on the acid side of this scale, not the alkaline side. Normal rainwater
is less acidic than tomato juice, but more acidic than milk. What pollution
does is cause the acidity of rain to increase. In some areas of the world, rain
can be as acidic as vinegar or lemon juice.

This acid rain can cause damage to plant life, in some cases seriously
affecting the growth of forests, and can erode buildings and corrode metal
objects. The primary component involved in corrosion is acid rain. It is
estimated that the damage to metal buildings alone amounts to about 2 billion
dollars yearly. The highest emissions of sulphur come from those sectors, which
use the most energy and the highest sulphur-content fuels, that is solid fuels
and high sulphur heavy fuel oil. Solid fuels are the most polluting fossil
fuels locally and globally. These fuels range from hard coals to soft brown
coals and lignites, which have high proportion of combustion waste and
pollutants such as sulphur, heavy metals, moisture and ash content.

One of the major problems with acid rain is that it gets carried from a
mass acid rain producing area to areas that are usually not as badly affected.
Tall chimneys that are built to ensure that the pollution that is produced by
factories is taken away from nearby cities, puts the pollution into the
atmosphere. When the moisture in the air picks up these particles, they form
acids. As a result they become a part of the clouds. Then these clouds get
carried off by wind, which means that when the rain falls it may be a long
distance away from where the acidic particles were picked up from. An example
of this would be Central and Eastern Europe and Scandinavia.
Sweden
suffer from acid rain because of huge sulphur emissions from Eastern European
power plants with low emission standards and because of wind blowing the
particles over to their country.

Bad air quality; Beside greenhouse gases, SO₂ and
NO_x emissions that cause acid rain, emissions of particulate matter
contribute to bad air quality. Fuel combustion is the most important source of
anthropogenic nitrogen oxides, while fuel combustion and evaporative emissions
from motor vehicles are the main sources of anthropogenic volatile organic compounds
(VOC_s). Motor vehicles account for a considerable fraction of the
total emissions of nitrogen oxides and VOC_s in Europe and North America. NO_x emissions also contribute
to the formation of tropospheric photochemical oxidants. Photochemical
oxidants, especially ozone (O₃), are among the most important trace
gases in the atmosphere. Their distributions show signs of change due to
increasing emissions of ozone precursors (nitrogen oxides, or VOCs, methane and
carbon monoxide

According to World Health Organisation air quality guidelines for ozone
limit values are frequently exceeded in most parts of developed countries. In
the lower troposphere, close to the ground, ozone is a strong oxidant that at
elevated concentrations is harmful to human health, materials and plants. In
the upper troposphere, ozone is an important greenhouse gas and contributes
greatly to the oxidation efficiency of the atmosphere.


There are reported several ozone and other photochemical oxidants effects on
human health, materials, and crops. Increased ozone level can cause premature
ageing of lungs and other respiratory tract effects like impaired lung function
and increased bronchial reactivity. Increased incidence of asthmatic attacks,
and respiratory symptoms, have been observed. Ozone contributes to damage to
materials such as paint, textile, rubber and plastics. In the case of crops and
some sensitive natural types of vegetation or plant species, exposure to ozone
will lead leaf to damage and loss of production. Other photochemical oxidants
cause a range of acute effects including eye, nose and throat irritation, chest
discomfort, cough and headache. As a second consequence of increases in global
trace gas emissions, a further decrease is expected to occur of the
self-cleansing capacity of the troposphere. This would result in longer
atmospheric residence times of trace gases and, consequently, an enhanced
greenhouse effect and an increased influx of ozone-depleting trace gases into
the stratosphere.

Heavy metals like arsenic (As), cadmium (Cd), mercury (Hg), lead (Pb)
and zinc (Zn) are also released during fuel combustion. Lead pollution as the
result of road traffic emissions have decreased markedly since early 80s due to
increased consumption of unleaded gasoline and use of catalysts in cars.
Nevertheless this sector remains the main source of lead in atmosphere. Beside
emissions of pollutants there are also some other impacts of fossil fuel
combustion on local environment. Here microclimatic impacts like origination of
fogs, less sunshine etc. are the results of large amounts of water vapour
effluents from cooling towers of power plants.

Sea pollution; Damage caused by the
transport of oil is related to the pollution of the seas. Here as the scale of
oil production has increased during the twentieth century, the quantity of oil
transported around the world, most of it by the sea, has also increased. To
cope with this increase, in a highly competitive market, the size of oil
tankers has increased to the point where they are by far the largest commercial
ships. Even in routine operation, this results in large quantities of oil being
released into the seas. The tankers fill up with water as ballast for return
journeys. When this is emptied, significant quantities of oil are released as
well.

Despite the fact that the transport of oil is generally a
safe industry, the scale of it, and the size of tankers, means that when
accidents do occur they have a large effect. Although the number of accidents
is small in proportion to the number of tanker journeys, thousands of minor
incidents involving oil spills from tankers, and oil storage facilities occur
annually.

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Reserves of Fossil Fuels

Fossil fuels are valuable natural energy sources that required several
millions of years for their creation but are now rapidly being depleted. The
prominent worry that fossil fuels will run out was reported almost 30 years ago
by the influential book Limits to Growth. This book reported a series of
computer simulations of future resource use in which world fuel consumption
continued to rise exponentially. The predicted result was an ultimate collapse
in fuel supplies, regardless of the amount of fuel assumed to be available.

These fears came into sharp focus in the 1973 fuel crisis, when the
member nations OPEC were able for the first time to co-ordinate their policies
and raised the price of oil dramatically. One of the factors which gave the
OPEC states the power to exert their influence so strongly was that the USA,
formerly a major exporter of oil , had become an importer. United States had used up most of the easily
obtainable oil from the Texas
oil fields.

The shortage expected in the dramatic concerns of those days do not seem
imminent at present. The general principle that the amount of fossil fuels
remaining is ultimately limited and cannot last for ever is obviously true, but
estimating how long they will last is not a simple process. In any year, newly
reported figures for „proven reserves“ of oil, gas and coal are available.
Proven reserves are generally taken to be those quantities which geological and
engineering information indicate with reasonable certainty can be recovered in
the future from known deposits under existing economic and operating
conditions. A useful figure of the merit for fuel reserves is the
reserve/production ratio.

If the proven reserves remaining at the end of any year are
divided by the production (consumption) in that year, the result is the time
that those remaining reserves would last if production were to continue at the
then-current level. According to the British Petroleum statistics the
reserves/production (R/P) ratio of the world’s fossil resources is estimated
as: 40, 62, and 224 years for oil, natural gas, and coal respectively.

Like the fossil fuels, uranium is also one of the depletable natural
resources. If uranium is only used in a once-through cycle where it is burned
in a reactor only once and disposed as a waste thereafter, confirmed reserves
are destined to be depleted in the next 60 years. The reserves/production ratio
for any region also gives an indication of the dependence of that area on more
favoured regions. For example, for oil, the reserve/production ratio was
less than 10 years for Western Europe and for North
America it was about 25 years. Obviously, both regions would be in
dire straits if they could not import oil from Middle East,
where the ratio is nearly 100 years. The Middle East has some 60 % of the
world’s reserves of oil, and Saudi
Arabia alone contains about 25 %. For gas
the situation is somewhat different, because of the massive reserves in the
former Soviet Union. This region holds some 40
% of the worlds reserves of gas, and another 40% of gas is in the OPEC region.
The world as a whole is greatly dependent upon a limited number of regions
which have most of the reserves. The reserve/production ratio for coal are much
larger and much more evenly distributed. Unfortunately, coal has disadvantages
compared to oil and gas. Coal burning creates more CO2 per unit of energy
released than is the case with gas and oil, and more sulphur dioxide and
nitrogen oxides.

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How Much is Energy Consumed Globally?

Each year, the equivalent of approx. 10 000 million tons of coal is consumed on earth as energy. About 40 % from this is based on oil and together with coal and natural gas more than 90 % of the total energy consumption result from carbon atoms in these fossil fuels. The consequence will be a global warming (greenhouse effect) and the lack of resources in the future. Today fossil fuels such as coal, oil and natural gas account for 90% of total primary energy supply. Estimated total world consumption of primary energy, in all forms (including non-commercial fuels like biomass), is approximately 400 EJ per year, equivalent of some 9500 million tonnes of oil (mtoe) per year.

The magnitude of energy problem that may face future generations can be illustrated by the simple calculation. The population of the world in 1990 was approximately 5 billion people. The UN estimates of population trends show it continuing to increase to around 8 billion by 2025, but stabilising towards the end of the next century at somewhere between 10 and 12 billion people. Most of that increase will be in the less developed countries. According to the US DOE (Department of energy) outlook for energy use throughout the world continues to show strong prospects for rising levels of consumption over the next two decades, led by growing demand for end-use energy in Asia. World energy demand in 2015 is projected to reach nearly 562 quadrillion British thermal units (Btu).

The expected increment in total energy demand between 1995 and 2015 - almost 200 quadrillion Btu - would match the total world energy consumption recorded in 1970, just before the energy crisis of 1973. Two-thirds of all energy growth will occur in developing economies and economies in transition, with much of that growth concentrated in Asia. Energy growth in the developing countries of Asia is projected to average 4.2 percent per year, compared with 1.3 percent for industrialized economies. The U.S. growth rate is expected to average only about 1 percent per year. As recently as 1990, U.S. energy consumption exceeded total consumption in the nations of developing Asia by 33 quadrillion Btu. By 2015, energy use in developing Asia is expected to exceed U.S. consumption by 48 quadrillion Btu.

According to the report of US DOE by 2015, oil use is expected to exceed 100 million barrels per day, a consumption rate 50 per cent greater than in 1995. Oil trading patterns are expected to shift markedly as oil consumption in Asia Pacific areas far outpaces domestic production gains, leading to a large increase in imports from Middle East suppliers. World-wide, coal use is projected to exceed 7.3 billion tons by 2015, compared with 5.1 billion tons in 1995. Growth in coal use will be regionally concentrated, occurring for the most part in India and China.

Natural gas is expected to have the highest growth rate among fossil fuels, at 3.1 percent a year, gaining share relative to oil and coal. By 2015 natural gas consumption on a Btu basis will exceed the total oil consumption recorded for 1995, at a level equivalent to two-thirds of the oil consumption projected for 2015. Natural gas consumption in 1995 was only about 55 percent of oil consumption. According to US DOE prediction only about 8 percent of projected growth in energy demand over the next two decades will be served by non-fossil fuel sources. In fact, the non-fossil (commercial) fuel share of world energy consumption declines from 15 percent to 12 percent over the projection period. Thus, world carbon emissions are likely to increase by 3.7 billion metric tons, or 61 percent, over the 1990 level by 2015. The Climate Change Convention of 1992 commits all signatories to search for and develop policies to moderate or stabilize carbon emissions. However, even if all the developed countries were able to achieve stabilization of their emissions relative to 1990 levels, overall world carbon emissions would still rise by 2.5 billion metric tons over the next two decades.

Per capita energy use in the world’s industrialized economies, which far exceeds the levels in newly emerging economies, is expected to change only moderately in the next two decades. In some emerging economies (for example, India and China), per capita energy use may double. Even with such growth, however, average per capita energy use in the developing countries will still be less than one-fifth the average for the industrialized countries in 2015.

In the longer term, consumption of oil as the principal source of commercial energy today, will start to decline after the transition phase (between 2020 and 2060). It is expected that natural gas will continue to be used as long as price and availability are satisfactory but as reserves reduce or prices rise coal (which is usually less expensive than natural gas and its international prices are unlikely to rise) will command a greater proportion of the market. To maintain energy levels and because of world-wide environmental concerns some experts predict that coal will have to be utilized cleanly, where gasification process will be the most environmentally friendly way of its future utilization.

The transition to a sustainable energy system requires that share of renewable energy sources will continually grow. Renewables combined with a system of new technologies, can contribute to a considerable extent to energy requirements in the time horizon beyond 2020. Report for the UN Solar Energy Group for Environment and Development suggests that using technology already on the market or at the advanced engineering testing stage, by the middle of the next century renewable energy sources could account for 60 percent of the world’s electricity market and 40 percent of the market for fuels used directly

The Importance of Renewable Energy

From the beginning human energy demands were covered only by renewable energy sources – sun, biomass, hydro and wind power. But, it was only until the start of industrial revolution and the ability to transform heat into motion, when energy consumption and industrial development accelerated rapidly. The industrial revolution was a revolution of energy technology based on fossil fuels. This occurred in stages, from the exploitation of coal deposits to oil and natural gas fields on a global scale. It has been only half a century since nuclear power began being used as an energy source. After this fossil-based era world nears the beginning of another major transition, away from fossil fuels and towards renewable energy sources once again. Fundamental shift in the energy picture can be found in the enormous increase of energy demand since the middle of the last century. That increase is the result not only of industrial development but also of population growth. World population grew 3.2 times between 1850 and 1970, per-capita use of industrial energy increased about 20-fold, and total world use of industrial and traditional energy forms combined increased more than 12-fold.

In recent years, there has been a greater interest in the issue of energy, especially renewable energy. This interest has not been the result of rapidly increasing energy prices — non-renewable energy, including oil, is abundant and relatively inexpensive. Rather, the renewed interest has been because of environmental concerns, especially the burning of fossil fuels, which many believe contributes significantly to acid rain and global warming. Public policy issues involving energy have tremendous economic implications. To ensure wise public policy, citizens and decision makers must not only understand basic facts about energy sources, but also must know how to apply basic economic concepts in their analysis of energy issues.

General problem isn’t that we use energy, but how we produce and consume energy resources. As long as we continue to cover our energy needs primarily by combustion of fossil fuels or nuclear reactions, we are going to have the problems, the environmental impacts, social, and sustainability problems. What we really need are energy sources that will last forever and can be used without pollution of the environment.

What is actually Renewable Energy

The term”renewable energy” (also usually called alternative energy) encompasses a variety of power generation sources. It refers to energy resources that occur naturally and repeatedly in the environmental and can be harnessed for human benefit. Some examples of renewable energy systems are solar, wind, and geothermal energy. We also get renewable energy from trees and plants, rivers, and even garbage. Renewable energy encompasses many different types of technology at different stages of development and commercialisation, from the burning of wood for heat in the residential sector to wind-generated electricity to processes such as biomass gasification for electricity generation

The advantages of using renewable energy sources are considerable. From an environmental standpoint, solar, wind and waterpower are all non-emission power sources. No harmful exhaust is produced when using alternative energy generators as usually yielded by combustion power plants. There is also no worry about toxic or radioactive waste products, as there is with nuclear power. In addition to the lack of emissions and waste products, no valuable resources are used up with renewable resource power generation.

Renewable Energy Conciousness Through Education

As the environmental problems caused by the increased utilization of fossil fuels are becoming more severe and to meet the increasing demand for energy, alternatives clean energy resources need to be explored along with conserving existing resources. Consciousness of importance of renewable energy and its possibilities to be exploited and developed should be socialised and introduced. It can be done through the formal education.

The poor dissemination of renewable energy technologies may be attributed to several factors. One of the important inhabiting factors is the lack of a structured framework for providing energy education, in general, renewable energy education, in particular. For example, in many countries, the lack of indigenous technology development capability in the area of new and renewable sources of energy has often resulted in the promotion of very expensive and inappropriate designs. Similarly, in some other places, owing to the unavailability of local technical manpower for proper repair and maintenance of the initially installed systems, the user have decided to use some other energy resource-technology combinations. Some of the renewable energy technologies were not accepted by the end users as they were unaware of their potential benefits and associated requirements (Kandpal and Garg, 1996)
Studies indicate that renewable energy related education is an area in which very little has been done, not only in developing countries but also in developed countries. This absence of any ambitious educational programme results mainly from two factors: the breadth and interdisciplinary nature of the subject, and the lack of recognition that renewable energy will be great importance in the decades to come (Panangkis at al. 1995)

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