WHY DO WE NEED RENEWABLES ?

ENERGY TODAY
Most of the energy we use today comes from fossil fuels. Coal, oil, and natural gas are all fossil fuels created several millions of years before by the decay of plants and  animals. These fuels lie buried between layers of earth and rock. While fossil fuels are still being created today by underground heat and pressure, they are being consumed much more rapidly than they are created. For that reason, fossil fuels are considered as non-renewable; that is, they are not replaced as soon as we use them. So, we will run out of them sometime in the future. Moreover burning fossil fuels leads to pollution and many environmental impacts. Because our world depends so much on energy, we need to use sources of energy that will last forever. These sources are called renewable energy. Moreover these renewable energy sources are much more environmentally friendly than fossil fuels when they are burned.

Among fossil fuels somehow special character has uranium-nuclear fuel which can be exhausted in less than 100 years, but in so called breeder reactors it can multiply and last much more. Nevertheless problems with radioactive waste, which will present a danger for millions of years and the the impact of accident in Chernobyl, which showed a risk connected with nuclear energy, most governments in industrialised world are now abandoning nuclear power completely. This development continues despite the fact that nuclear energy, which produce almost zero emissions of greenhouse gases, can be somehow a solution to global climate change (see bellow). Emissions of greenhouse gases are now recognised as the most important force behind the efforts to decrease consumption of fossil power.

WHY DO WE NEED THE CHANGE IN ENERGY USE ?
The main 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.

ENERGY CONSUMPTION – SUSTAINABILITY PROBLEM

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.
 

History of energy consumption
Ancient discovery of fire and the possibility of burning wood made available, for the first time, fairly large amount of energy for mankind. Later (4000 and 3500 years B.C.) after the first sailing ships and windmills were developed and the use of hydropower began via water mills or irrigation systems, cultural development began to accelerate. For several thousands years human energy demands were covered only by renewable energy sources – sun, biomass, hydro and wind power. 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.

HOW MUCH ENERGY DO WE USE ?
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 a equivalent of almost  10.000 million tonnes of oil (mtoe) per year.
 
 

World  Energy Consumption in 2000
	World Mtoe	USA %	EU-15 %	Japan %	Russia %	China* %	India %
All Fuels	9977,7	23,1	14,9	5,3	6,2	11,4	5,2
Solid fuels	2336,0	23,2	9,4	4,1	4,7	28,1	7,5
Oil	3482,7	25,6	17,2	7,5	3,7	6,4	3,2
Natural gas	2112,4	26,0	16,3	3,1	15,1	1,3	1,1
Nuclear	680,4	30,6	33,8	12,3	5,1	0,6	0,6
Renewables	1367,1	8,0	6,7	1,2	1,5	17,1	15,2
Hydro	227,4	9,6	12,8	3,3	6,2	8,4	2,8
Geothermal	43,5	30,1	7,9	6,6	0,1	0,0	0,0
Wind/Solar	7,2	27,4	37,8	12,6	0,0	0,0	1,9
Biomass	1089,0	6,7	5,2	0,5	0,6	19,7	18,5
Source: Commission services, Organisation for Economic Co-operation and Development						* Includes Hong Kong

FUTURE TRENDS
The magnitude of energy problem that may face future generations can be illustrated by the simple calculation. The population of the world in 2000 was approximately 6 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.

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.

Reserves of Fossil Fuels
Fossil fuels are valuable natural energy sources which 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.

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.

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.

OIL

Note Gb/a - giga barrels per year (giga = billion ).

Exploration for oil, the most important fossil fuel today, is a very expensive business. The amount of exploration is dependent upon economic conditions, particularly the price of oil, and upon political conditions. The world’s proven reserves of oil have increased from some 540 billion barrels in 1969 to just over 1000 billion barrels in 1992, but this does not mean that potential reserves are unlimited. The earth has been surveyed in great detail by the oil companies, and the easiest, cheapest and most promising reservoirs have all been found.

NATURAL GAS

In 1970, world-wide annual consumption of natural gas was 850 billion cubic meters. Today, annual consumption is over 2000 billion cubic meters and is increasing at 3.5 percent per year. A 3.5 percent annual increase in consumption will deplete natural gas reserves by 2050. However, the increase in consumption of natural gas is accelerating at an astonishing rate. Cheap supplies of natural gas will be depleted by 2040.

This fact is recently completely neglected by power companies which are building new natural gas power stations to give customers in their area cheaper and cleaner electricity. Experts believe that by 2010, the supply of electricity from new natural gas power facilities will jump to 100,000 megawatts in USA alone. Natural gas power plants are attractive to investors. They have relative short pay back time (an average six year in the USA) and can produce electricity for a cheap rate of two to three US cents per kilowatt-hour. It seems clear that the demand for natural gas fuel will increase in the near future but will slow down in the second half of the next century.

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.

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.

HOW GLOBAL WARMING WORKS

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.

THE EVIDENCE
Recently, alarming events that are consistent with scientific predictions about the effects of climate change have become more and more commonplace. The global average temperature has increased by about 0.5 deg. C and sea level has risen by about 30 centimetres in the past century. 1998 was the hottest year since accurate records began in the 1840s, and ten of the hottest years have occurred during the last 15 years.

The following are events which consistent with scientists predictions of the effects of global warming. The past two decades have witnessed a stream of new heat and precipitation records. Glaciers are melting around the world. There has been a 50 percent reduction in glacier ice in the European Alps since 1900. Alaska’s Columbia Glacier has retreated more than 12 kilometres in the last 16 years while temperatures there have increased. A huge section of an Antarctic ice shelf broke off. Some scientists think this may be the beginning of the end for the Larsen B ice shelf, which is about the size of Connecticut. Severe floods like the devastating Midwestern floods of 1993 and 1997 are becoming more common. Infectious diseases are moving into new areas. Corresponding with global warming, sea levels have risen, and climatic zones are shifting. All these changes exemplify the environmental impact of global climate change. Global warming and climate change pose a serious threat to the survival of many species and to the well-being of people around the world.

FUTURE IMPACTS OF CLIMATE CHANGE
The IPCC estimates that air temperatures will increase by another 1-3,5 deg. C, and sea levels may rise by up to 1 meter over the next 100 years. Changes of this magnitude will affect many aspects of our lives. Here are some of them :

Seas level will rise. Rising sea level will erode beaches and coastal wetlands  destroying essential habitat and leaving coastal areas more prone to flooding. Just a 50 centimetres sea level rise would double the global population at risk from storm surges. Food crop yields will be affected. A warmer climate will increase irrigation demands and the range of certain pests, but it will also extend the growing season for some areas. While some countries will find their food production increases with a warmer climate, the poorest countries that are already subject to hunger are likely to suffer significant decreases in food production. More people will die from heat stress. Severe heat waves like the one that killed hundreds of people in Chicago in 1995 will become more frequent. Children and the elderly are most vulnerable to heat stress. Tropical diseases will spread. Infectious diseases such as Malaria, Dengue fever, encephalitis, and cholera that are spread by mosquitoes and other disease-carrying organisms which thrive in warmer climates will be able to advance into new areas. This will lead to more incidents like malaria outbreaks in New Jersey and Dengue fever in Texas.

The water cycle will be disrupted. As the water cycle intensifies, some areas will experience more severe droughts, while others will have increased flooding. This variability will stress areas that are already prone to water quality and quantity problems. Endangered species will suffer. Some of the most vulnerable plants, animals, and ecosystems will suffer major changes. Ten species at high risk from global warming are: Giant Panda, Polar Bear, Indian Tiger, Reindeer, Beluga Whale, Rockhopper Penguin, Snow Finch, Harlequin Frog, Monarch Butterfly, and Grizzly Bear. Coral reefs will be harmed. Overheating of ocean waters, as a result of global warming, can lead to coral bleaching, which is a breakdown of the complex biological systems that corals have evolved in order to survive.

Climate Change - Vital Graphics + IPCC Report 

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 (NOx) 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:

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 these particles get picked up by the moisture in the air, 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.

DAMAGE TO TREES AND SOIL

When acid rain falls, it can effect forests as well as lakes and rivers. In many countries around the world, trees are suffering greatly because of the results of acid rain. A lot of trees are losing their leaves and thinning at the top. Some trees are affected so severely that they are dying. To grow, trees need healthy soil to develop in. Acid rain is absorbed into the soil making it virtually impossible for these trees to survive. As a result of this, trees are more susceptible to viruses, fungi and insect pests and they are not able to fight them and they then die.

DESTRUCTION OF BUILDINGS
Acid rain can have a severe effect on buildings. Materials such as stone, stained glass, paintings and other objects can be damaged or even destroyed. It slowly, but gradually, eats away at the material until there is virtually nothing left. Building materials crumble away, metals are corroded, the colour in paint is spoiled, leather is weakened and crusts form on the surface of glass. In certain parts of the world many famous and ancient buildings are been damaged by acid rain. St. Paul’s’ Cathedral in London is having it’s stone work eaten away by acid rain. In Rome the Michelangelo statue of “Marcus Aurelius” has been removed to protect it from air pollution.

ACID RAIN AND LAKES
Acid rain damages soil when it falls onto the ground. It also has a noticeable effect when it falls directly into or is washed into lakes. Most of the animal and plant life in clean lakes and rivers are unable to tolerate acid rain. They can be poisoned by substances that the acid washes out from the surrounding soil into the water. All over the world there are examples of plant life and animal life suffering a lot or even not surviving the effects of acid rain. For example, thousands of lakes in Scandinavia are without any kind of life, whether it be animal or plant. Over the past years they have received a lot of acid rain as a result of the wind blowing the particles into their country form places such as England, Scotland and Eastern Europe. Since the 1930’s and 40’s some Swedish lakes have increased acidic levels in their rain water  by up to 1,000 times.

The interactions between living organisms and the chemistry of their aquatic habitats are extremely complex. If the number of one species or group of species changes in response to acidification, then the ecosystem of the entire water body is likely to be affected through the predator-prey relationships of the food web. At first, the effects of acid deposition may be almost imperceptible, but as acidity increases, more and more species of plants and animals decline or disappear. As the water pH approaches 6.0, crustaceans, insects, and some plankton species begin to     disappear.  As pH approaches 5.0, major changes in the makeup of the plankton community occur, less desirable species of mosses and plankton may begin to invade, and the progressive loss of some fish populations is likely, with the more highly valued species being generally the least  tolerant of acidity. Below pH of 5.0, the water is largely devoid of fish, the bottom is covered with undecayed material, and the near shore areas may be dominated by mosses. Terrestrial animals dependent on aquatic ecosystems are also affected. Waterfowl, for example, depend on aquatic organisms for nourishment and nutrients. As these food sources are reduced or eliminated, the quality of habitat declines and the reproductive success of the birds is affected. Both natural vegetation and crops can be affected.

HUMAN HEALTH

We eat food, drink water, and breathe air that has come in contact with acid deposition. Canadian and U.S. studies indicate that there is a link between this pollution and respirator problems in sensitive populations such as children and asthmatics. Acid rain also makes some toxic elements, such as aluminium, copper, and mercury more soluble. Acid deposition can increase the levels of these toxic metals in untreated drinking water supplies. High aluminium concentrations in soil can also prevent the uptake and use of nutrients by plants.

 BAD AIR QUALITY

Beside greenhouse gases, SO2 and NOx 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 (VOCs). Motor vehicles account for a considerable fraction of the total emissions of nitrogen oxides and VOCs in Europe and North America. NOx 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.

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. Between 1970 and 1985 there were 186 major oil spills each involving more than 1300 tonnes of oil. In 1989, the tanker Exxon Valdez ran aground off Alaska, releasing 39.000 tonnes of oil to form a slick covering 3.000 square kilometres and causing widespread environmental damage. People usually tend to think of the seas as a vast reservoir which can soak up limitless quantities of whatever we put into it. In fact, the scale of pollution from oil is such that clumps of floating oil are now common almost anywhere in the world’s oceans.

Oil trade movements

Source : BP statistics 2004

SOCIAL PROBLEMS RELATED TO ENERGY USE
Beside environmental problems associated with large-scale use of fossil and nuclear fuels and the problems with sustainability there are also social problems arising from present trends of energy utilization.

Political and economic problems
In the earlier stages of the industrial revolution, fuel sources were local and widely distributed. Industrial activity tended to grow in areas where local sources of coal were available. As the transport associated with industrialisation spread and developed, fuels began to be transported from more and more distant places. Now, with the most accessible sources of oil and gas depleted, fuels are transported around the world from small number of major producing areas. The result is that the major industrial nations have become dependent upon supplies from those producing nations, in particular oil from the Middle East, and are highly vulnerable to disruption of these supplies. This vulnerability and dependence has been a major factor shaping world politics. A series of major economic and political crises has resulted from Sues crisis in 1956 to the 1970s, oil crisis to the Gulf war in early 1990s and even the war in Iraq can be linked to the huge resources of oil in this country.Since the producing nations are generally weak militarily and the consuming nations are generally stronger, latter are under pressure to dominate the former economically, politically and if necessary, militarily to maintain access to oil (most important fuel today).
 

Oil price depends on political situation and each conflict in oil sensitive region leads to higher energy prices. World economy is thus shaped with such conflicts.

Source : BP statistics 2004

VULNERABILITY DUE TO CENTRALISATION
A related aspect of vulnerability in the present form of industrialisation is the centralized nature of fuel production and distribution. Electricity is generated in relatively few, very large power stations, and distributed through the country. Oil is imported in giant tankers, and converted to fuel in large refineries for further distribution. Concerns have been expressed that these large, vital installations offer potential target for terrorists or military opponents. As has been seen in recent years in the Middle East (Gulf War), the result can be massive ecological damage as well as economic devastation. The normal response to such vulnerability is to put greater resources into security and to increased level of protection. High level of centralisation leads also to problems with employment. Decentralized energy production and utilization which is the case of renewable energy sources can create much more new jobs than centralized fossil fuel installations.
 

MILITARY DANGERS FROM NUCLEAR PROLIFERATION
Nuclear weapon proliferation is one of the biggest threat to the world peace today with several countries already in or trying to be a member of “nuclear club”. In developed countries nuclear electricity industries grew out of nuclear weapons development. The earliest nuclear reactors were built to produce material for nuclear bombs. There has always been a close connection between the two terms of the technology used, so that military spending on research and development for nuclear weapons technology has in effect been a major subsidy for civilian nuclear electricity industries. Nuclear fuel is not directly useful for nuclear weapons. Much further processing is needed. However, for a country wishing to develop nuclear weapons without publicly revealing the fact, an obvious approach would seem to be combine weapons development with a nuclear electricity generation industry.

RENEWABLE ENERGY SOURCES
Fortunately, solutions exist to cut greenhouse gas emissions, reduce acid deposition, improve air quality and to solve social problems related to recent energy use. Shifting investment from fossil fuels like coal and oil to renewable energy and energy efficiency would allow cleaner, more sustainable sources of energy to take their rightful place as market leaders.

Renewable energy systems use resources that are constantly replaced and are usually less polluting. All renewable energy sources – solar energy, hydro power, biomass and wind energy have their origin in activity of the Sun. Geothermal energy which, because of its inexhaustible potential, is sometimes considered as renewable source is getting energy from the heat of the earth.

Renewable energy is a domestic resource which has the potential to contribute to or provide complete security of energy supply. Countries that depend on imports of fossil fuel resources are in danger due to the risk of sharp rise of the cost of imported energy (mainly oil). This is particularly so for developing countries, where the oil import bill adds every year to the problem of financing an already large external deficit.

1.Amount of Solar energy falling on Earth in one year. 2. Present solar energy use. 3. Natural gas reserves. 4. Coal reserves of coal. 5. Oil reserves.  6. Uranium reserves. 7. World energy consumption in one year.

FUTURE OF RENEWABLES
The shape of our future will be largely determined by how we generate and apply technological innovation the most powerful force for progress in the modern world. The renewable energy sources are able to have a strong transformative effect on the whole of society in the coming decades. By virtually all accounts, renewable energy resources will be an increasingly important part of the power generation mix over the next several decades. Not only do these technologies help reduce global carbon emissions, but they also add some much-needed flexibility to the energy resource mix by decreasing our dependence on limited reserves of fossil fuels. Experts agree that hydropower and biomass will continue to dominate the renewables arena for some time. However, the rising stars of the renewables world - wind power and photovoltaics - are on track to become strong players in the energy market of the next century. Wind power is the fastest-growing electricity technology currently available. Wind-generated electricity is already competitive with fossil-fuel based electricity in some locations, and installed wind power capacity now exceeds 10,000 MW world-wide. Meanwhile, PV electricity - although currently three to four times the cost of conventional, delivered electricity - is seeing impressive growth world-wide. PV is particularly attractive for applications not served by the power grid. Advanced thin-film technology (a much less expensive option than crystalline silicon technology) is rapidly entering commercial-scale production.

The BP gasoline station with photovoltaic panels on the roof.

Perhaps even more promising than the technical developments in renewables are the resounding endorsements from major energy companies like Enron, Shell, and British Petroleum, which have invested heavily in PV and wind in recent years and are planning significant increases in these and other renewables efforts.
The energy-starved developing world, which accounts for a large portion of the projected new electricity demand over the next 20 years, is considered one of the biggest markets for renewables. Many of these countries are attracted to the  modular nature of renewable energy technologies, which can be located close to the users. The renewable technologies are far cheaper and quicker to install than central-station power plants and their extensive lengths of transmission line.
Renewables are also gaining favour in industrialized countries. In the USA, national surveys show that well over half of consumers are willing to pay more for green power, and a number of power companies are now offering this option. In Europe, strong public support for clean energy is causing the renewables market to expand rapidly. In 1997, the European Commission released a white paper on renewable sources of energy, in which it noted that renewables are unevenly and insufficiently exploited in the European Union.

Different scenarios show the contribution of renewables by 2010 to range from 9.9% to 12.5%, but a goal of 12% renewables share (“an ambitious but realistic objective”) was set, to be achieved through the installation of one million PV roofs, 15,000 MW of wind and 1,000 MW of biomass energy. The current 6% share includes large-scale hydro, which will not expand for environmental reasons.  Growth is expected from biomass, followed by 40 GW of wind and 100 million square metres of solar thermal collectors.  Photovoltaics will grow up 3 GWp, geothermal by 1 GWe and heat pumps by 2.5 GWth.  Total capital investment to achieve the 12% target will be 165 billion ECU (1997-2010), but it would create up to 900,000 new jobs and drop CO2 emissions by 402 million tonnes/a.

Contributing less than 6% to the EU’s energy consumption, it called for a joint effort to increase this level for export potential and to address climate change.  More than half of Europe’s energy is imported, and will rise to 70% by 2020 without action.  The European Wind Energy Association estimates up to 320,000 jobs would be created if 40 GW of wind power is installed, the PV Industry Association says it would create 100,000 jobs if 3 GWp is met, the Solar Industry Federation estimates 250,000 jobs under its market objective, and another 350,000 jobs could be created to meet the export market. The white paper proposes a number of tax incentives and other fiscal measures to encourage investments in renewable energies, and measures to encourage passive solar.  “The overall objective of doubling the current share of renewables to 12% by 2010 can be realistically achieved,” it concludes, and the contribution of renewables to electricity generation could grow from 14% to more than 23% by 2010 if appropriate measures are instituted.

Job creation is one of the most important features related to the development of renewable energy sources. The employment potential of renewables can be estimated according to the following data:

While it is extremely difficult to quantify the external costs of such pollution, and some simply cannot be quantified, several studies show them to be substantial. For example, a German study concluded that the external costs (excluding global warming) of electricity generated from fossil-fuel plants are in the range of 2.4-5.5 US c/kWh, while those from nuclear power plants are 6.1-3.1 c/kWh. According to the another study sulphur dioxide from US coal burning plants is costing U.S. citizens USD 82 billion per year in additional health costs. Reduced crop yields caused by air pollution is costing US farmers USD 7.5 billion per year. What is important on these US figures is the fact that US citizens are actually paying between 109 billion and 260 billion dollars yearly in hidden energy costs. In other countries similar patterns can also be found. Had external economic effects been included in the market allocation process, renewable technologies would be in a far better position to compete with fossil fuels, and there might already have been a substantial shift to the penetration of renewable in the market.

ENERGY SUBSIDIES
Many governments are heavily subsidising the energy industries. It is interesting to note that the energy technologies with the worst health and environmental impacts usually receive the most government money. The worst polluters, nuclear and combustion technologies, in the U.S. alone receive 90% of the government money. The renewable energy technologies, which offer little or no side effects, receive the least government support. Solar technologies (both PV and thermal together) receive in the USA only 3% of the government money. At the bottom of the list is conservation with 2% of the subsidy dollars. And there is not much difference in other countries of the world. This is amazing since renewables and energy savings offer relief from our energy problems and has no environmental side effects. Something is really wrong here.

MILITARY
World’s dependence on imported oil requires that military will keep the international supply lines open. The U.S. military is spending between 14.6 and 54 billion dollars yearly just defending the oil supplies coming from the Persian Gulf. On the low side, the National Defence Council places the Persian Gulf military cost at 14.6 billion. On the high side, the estimate of 54 billion is made by the Rocky Mountain Institute. There are also other hidden national security costs. One of these is military aid to oil producing nations. Another is diplomatic and foreign policy decisions made on the basis of imported oil.

RADIOACTIVE WASTE
The major problem associated with nuclear power is, “What do we do with the radioactive waste?” To date, no one has a viable disposal solution for the thousands of tonnes of high level radioactive waste nuclear power plants generate. This problem is made more severe because it is a long term problem. For example, plutonium (Pu239) has a radioactive half-life of 24,400 years and is environmentally dangerous for over several hundred thousands years. We are making nuclear decisions now that will affect our planet, and all life forms on it, for millennia in the future. The World Watch Institute estimates the disposal costs of nuclear waste at between 1.44 and 8.61 billion dollars per year. Radioactive waste disposal is not actually disposal, but containment. We will have to deal with high level waste for thousands of years. We now have no method of actually disposing of high level waste. We simply store it and hope our children can figure out a safe way to deal with it. This estimate doesn’t include the cost of nuclear accidents. What does a “Chernobyl or Three Mile Island” cost to clean up?

Town Pripjat (population 30.000 before nuclear accident happened in Chernobyl in 1986) is now uninhabited and closed due to radioactive contamination.

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