Energy Systems Evolution, a Disruption of the Status Quo

Chidi Elendu

Renewable energy is derived from the earth’s natural resources, which are not finite or exhaustible, but can be replenished at a reasonable rate as it is being consumed, either naturally or by other recurring processes. It can also be referred to as any energy that can be derived from biological materials or materials of plant and animal origin and can be easily replaced or replenished as they are being used up. For example, Biomass, Bio gasolines/ Biodiesel and Biogas. It can also be referred to as clean energy. However, some renewable energy such as Biogas can be derived from biodegradable wastes, (generated as a result of human activities), which are subjected to some chemical process (Anaerobic Digestion).

It is important to state that most renewable energy derived from natural resources such as solar, wind, hydrodynamic, Geothermal, etc are mostly derived as electric energy/electricity. This is because most of the natural forms in which these energy sources exist are either as heat or kinetic energy, which cannot be easily stored to be used later. They are therefore converted into electric energy which can be easily stored and can be easily converted other form of energy. Other renewable energy sources like Biomass, Bio-gasolines and Biogas are usually derived in the form of chemical energy which can be easily converted to other forms of energy.

Fossil fuels on the other hand are fuels mainly composed of hydrocarbons, which are formed from the remains of dead plants and animals, which have been buried and laid up in the earth’s crust for over millions of years, and have lost a great amount of moisture due to heat and pressure. Such fossil fuels include coal, crude oil and natural gas. Fossil fuels are Non- Renewable energy sources.
This is due to the fact that they cannot be replenished at a similar rate at which they are being consumed. Recall that fossil fuels were formed at the earth’s crust over millions of years of accumulation of dead plants and animals, followed by exposure to heat and pressure and consequent dehydration. This is a very sluggish process when it takes place naturally. Fossil fuels are said to be non- renewable because the process that leads to their formation is very slow and takes millions of years, hence a significant amount cannot be formed within a finite amount of time in a human time scale.

There are various kinds of renewable energy with their several advantages, challenges, availability/abundance and ease of exploitation. Various Renewable Energy sources are described below:

Solar Energy: This is the energy derived from the sun. This energy exists and can be exploited in the form of heat energy from the sun and the Photons (electric charge or energy) being released by the Ultraviolet light emitted from the sun. Various photovoltaic cells popularly known as solar cells or solar panels have been developed to trap and convert the energy in the ultra violet light of the sun directly into electricity. This electricity is normally in the form of direct current and is usually stored in batteries and used anytime it is needed.
Scientists have also developed solar thermal power plants which have made it possible to absorb and convert the heat from the sun into electricity. Here some heat exchange mechanism is used to trap and concentrate (increase) the heat from the sun, while the heat is used to boil water, producing steam in the process. The steam so produced is used to turn a steam turbine which drives alternators, thereby producing electricity. The electricity produced by this method is the alternating current. Solar energy can also be used in house heating/ warming, home water heating, kitchen cooking as solar stove, etc.

The sun is always available as the sun will keep shinning. It is also very abundant especially in most tropical climate like that of Nigeria and most African countries. Therefore, utilising the free energy from the sun will be beneficial as it is clean and its exploitation does not lead to serious pollution problems. However, certain challenges associated with the exploitation of solar energy ought to be considered as well.

They include the ease of exploitation, costs of solar panels, inverters, batteries and cost of building solar thermal power plants. Also, the sun does not shine at night. However, batteries are used to store excess energy during the day and used in the night when there is no sun, though with the use of inverters. Also, scientists are continually conducting research to develop solar panels and other accessories that will be more affordable.

Wind Energy: It is the energy derived from the wind. It is trapped mostly in the form of kinetic energy. Here, a wind turbine is developed to trap and convert the kinetic energy of the wind into electricity, using the aerodynamic force from the rotor blades of the turbine. The wind turbine is designed in such a way that the wind hit the blades of the turbine at a certain angle to enable them rotate freely. The turbine has an alternator adapted into it and this alternator rotates as the blades of the turbine rotates, thereby producing electricity.

To generate a large scale electricity, wind turbines of high capacities are installed in large numbers in a given place called wind power plants. There are various ways through which wind energy can be exploited using the wind turbines. They include the Inland, Coastal and Offshore wind turbines. Inland wind turbine system are the wind turbines installed on land away from the ocean or coastal regions. Coastal wind turbine is the wind turbine designed and installed within the coasts or shores of oceans due to the abundance of wind at the ocean coast. Offshore wind turbines are the ones designed and installed in the oceans in order to exploit huge abundance of wind energy within the ocean region.

Hydrodynamic Energy: This is the energy derived from water resources like rivers. The kinetic energy of flowing water is trapped and converted into electricity, through the means of turbines. Here, a Dam is constructed across a water or river course, in such a way as to increase the speed of water flow. Turbines are installed in the Dam with water flowing at a higher speed. The turbines are turned by the pressure of the water flowing through the dam. The rotating turbines are linked or connected to alternators which rotates as the turbine rotates, thereby producing electricity.

Geothermal Energy: It is the form of energy that is derived from the heat from the earth’s crust or subsurface of the earth. This energy is usually trapped and converted into electricity through the use of water or steam. The heat in the earth’s crust is contained or generated in the rocks or fluids beneath the earth’s crust and from current radioactive decay of materials in the earth’s crust. Geothermal energy can be captured and harnessed for cooking, bathing, space heating, electricity, etc. Two or more holes are drilled into the earth’s crust. Water is pumped into the earth’s crust through one hole and the resultant steam is collected from the second hole. The steam which reaches the earth’s surface at a very high temperature and pressure is further converted into electricity using a steam turbine. Geothermal heating is currently being used in about 70 countries, while Geothermal Electricity is being used in about 26 countries of the world.

Biomass Energy: This is the form of Renewable energy derived from organic materials in order to generate electricity or heat. Examples of such organic materials include: wood, energy crops, waste from forests, farms, municipal solid waste, households, animal wastes, etc. Biomass contains stored chemical energy which can be easily converted to heat or electricity.
Biomass can be used directly as a fuel hence; it can be referred to as Biofuel. Biomass seem to be the oldest form of energy being utilised in our society, as people have been making use of fire wood to make heat for cooking and other reasons including house warming, before the advent of technology and the exploitation and use of fossil fuels.

• Elendu is a Lagos-based Engineer

Apart from the Biomass sources used directly as fuels, some sources need to pass through some processes before they can be used. These sources are the Bio- Gasolines/Bio- Diesels and Biogas. The Biomass materials are subjected to the chemical process of fermentation or anaerobic digestion to generate either Bio-gasoline, Biodiesel or Biogas.

The exploration and exploitation of fossil fuels has played a great role in the energy sector and has made a great impact in the economy of many nations and the world generally. It has also contributed immensely in the technological advancement seen in the world today. So many things that were impossible or very difficult, especially in the electricity or power sector and the transportation sector has been made easy, due to the use of fossil fuels. The advent of petroleum had reduced the rate at which coal is used for energy generation in many countries.

The exploitation of fossil fuels however, has brought with it many adverse effects. It has introduced the release of various kinds of wastes which are hazardous to man and the environment, into the planet. Most of these wastes are in the form of gases which are toxic to man and his environment. Most of these gases are referred to as Air pollutants while others are referred to as Greenhouse Gases (GHG) and Ozone Depleting Substances (ODS). Air pollutants adversely affects man directly when inhaled while greenhouse gases GHG affect the environment causing damage to the natural environment, thereby making the environment unconducive for human existence. Ozone depleting substances ODS are such gases that are inactive and cannot react or be broken down at the lower atmosphere, but reacts with the collection of ozone at the upper atmosphere (Stratosphere), damaging the ozone layer thereby allowing the dangerous and harmful ultraviolet rays of the sun to reach the earth’s surface.

Examples of these air pollutants include: Carbon (II) Oxide CO, Nitrogen Oxides NOx, Sulphur Oxides SOx, Formaldehyde, Volatile Organic Compounds VOCs, Particulate matter PM, etc. Greenhouse gases are Carbon (IV) Oxide (Carbon Dioxide) CO2, Methane CH4, Nitrogen (I) Oxide (Nitrous oxide) N2O, Hydrofluorocarbons HFCs, Perfluorocarbons PFCs, Sulphur hexafluoride SF6, Nitrogen trifluoride NF3, etc. Ozone depleting substances are mainly the Chlorofluoro carbons CFCs. Carbon dioxide from the burning of fossil fuels is the largest single source of greenhouse gases emissions from human activities. The supply and use of fossil fuels accounts for about 80 percent of mankind’s carbon dioxide (CO2) emissions, a significant quantity of methane CH4 and Nitrous oxide N2O. In summary, the main contributing sectors to human activity greenhouse gases emissions are electricity and heat (24.9%), industry (14.7%), transportation (14.3%) and Agriculture (13.8%).
Amongst the numerous problems created by the use of fossil fuels, the one with the greatest negative impact is that of Global warming and Climate Change.

Currently, climate change and its impacts on the environment and man is one of the greatest challenge faced by man today, as it would determine if life would continue to exist on earth in the nearest future. Global warming can be referred to as the rise in the global temperatures due to the absorption and retention of heat from the sun by greenhouse gases in the atmosphere. Increase in the concentration of greenhouse gases in the atmosphere followed by increase in atmospheric temperature has become a great threat to the environment of man as the major factor that affects the climate is temperature of the earth’s surface. Climate change is the change in the climate characteristics or conditions, such as temperature, humidity, rainfall, wind patterns and severe weather events over a long period of time. Climate change is caused by the increase in the rate of Global warming.

Scientists have reported that the global average temperature has increased with additional 1.50C, leading to the change in climate and the various adverse effects being observed in different parts of the world today. The climate has already changed and the impacts are much noticeable. Governments of the nations across the world are only being urged to adopt measures to enable their citizens adapt to the adverse effects caused by climate change, and to adopt methods of energy or power generation that would not add to the increase in the global temperatures. Some of the climate change impact on the environment include changes in:

Temperature, which leads to increase in energy demand for heating or cooling, worsening of air quality, water shortages, higher food prices, disruption of Hydro-electric output, distress migration from rural areas, etc.
Precipitation(Rainfall/snow), which leads to increased risk of flooding, landslides, more intense flooding, disruption to livelihoods and urban economies, damage to homes and businesses, damage to infrastructure, interruption of food supply networks, distress migration from rural and coastal areas.
Sea-level rise, which cause coastal flooding, salination of water sources and reduced income from agriculture and tourism.

Biological changes lead to extended vector habitats with impacts on health and agriculture, more favourable breeding grounds for pathogens, loss of biodiversity, etc. all these leads to higher health hazards.
It is however important to note that climate change with its associated impacts on the environment and man is mainly caused by the presence and increase in the amount of greenhouse gases in the atmosphere, and these gases are released as a result of the exploitation and use of fossil fuels. Scientists have also predicted that if the global temperature rises up to +20C, the impact of climate change will be so enormous and unbearable there will be extreme weather conditions, heat waves, melting of ice and glaciers at mountain tops, melting of ice in the oceans, extreme rise in ocean or sea level, which would lead to many coastal cities being buried completely under water and extreme flooding occurrence in cities along water or river courses.

Due to the fact that the prolonged and continuous/ continual use of fossil fuel-based energy sources has caused and will continue to cause great harm to the environment and to man, there is a need to address the issue when it can still be managed. The availability and use of renewable energy sources provides solution to the problem. All renewable energy sources are clean. Even the renewable energy sources that are based on Biomass or Biofuels are clean because they burn with a much higher combustion efficiency, unlike the fossil fuel-based energy sources. Moreover, most renewable energy sources such as Solar, Wind, Geothermal and Hydrodynamic Energy, does not require any form of combustion to utilize them.

Renewable energy can be used as a complement to the fossil fuels by developing a proper energy mix. Here the amount of power plants generating electricity using fossil fuels can be reduced, while a reasonable percentage of electricity would be generated by harnessing more efficiently, the abundant renewable energy like the Hydrodynamic, Solar, Wind and Geothermal energy. Power plants should be developed to operate with solar and wind energy, to provide power during the day especially on sunny days and during periods of high wind speed. Hydrodynamic and Geothermal energy power plants should be developed to provide power during the night and to serve as standby power sources during solar and wind energy downtimes. Also, idle energy from the solar and wind energy power plants should be stored up and used when needed.

It may not be so easy to totally eliminate the use of fossil fuels at the moment, but its usage can be reduced or minimised greatly. If about 70 per cent of the power plants using fossil fuels globally is replaced by renewable energy power plants (solar, wind, hydrodynamic and geothermal), there would be a significant reduction in the amount of greenhouse gases (GHG) being emitted into the atmosphere, hence a lower risk of continual climate change and its impacts. Also, most Automobile and Aeronautic engines can be designed to use the biofuels such as ethanol and biogas. These biofuels has been proved to burn with higher combustion efficiency the fossil fuels. This would reduce the amounts of air pollutants and greenhouse gases being released into the atmosphere and their climate change impacts. Recall that the main problem with fossil fuels usage is that of incomplete combustion which results in pollution.

In as much as renewable energy can be used as a complement to fossil fuels, there is a possibility of completely replacing fossil fuels with renewable energy. This is because targeted efforts can be made to completely replace all existing fossil fuel power plants with renewable energy power plants. This process can be taken gradually but consciously and continuously until a complete or total replacement is achieved. Also, for the transportation industry which requires fuels to operate, the biofuels can be used to totally replace the fossil fuels. The design and development of electric cars is gradually gaining grounds in the world today.

Renewable energy sources like solar and wind energy can be harnessed to develop these electric cars solar and wind energy are easily converted to electricity.
Statistics shows that in the year 2018, renewable energy contributed 16 per cent of electricity generation globally. Also, some countries that have advanced in technology and in renewable energy exploitation have set deadlines to completely stop the use of petroleum and fossil fuels as an energy source and if they must be used, it must only be used with a carbon capture device or plant attached to such fossil fuel energy plants. One of such countries is Norway.

In conclusion, the continuous or continual exploitation and use of fossil fuels over the years has led to tremendous increase in the concentration or amounts of greenhouse gases (GHG) in the atmosphere, leading to global warming and the resultant climate change and its impacts on the environment and man. These amounts of greenhouse gases in the atmosphere are sure to keep increasing if we continue to use more fossil fuels in energy generation. Hence the call to reduce the rate at which fossil fuels are being utilised and to ultimately stop its use as an energy source. The use of renewable energy as a substitute and a complete replacement for fossil fuels provides solution to the numerous problems caused by the use of fossil fuels. Prolonged usage of renewable energy would help reduce the impact of climate change already caused by fossil fuel energy generation. Over time, it would be possible to recreate the nature and bring our environment close to its original natural state before the advent of fossil fuels and petroleum. Thus, we have the opportunity to save our planet and humankind from extinction.
Elendu is a Lagos-based Engineer