Renewable Energy

The History of Renewable Energy and Renewable Energy Today

Environmental concern is getting more prominent globally day by day. To ensure a stable future for both the planet, and humanity, renewable energy has become an effective and pressing solution. But the idea of renewable energy is not new. The oldest form of renewable energy was the conversion of biomass into fuel fires that have been used since 790,000 years ago. Then there came the use of wind energy to propel ships in water. There are some other energy sources that are also considered as the primary sources of renewable energy such as water energy, human labor, and animal power.

In 1900, the United States was solely dependent on oil and natural gas. But in contemporary times, the scenario is changing as solar energy, hydroelectricity, wind energy and other alternatives are joining the energy mix, providing more of the US's energy needs.

Biomass is produced from animal and plant derived materials. It is mostly composed of carbon and there are some other elements such as hydrogen, oxygen, and nitrogen. Biomass can directly be used for combustion and can also be used in the form of biofuel. Thermal, chemical or biochemical methods can be applied to biomass to make biofuel. Although burning biomass does create carbon emissions that are the primary cause of anthropogenic climate change, it is still the main source of energy in many of the developing countries.

Hydroelectricity is generated by harnessing gravity and the natural flow of water. Water precipitates from the rivers and oceans to fall down as rain. This water flow creates kinetic energy: this energy is then converted to electric energy by hydroelectric power plants. To create efficient energy from water flow, a dam is created in the flow path of water. A turbine and a generator are set and dammed water is forced to flow through the turbines. By absorbing the kinetic energy from the water, the turbine starts to rotate and this rotation creates energy that is stored as electricity in a generator. Though it is an emissions free process, it still possesses some problems. Dams which iare used to harness the waters kinetic energy can affect the natural river system; creating hazards and obstructions to the migratory fish, and the wildlife in general of the river habitat.

Solar energy is an unlimited source of energy provided by the radiation of the Sun. There are two types of solar energy systems - active solar energy systems and passive solar energy systems. Active solar energy systems convert solar energy into usable energy, while passive solar systems are used to gather, store and distribute electricity - to maintain a continuous supply.

By using the power of wind, we can get electrical power from wind turbines, mechanical energy from windmills, and water elevation by using wind pumps. Wind turbines are made by attaching a rotor turbine to a large tower. The rotor consists of two or three blade type propellers. When the wind blows, it spins the rotors that create power and the energy is then transferred to a generator. As with solar, this energy can also be stored in batteries. Wind energy is getting more popular day by day, as it is a completely emission free energy solution, whereas energy from oil and coal creates phenomenal amounts of greenhouse gas emissions worldwide every year.

Helium 3

Currently, the world as a whole is running primarily on oil based energy. Our transportation, lifestyles and work are at present dependent on oil, gas and / or coal. But these resources are not unlimited. Reports show that reserves are most likely running out rapidly; especially global oil reserves. Not to mention the phenomenal amount of “locked up” greenhouse gasses which will be released into the planet's atmosphere if we burn every last drop. There is a current real, less publicized energy crisis, and if we do not find an energy solution, our future may become bleak (although we always have the option of practising rudimentary terraforming - which is something we are currently doing inadvertently - to reduce the impact of anthropogenic climate change). One of the possible recently proposed solutions is Helium-3.

Currently we are getting a huge amount of energy from nuclear fission reactions, unfortunately, it is not the best possible solution because the radioactive residue of this process can be a dangerous environmental contaminant for many thousands of years. Whereas nuclear fusion power (as opposed to fission) can be a real blessing in meeting the energy needs of humanity. Nuclear fusion reaction occurs in the sun producing heat and light on an unimaginable scale. The sun actually emits helium-3, which we can use for nuclear fusion reaction. The Earth’s magnetic fields do not allow helium-3 to come to the Earth's surface. As there is no atmosphere on the Moon, helium-3 is slowly but surely gathering on the Moon’s surface - and has been doing so for millions of years.

The moon is literally covered in helium-3, and many scientists today are now calling for humanity to harvest and use this phenomenal energy source. The sunlit side of the Moon contains 1.4 to 15 parts-per-billion of helium-3, while the dark side of the Moon contains 50 ppb. The energy that we can harness from helium-3 is unimaginably huge. Just 25 tons of helium-3 can power the USA for an entire year. Russia is currently the only nation on Earth that has its eyes on the Moon's helium-3 supplies. The Russians are planning to construct a moon base by 2015; with the goal of beginning to harvest the Moon's helium-3 by 2020. The USA, China, India and Germany are also considering their options.

There are two types of nuclear fusion reactions possible with helium-3. The reaction between deuterium and He-3 results in one proton, while the reaction between two molecules of helium-3 produces two protons. As we can see there are no neutron emissions, so it is quite safe and very clean. In traditional nuclear fission reaction, the emitted neutron creates heat energy. This heat energy rotates a turbine by producing steam. But, in the case of this helium-3 fusion reaction, there is no turbine required as we are harnessing the energy directly from proton.

Helium-3 powered nuclear fusion is a truly next generation, and revolutionary, clean energy technology. Not only would widespread helium-3 use solve Earth's energy crisis - it will also make the first nation / company / person to begin harvesting it from the Moon incredibly rich.

Though it can solve our energy problem it is costly. The main problem is the density of He-3 in the lunar regolith: to get just one ton of helium-3 almost 150 tons of lunar regolith would need to be processed. Helium-3 is extremely rare on Earth; the only viable source of Helium-3 is the Moon. The transportation of this element from the Moon to Earth is also very expensive; however due to the enormous amount of energy just one tonne of Helium-3 can generate, a o Helium-3 mining operation would still be very financially viable and indeed rewarding.

Space Based Solar Power

Currently, we are mainly dependent on coal and oil based resources: fossil fuels. Energy consumption worldwide is projected to double by the year 2030, and will quadruple (at least) by the end of this century. We are continuously using up our reserves and renewable, clean energy is the only viable option for humanity's energy future. So to help meet our energy needs, and for the sake of our environment, the idea of solar energy has become prominent.

At present there are two types of solar power- Earth based solar power and space based solar power (SBSP). Earth based solar power has some drawbacks: there is not a constant energy supply because the sun gives light and heat only during the daytime. Also we have to depend on local environmental conditions such as a lack of cloud cover, to harness the free energy from the Sun. So space based solar power has become the latest implementation of a high tech solar powered energy solution.

In space based solar power systems, energy is collected from the sunlight in Space. It’s actually been in use since the early 1970’s on various satellites and probes. The key difference between SBSP and conventional land bound solar power, is that SBSP harvest energy as an orbiting satellite, whereas conventional solar power systems gather luminal energy through solar panels on the Earth. SBSP systems have a higher energy collection rate due to no atmospheric interference and a longer collection period because SBSP systems are bathed in continuous light from our Sun.

The SBSP system has three parts- the conversion tool, the transmission tool and a receiving station. The conversion tool converts the light directly into microwave energy. This conversion can occur by two methods- photovoltaic and solar dynamic. Photovoltaic converts photons into electrical power by semiconductor cell, and solar dynamic concentrates the light on a boiler by using a mirror. Solar dynamic can reduce the energy being converted, which is why photovoltaics are primarily used for conversion. The transmission tool consists of large antenna that transmits this microwave energy to a receiving station on the Earth's surface. The Earth based receiving station is a larger antenna that is known as a rectenna.

In Earth based solar power systems, the sunlight energy hitting the panel gets filtrated by clouds, the atmosphere and air particles. So we do not get intense sunlight. By contrast, a SBSP is receiving 24 hour sunlight. SBSP energy can be directly transmitted to any land based station where it is needed.

Though SBSP is more efficient, the cost is still very high for electricity generation. The maintenance cost is also very high because to solve any mechanical problems on the satellite mounted solar panel, astronauts need to go up from the Earth. Also it can cause orbital debris and a large area is also needed on the Earth to house a microwave energy receiving station.

Nevertheless, the demerits of SBSP are not acute compared to the abundant clean energy this solution provides. As we know, England dominated the world by taking possession of coal, the USA is currently dominating the world with their oil resources, perhaps those visionaries who harness and control space based solar energy will be the future leaders of the world.

Hydrogen Fuel

Fossil fuel is running out and as we know, our transportation is solely dependent on fossil fuels (cars, planes etc). Hydrogen fuel replacing carbon fuel is a viable option for future transportation clean energy needs. Hydrogen fuel is made from hydrogen- the lightest fuel on earth. The Hydrogen atom has just one neutron and one proton; it is also the most common element on this planet. We can extract hydrogen easily as it is bonded to almost 90% of the earth’s matter. Using hydrogen as the foundation of vehicles' propulsion systems means that the only emission is water.

This fuel can play a great role in the future energy needs of humanity. The rate of oil discoveries has been decreasing steadily over last few decades. In turn the price of fuel is constantly increasing day by day. If hydrogen fuel can be produced on a large scale, it can take the place of oil and the constantly increasing fuel price can be controlled. Obviously, there may be powerful vested interests against the widespread use of Hydrogen fuel. In a perfect world we would already be using it.

Hydrogen is actually an energy carrier and not a source. So it needs to be produced by another energy supply. There are two key methods of Hydrogen production- steam reforming and electrolysis. Steam reforming means the production of hydrogen from hydrocarbons and water. Electrolysis is the process whereby water is dissipated into hydrogen and oxygen by means of electricity. This electricity can come from renewable energy sources, nuclear power or fossil fuel. The cost of production by harnessing power from fossil fuel is not economically viable. But by using renewable sources like wind energy, Hydrogen production could be immensely profitable, as well as ensuring all vehicles on Earth are powered by clean energy. If we could store wind energy in hydrogen this would also be a great asset.

The main implementation of hydrogen fuel is in private transport vehicles such as cars. Currently vehicle companies use fuel cells or internal combustion engines to store hydrogen. Hydrogen can be stored as a compressed gas, a liquid or in a solid state. As hydrogen contains electric power, so to use this energy directly existing vehicles need to be modified. Some heartening news is that the next generation of vehicles now have the built in capacity to use hydrogen fuel. This fuel can be used to generate electricity.

The safety of the hydrogen processing plant itself is very important. If any leak occurs in the plant it will spread out in a huge amount, because this is the lightest element of all known matter. Hydrogen burns more than natural gas and it cannot be traced. So if leakage occurs it could be difficult to find out where the problem has occurred. Researchers have created hydrogen sensors such as “Smart Paint”; this sensor can be painted on all the plant's surfaces, so leakage tracing is significantly enhanced.

It is undoubtedly true that hydrogen fuel is a better solution for energy and the propulsion systems of private vehicles. Countries like the USA, Russia, Japan and Germany are conducting research to make hydrogen fuel economically accessible. The USA actually has a plan to convert its fossil fuel vehicle infrastructure into hydrogen fueled eco-friendly vehicles by the year 2020.

Combined Heat and Power

In conventional energy generation, a huge amount of power is wasted due to the lack of advanced technology. This conventional method is known as Separate Heat and Power (SHP). So to use as much energy as possible from energy generation, researchers developed a new idea: this idea is named Combined Heat and Power (CHP) - also known as cogeneration. In traditional power processing, we just capture electricity but we cannot capture a huge amount of heat energy. CHP's prime advantage is we can capture both heat and electricity.

The heat recycling process was invented by Thomas Edison in 1882. Cogeneration is now gaining popularity in the world for its energy efficiency factor. The USA is currently producing 8% of its electricity by this process and they are also planning to make it 20% by just using the wasted thermal energy of factories and industries. Denmark is utilizing this process greatly as they are producing 55% of their national power consumption with cogeneration.

There are different types of CHP plants. There are steam turbine, combined cycle, biofuel engine, gas engine, gas turbine CHP etc. High temperature heat supplied by CHP is being used to rotate a turbine and it creates mechanical energy which provides us electricity. Low temperature heat is used to heat the water and space.

The future of our conventional energy generation from fossil fuels and so so on is quite bleak due to the limitations of our resources. So to solve this problem, newer energy sources are needed as well as increasing the efficiency of currently existing energy generation technology. CHP is meeting this need. Germany is planning to obtain from 12.5% to 25% of its power from cogeneration by the year of 2020. The UK has a target of reducing its carbon emission by 60% by the year 2050; they are also relying greatly on the use of CHP. The UK also met 15% of their national power demand from this method in 2010. IEA reports show that, by using this process France, UK, Germany, Italy could double their power efficiency with their existing resources by the year 2030. This process can also be used in motor vehicles so that CO2 emissions would decrease gradually.

If the successful implementation of this project could be established, then the cost of fuel energy would also come down. Also the commercial user can use this plant in their industries. Both electrical and thermal energy can be obtained by using CHP. The cost effectiveness is the main factor for using this. Before using this cogeneration process, the USA had a power efficiency of only 34% in 1960. That means huge energy wastage was occurring at that time. An interesting fact is that the energy that was wasted by USA is equal to the total power capacity of Japan.

In obtaining energy by CHP, the maintenance and transportation cost is also quite high. But considering the fact of cleaner energy and also if we take into consideration the energy production rate compared to more traditional energy generation methods, CHP power is a method of energy generation which has an important role to play in a clean energy future.

Geothermal energy

At the start of the 20th century, the concern for new energy has become prominent. Humanity has started to search for energy in every aspect of Earth. The concern for the environment has become a key priority in this searching. Though geothermal energy production is not significant compared to the world’s total power consumption, it can still be a safe and clean energy solution when it is utilized.

The idea of geothermal energy has come from ancient times. From Paleolithic times, hot springs have been using for bathing purposes. The commercial value of geothermal energy was established by commercializing these geothermal baths since the first century AD. The industrial use of geothermal energy began in 1827, with the use of this energy into power generation beginning in 1904. Geothermal heat pumps were made in 1940 by using the theory of Lord Kelvin’s heat pump. This technology became much more widespread from 1960 onwards.

Earth’s upper surface contains a temperature of 50° to 60°F. A geothermal pump is used for heating and cooling a building. This device has three parts- heat pump, ductwork and heat exchanger.

An international organization named the International GEOTHERMAL Association (IGA) is working with 65 countries to develop this method. Research continues under the funding of IGA. They are also cooperating with the International Renewable Energy Alliance (REN). Reports from IGA show that, about 10,714 MW of power is produced now in 24 countries all over the world. The next plan of IGA is to make another 18,500 MW by the year 2015. The USA is the leading geothermal power producer of the world. The US produces 29% of the world’s geothermal energy and 0.3% of their national electricity production. Philippine is already producing 27%, Kenya is 12.4% and Costa Rica is producing 11.4% of their national demand. Japan, Iran, Russia are also high on the list.

Reports from the Geothermal Energy Association (GEA) show that Kenya is constructing 1000 MW geothermal infrastructure, Indonesia will have the capability of 2GW by the year 2018. This report demonstrates the growing worldwide adoption of Geothermal energy as a clean, renewable energy source.

This mechanism can be a better alternative of electric heating. Compared to coal and wind farms, geothermal plant need less land as they use only 3.5 square kilometres of land for the production of approximately 1GW electricity. Nuclear, coal and oil production need almost 1000 litres of water per MW-hour whereas a geothermal plant needs only 20 litres for the same amount of production. Geothermal plants can also be used widely for drying crops, heating water at fish farms, milk pasteurization and in greenhouse plants.

Geothermal plants do have some environmental problems. The hot fluid from geothermal plants contain mercury, boron, arsenic and antimony. When these elements are directly released to the environment, it can cause problems to the local environment, and global, environment and ecoystem. The CO2 emission rates of geothermal power plants are 122 kg per kilowatt-hour; but a small fraction compared to conventional fossil fuel power generation. As far as safe and clean energy is concerned, geothermal power could play an important role - as part of the solution.

Waste To Energy

In our daily work and lives, we are regularly creating garbage and this is called Municipal solid waste (MSW). Industries are also creating waste material in their industrial process, however this is not called MSW. Radioactive, medical, agricultural wastes are some types that are not included as MSW.

This waste can be converted to electricity or heat by using Waste to Energy (WTE) power plants. This process create energy by combustion. WTE plants emit sulphur dioxide (SO2), nitrogen oxide (NO), dioxin and solid metals. New plants now built under OECD have to maintain certain criteria to control hazardous emission. This waste energy transformation is done in an incinerator. Now the modern incinerators are made in such a way that it can reduce the volume of waste by 90-95%. But the efficiency of this model is low and is 14-15%. This efficiency can be increased to 80% by using cogeneration incinerators and this can be used for heating purposes. Incinerators combined with flue gas condensation have the efficiency of 100%. Energy can also be produced without direct combustion. Efficiency can be increased by separating the corrosive materials. There are thermal and non-thermal technologies to convert waste into energy.

Every country has residual, commercial or agricultural garbage. It is clear to them that, this is not waste, this is an asset. By using WTE plants they are creating energy. From the start of this century, energy production by waste management has increased to four million metric tons each year. Japan is the leading country in WTE generation with a production capability of 40 million tons. China has a huge population and is competing with Japan. They have 50 WTE plants.

Worldwide some modern technologies such as stoker technology are being utilized in WTE operations. In a stoker power plant, biodiesel can be created by fermentation. Despite having many advantages there are also some disadvantages too. In a regular MSW, the waste contains carbon material and this material produces same amount of CO2. This means that, one ton of waste combustion would create one ton of carbon dioxide. So this is a great concern. But if one tonne of waste is stored on the ground, this could create 62 cubic meters of methane gas that would cause twice the harm than one tonne of CO2. So taking this into consideration, this plant can be called comparatively eco-friendly.

Almost half of the MSW material is biogenic such as food, cloth, wood, cardboard and paper. Waste management of these materials is not same as others. So to get energy from these resources, another way of management is needed. Researchers have developed two methods: the selective dissolution method and the manual sorting method. The first method uses mathematical-statistical models with the existing data of the material. This is called the balance method. The second method uses radiocarbon dating. Currently the balance method is used in some Australian and Danish incinerators. Demonstration shows that both of these methods have the same efficiency.

WTE technology is not a type of method that can stop carbon emission completely. This just helps to reduce the amount of CO2 also with the outcome of energy. So this could be a better answer towards our continuous environmental degradation and increasing power crisis.

Non-Fiction Science

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