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What is Alternative Energy?
In recent years, alternative energy has been the subject of intense interest and debate. Thanks to the threat of Climate Change, and the fact that average global temperatures continue to rise year after year, the drive to find forms of energy that will reduce humanity’s reliance on fossil fuels, coal, and other polluting methods has naturally intensified.
While most concepts for alternative energy are not new, it has only been in the past few decades that the issue has become pressing. And thanks to improvements in technology and production, the costs of most forms of alternative energy has been dropping while efficiency has been increasing. But just what is alternative energy, and what is the likelihood of it becoming mainstream?
Definition:
Naturally, there is some debate as to what “alternative energy” means and what it can be applied to. On the one hand, the term can refer to forms of energy that do not increase humanity’s carbon footprint. In this respect, it can include things as nuclear facilities, hydroelectric power, and even things like natural gas and “clean coal”.
On the other hand, the term is also used to refer to what are currently considered to be non-traditional methods of energy – such as solar, wind, geothermal, biomass, and other recent additions. This sort of classification rules out methods like hydroelectric, which have been around for over a century and are therefore quite common to certain regions of the world.
Another factor is that alternative energy sources are considered to be “clean”, meaning that they don’t produce harmful pollutants. As already noted, this can refer to carbon dioxide but also other emissions like carbon monoxide, sulfur dioxide, nitrogen oxide, and others. Within these parameters, nuclear energy is not considered an alternative energy source because it produces radioactive waste that is highly toxic and must be stored.
In all cases, however, the term is used to refer to forms of energy that will come to replace fossil fuels and coal as the predominant form of energy production in the coming decades.
Types of Alternative Energy:
Strictly speaking, there are many types of alternative energy. Once again, definitions become a bit of a sticking point, and the term has been used in the past to refer to any method that was considered non-mainstream at the time. But applying the term broadly to mean alternatives to coal and fossil fuels, it can include any or all of the following:
Hydroelectricity: This refers to energy generated by hydroelectric dams, where falling water (i.e. rivers or canals) are channeled through an apparatus to spin turbines and generate electricity.
A nuclear power plant, releasing hot steam as a byproduct of its slow fission process.
Nuclear Power: Energy that is produced through slow-fission reactions. Rods of uranium or other radioactive elements heat water to generate steam, which in turn spins turbines to generate electricity.
Solar Power: Energy harnessed directly from the Sun, where photovoltaic cells (usually composed of silicon substrate, and arranged in large arrays) convert the Sun’s rays directly into electrical energy. In some cases, the heat produced by sunshine is harnessed to produce electricity as well, which is known as solar-thermal power.
Wind Power: Energy generated by air flow, where large wind-turbines are spun by wind to generate electricity.
Geothermal Power: Energy generated by heat and steam produced by geological activity in the Earth’s crust. In most cases, this consists of pipes being placed in the ground above geologically active zones to channel steam through turbines, thus generating electricity.
Tidal Power: Energy generated by tidal harnesses located around shorelines. Here, the daily changes in tides causes water to flow back and forth through turbines, generating electricity that is then transferred to power stations along the shore.
Biomass: This refers to fuels that are derived from plants and biological sources – i.e. ethanol, glucose, algae, fungi, bacteria – that could replace gasoline as a fuel source.
Hydrogen: Energy derived from processes involving hydrogen gas. This can include catalytic converters, where water molecules are broken apart and reunited by electrolysis; hydrogen fuel cells, where the gas is used to power internal combustion engines or heated and used to spin turbines; or nuclear fusion, where atoms of hydrogen fuse under controlled conditions to release incredible amounts of energy.
Alternative and Renewable Energy:
In many cases, alternative sources of energy are also renewable. However, the terms are not entirely interchangeable, owing to the fact that many forms of alternative energy rely on a finite resource. For instance, nuclear power relies on uranium or other heavy elements that must be mined.
Based on the current rates of adoption, the long-term prospects for alternative energy are extremely positive. According to a 2014 reportby the International Energy Agency (IEA), photovoltaic solar power and solar thermal power will account for 27% of global demand by 2050 – making it the single largest source of energy. Similarly, a 2013 report on wind power indicated that by 2050, wind could account for up to 18% of global demand.
The Best Examples of Alternative Energy
Sources
11. Hydrogen Gas
Unlike other forms of natural gas, hydrogen is a completely clean burning fuel. Once produced, hydrogen gas cells emit only water vapor and warm air when in use.
The major issue with this form of alternative energy is that it is mostly derived from the use of natural gas and fossil fuels. As such, it could be argued that the emissions created to extract it counteract the benefits of its use.
The process of electrolysis, which is essential for the splitting of water into hydrogen and oxygen, makes this less of an issue. However, electrolysis still ranks below the previously mentioned methods for obtaining hydrogen, though research continues to make it more efficient and cost-effective.
10. Tidal Energy
While tidal energy uses the power of water to generate energy, much like with hydroelectric methods, its application actually has more in common with wind turbines in many cases.
Though it is a fairly new technology, its potential is enormous. A report produced in the United Kingdom estimated that tidal energy could meet as much as 20% of the UK’s current electricity demands.
The most common form of tidal energy generation is the use of Tidal Stream Generators. These use the kinetic energy of the ocean to power turbines,
without producing the waste of fossil fuels or being as susceptible to the elements as other forms of alternative energy.
9. Biomass Energy
Biomass energy comes in a number of forms. Burning wood has been used for thousands of years to create heat, but more recent advancements have also seen waste, such as that in landfills, and alcohol products used for similar purposes.
Focusing on burning wood, the heat generated can be equivalent to that of a central heating system. Furthermore, the costs involved tend to be lower and the amount of carbon released by this kind of fuel falls below the amount released by fossil fuels.
However, there are a number of issues that you need to consider with these systems, especially if installed in the home. Maintenance can be a factor, plus you may need to acquire permission from a local authority to install one.
8. Wind Energy
This form of energy generation has become increasingly popular in recent years. It offers much the same benefitsthat many other alternative fuel sources do in that it makes use of a renewable source and generates no waste.
Current wind energy installations power roughly twenty million homes in the United States per year and that number is growing. Most states in the nation now have some form of wind energy set-up and investment into the technology continues to grow.
Unfortunately, this form of energy generation also presents challenges. Wind turbines restrict views and may be dangerous to some forms of wildlife.
7. Geothermal Power
At its most basic, geothermal power is about extracting energy from the ground around us. It is growing increasingly popular, with the sector as a whole experiencing five percent growth in 2015.
The World Bank currently estimates that around forty countries could meet most of their power demands using geothermal power.
Much like with tidal energy, the benefits come in the lack of waste produced. It is also more reliable than many other forms of alternative energy and has enormous potential when used properly.
Again, the cost of such systems is a major contributing factor to slow uptake. We also don’t yet have enough data to find out how wave energy converters affect natural ecosystems.
3. Hydroelectric Energy
Hydroelectric methods actually are some of the earliest means of creating energy, though their use began to decline with the rise of fossil fuels. Despite this, they still account for approximately seven percent of the energy produced in the United States.
Hydroelectric energy carries with it a number of benefits. Not only is it a clean source of energy, which means it doesn’t create pollution and the myriad issues that arise from it, but it is also a renewable energy source.
Better yet, it also offers a number of secondary benefits that are not immediately apparent. The dams used in generating hydroelectric power also contribute to flood control and irrigation techniques.
2. Nuclear Power
Nuclear power is amongst the most abundant forms of alternative energy. It creates a number of direct benefits in terms of emissions and efficiency, while also boosting the economy by creating jobs in plant creation and operation.
Thirteen countries relied on nuclear power to produce at least a quarter of their electricity as of 2015 and there are currently 450 plants in operation throughout the world.
The drawback is that when something goes wrong with a nuclear power plant the potential for catastrophe exists. The situations in Chernobyl and Fukushima are examples of this.
1. Solar Power
When most people think of alternative energy sources they tend to use solar power as an example. The technology has evolved massively over the years
and is now used for large-scale energy production and power generation for single homes.
A number of countries have introduced initiatives to promote the growth of solar power. The United Kingdom’s ‘Feed-in Tariff’ is one example, as is the United States’ ‘Solar Investment Tax Credit’.
This energy source is completely renewable and the costs of installation are outweighed by the money saved in energy bills from traditional suppliers. Nevertheless, solar cells are prone to deterioration over large periods of time and are not as effective in unideal weather conditions.
In Conclusion
As the issues that result from the use of traditional fossil fuels become more prominent, alternative fuel sources like the ones mentioned here are likely to gain further importance.
Their benefits alleviate many of the problems caused by fossil fuel use, particularly when it comes to emissions. However, the advancement of some of these technologies has been slowed down due to the amount of investment needed to make them viable.
Through combining them all we may be able to positively affect issues like climate change, pollution and many others.
Please do contribute to the discussion below and let us know your thoughts on alternative energy sources in the comments section or by sharing this article on social media.
Alternative energy encompasses all those things that do not consume
fossil fuel. They are widely available and environment friendly. They
cause little or almost no pollution. There have been several
alternative energy projects running in various countries to reduce our
dependence on traditional fossil fuels. There are many impressive
options that you can take into consideration such as solar tankless
water heater reviews. Here in you will learn more about alternative
energy sources that you can take into consideration.
Advancement in technologies has brought down the cost of setting up
wind power plant. Wind energy can only be used in areas which
experience high winds which mean that it cannot be used as a source
to extract energy anywhere on earth. They sometimes create noise
disturbances and cannot be used near residential areas. These
disadvantages have made the use of wind energy to particular regions
only.
Geothermal Energy
‘Geo’ means Earth and ‘thermal’ means energy. Geothermal energy
means energy drawn or harnessed from beneath the earth. It is
completely clean and renewable. Geothermal energy has been in used
since last several years. The earth contains a molten rock called
magma. Heat is continuously produced from there. The temperature
increases about 3 degrees Celsius, for every 100 meters you go below
ground. Below, 10,000 meters the temperature is so high, that it can
be used to boil water. Water makes its way deep inside the earth and
hot rock boils that water. The boiling water then produces steam which
is captured by geothermal heat pumps. The steam turns the turbines
which in turn activates generators. Read more about working of
Geothermal energy here.
Geothermal energy can be found anywhere on the earth. Most
countries tap this energy to generate electricity, using thermal mass
flowmeters, and power millions of homes. The areas which have high
underground temperatures are the ones which are the ones which are
prone to earthquakes and volcanoes. The United States produces more
Geothermal electricity than any other country in the world. Most hot
water geothermal reservoirs are located in the western states, Alaska,
and Hawaii. Geothermal energy is totally renewable as earth will
continue to produce heat as long as we are all are here. If these
resources are tapped and are utilized effectively, they can provide
solution to the world’s power problems.
Geothermal energy produces no pollution, reduces our alliance on
fossil fuels. It also results in significant cost savings as no fuel is
required to harness energy from beneath the earth. These advantages
make geothermal energy as one the best alternative energy source.
But, geothermal has its downsides too. It is suitable to particular region
and cannot be harnessed everywhere. The earth may release some
harmful gases while releasing the heat which may prove adverse from
mankind. Also, the areas where this energy is harnessed are prone to
earthquakes and volcanoes. Apart from that, setting up of geothermal
power stations requires huge installation cost. Here are some pros and
cons of geothermal energy.
Hydroelectric Energy
Solar energy is produced by sun and wind energy is produced by
moving of winds. The heat caused by sun drives the wind. The
movement of winds is then captured by wind turbines. Both wind and
sun cause water to evaporate. The water vapor then turns into rain or
snow and flows down to sea or oceans through rivers or streams. The
energy of the moving water can then be captured and called as
hydroelectric power. Hydroelectric power stations capture the kinetic
energy of moving water and give mechanical energy to turbines. The
moving turbines then convert mechanical energy into electrical energy
through generators. Dams around the world have been built for this
purpose only. Hydropower is the largest producer of alternative energy
in the world.
There are different types of hydropower plants. The selection of
hydropower plant depends on many volume and flow of water.
Hydropower is renewable, constant, predictable and controllable
source of energy. They emit no greenhouse gases and are environment
friendly. On the negative side, they may cause adverse effect on
aquatic life, reduce flow of water which may affect agriculture, require
huge costs to build and may cause havoc if they get breakdown.
Biomass Energy
This is the process by which an alternative energy is generated
through conversion of biological materials and wastes into forms that
can be used as energy sources for heating, power generation and
transportation. Those carbon based substances or materials converted
over a long period of time to fossil fuels are not regarded as biomass.
However, in their original state they are regarded as biomass. This is
because of the separation of the carbon they previously contained
and are much more predictable than wave energy. Learn more about
the tidal energy here.
Hydrogen Energy
Hydrogen is the most abundant element available on earth but it is
rarely alone. Even water contains two third of hydrogen. It is usually
available with other elements and have to separated before we can
make use of it. Hydrogen has tremendous potential and can be used to
power up homes, vehicles and even space rockets. It takes a lot of
energy to separate hydrogen from other elements and therefore it
proves to quite expensive to extract it. Take a close look at hydrogen
energy and see how it works.
The main benefit of hydrogen energy is that it is clean source of fuel
and does not leave any waste elements behind except water. There are
no harmful emissions and is environment friendly. It is completely
renewable and can be produced over and over again on demand.
Hydrogen can also be used to make bombs like the ones used by
America on Hiroshima and Nagasaki which makes it highly
inflammable. Dependency on fossil fuels still remains as we need them
to extract hydrogen from other elements. Also, it is quite expensive to
produce and store.
These are some of the alternative energy sources that can be taken
into consideration when planning your energy production and usage.
You can harness any of these and you will satisfy your power needs.
Non-renewable energy comes from sources that will run out or will not be replenished in our lifetimes—or even in many, many lifetimes.
Most non-renewable energy sources are fossil fuels: coal, petroleum, and natural gas. Carbon is the main element in fossil fuels. For this reason, the time period that fossil fuels formed (about 360-300 million years ago) is called the Carboniferous Period.
All fossil fuels formed in a similar way. Hundreds of millions of years ago, even before the dinosaurs, Earth had a different landscape. It was covered with wide, shallow seas and swampy forests.
Plants, algae, and plankton grew in these ancient wetlands. They absorbed sunlight and created energy through photosynthesis. When they died, the organisms drifted to the
bottom of the sea or lake. There was energy stored in the plants and animals when they died.
Over time, the dead plants were crushed under the seabed. Rocks and other sediment piled on top of them, creating high heat and pressure underground. In this environment, the plant and animal remains eventually turned into fossil fuels (coal, natural gas, and petroleum). Today, there are huge underground pockets (called reservoirs) of these non-renewable sources of energy all over the world.
Advantages and Disadvantages Fossil fuels are a valuable source of energy. They are relatively inexpensive to extract. They can also be stored, piped, or shipped anywhere in the world.
However, burning fossil fuels is harmful for the environment. When coal and oil are burned, they release particles that can pollute the air, water, and land. Some of these particles are caught and set aside, but many of them are released into the air.
Burning fossil fuels also upsets Earth’s “carbon budget,” which balances the carbon in the ocean, earth, and air. When fossil fuels are combusted (heated), they release carbon dioxide into the atmosphere. Carbon dioxide is a gas that keeps heat in Earth’s atmosphere, a process called the “greenhouse effect.” The greenhouse effect is necessary to life on Earth, but relies on a balanced carbon budget.
The carbon in fossil fuels has been sequestered, or stored, underground for millions of years. By removing this sequestered carbon from the earth and releasing it into the atmosphere, Earth’s carbon budget is out of balance. This contributes to temperatures rising faster than organisms can adapt.
Coal
Coal is a black or brownish rock. We burn coal to create energy. Coal is ranked depending on how much “carbonization” it has gone through. Carbonization is the process that ancient organisms undergo to become coal. About 3 meters (10 feet) of solid vegetation crushed together into .3 meter (1 foot) of coal!
Peat is the lowest rank of coal. It has gone through the least amount of carbonization. It is an important fuel in areas of the world including Scotland, Ireland, and Finland.
Anthracite is the highest rank of coal. Anthracite forms in regions of the world where there have been giant movements of the earth, such as the formation of mountain ranges. The Appalachian Mountains, in the eastern part of the United States, are rich in anthracite.
We mine coal out of the ground so we can burn it for energy. There are two ways that we can mine coal: underground mining and surface mining.
Underground mining is used when the coal is located below the surface of the Earth, sometimes 300 meters (1,000 feet) deep—that’s deeper than most of the Great Lakes!
We use oil for many things. About half of the world’s petroleum is converted into gasoline. The rest can be processed and used in liquid products such as nail polish and rubbing alcohol, or solid products such as water pipes, shoes, crayons, roofing, vitamin capsules, and thousands of other items.
Advantages and Disadvantages There are advantages to drilling for oil. It is relatively inexpensive to extract. It is also a reliable and dependable source of energy and money for the local community.
Oil provides us with thousands of conveniences. In the form of gasoline, it is a portable source of energy that gives us the power to drive places. Petroleum is also an ingredient in many items that we depend on.
However, burning gasoline is harmful to the environment. It releases hazardous gases and fumes into the air that we breathe. There is also the possibility of an oil spill. If there is a problem with the drilling machinery, the oil can explode out of the well and spill into the ocean or surrounding land. Oil spills are environmental disasters, especially offshore spills. Oil floats on water, so it can look like food to fish and ruin birds’ feathers.
Natural Gas
Natural gas is another fossil fuel that is trapped underground in reservoirs. It is mostly made up of methane. You may have smelled methane before. The decomposing material in landfills also release methane, which smells like rotten eggs.
There is so much natural gas underground that it is measured in million, billion, or trillion cubic meters.
Natural gas is found in deposits a few hundred meters underground. In order to get natural gas out of the ground, companies drill straight down. However, natural gas does not form in big open pockets. Natural gas is trapped in rock formations that can stretch for kilometers.
To reach natural gas, some companies use a process called “hydraulic fracturing,” or fracking. Hydraulic means they use water, and fracturing means to “split apart.” The process uses high-pressure water to split apart the rocks underground. This releases the natural gas that is trapped in rock formations. If the rock is too hard, they can send acid down the well to dissolve the rock. They can also use tiny grains of glass or sand to prop open the rock and let the gas escape.
We use natural gas for heating and cooking. Natural gas can also be burned to generate electricity. We rely on natural gas to give power to lights, televisions, air conditioners, and kitchen appliances in our homes.
Natural gas can also be turned into a liquid form, called liquid natural gas (LNG). LNG is much cleaner than any other fossil fuels.
Liquid natural gas takes up much less space than the gaseous form. The amount of natural gas that would fit into a big beach ball would fit into a ping-pong ball as a liquid! LNG can be easily stored and used for different purposes. LNG can even be a replacement for gasoline.
Advantages and Disadvantages Natural gas is relatively inexpensive to extract, and is a “cleaner” fossil fuel than oil or coal. When natural gas is burned, it only releases carbon dioxide and water vapor (which are the exact same gases that we breathe out when we exhale!) This is healthier than burning coal.
However, extracting natural gas can cause environmental problems. Fracturing rocks can cause mini-earthquakes. The high-pressure water and chemicals that are forced underground can also leak to other sources of water. The water sources, used for drinking or bathing, can become contaminated and unsafe.
Other Non-renewable Energy Sources
Fossil fuels are the leading non-renewable energy sources around the world. There are others, however.
Nuclear Energy Nuclear energy is usually considered another non-renewable energy source. Although nuclear energy itself is a renewable energy source, the material used in nuclear power plants is not.
Nuclear energy harvests the powerful energy in the nucleus, or core, of an atom. Nuclear energy is released through nuclear fission, the process where the nucleus of an atom splits. Nuclear power plants are complex machines that can control nuclear fission to produce electricity.
The material most often used in nuclear power plants is the element uranium. Although uranium is found in rocks all over the world, nuclear power plants usually use a very rare type of uranium, U-235. Uranium is a non-renewable resource.
Nuclear energy is a popular way of generating electricity around the world. Nuclear power plants do not pollute the air or emit greenhouse gases. They can be built in rural or urban areas, and do not destroy the environment around them.
However, nuclear energy is difficult to harvest. Nuclear power plants are very complicated to build and run. Many communities do not have the scientists and engineers to develop a safe and reliable nuclear energy program.
Nuclear energy also produces radioactive material. Radioactive waste can be extremely toxic, causing burns and increasing the risk for cancers, blood diseases, and bone decay among people who are exposed to it.
Biomass Energy
