Clean energy is a hot topic. Coal, gas, and oil are polluting fuels that have been used extensively to produce energy throughout the 20th century. As the levels of carbon dioxide (CO2) increase in the atmosphere, scientists and politicians are looking for new, non-polluting sources of energy. Terms like green energy, alternative energy sources, and clean energy are popping up around us to describe ways to produce energy without harming the environment.
What exactly does each term mean, though? Is renewable energy the same as clean energy? What are the types of clean energy, alternative energy, and green energy?
This handy glossary will help you understand the terminology of clean energy in plain English.
Alternative energy sources are all the sources that are not derived from fossil fuels such as gas, oil, or coal.
Sometimes alternative energy is used interchangeably with renewable energy. However, there are some small differences. For instance, nuclear energy is not based on fossil fuel; therefore, it is an alternative energy source. But it is not renewable energy because the uranium needed for nuclear energy is not renewable.
People use the term alternative energy to signify any source of energy that does not produce carbon dioxide.
Biomass refers to the organic material produced from plants and animals. Think of fallen leaves and branches, animal manure, waste wood, and leftover crops.
Biomass is renewable because Earth is providing us with an endless supply of it. However, when we burn it to produce energy, we produce carbon emissions. Therefore, biomass is considered a renewable source of energy but not a clean one.
Clean energy is used to signify all energy sources that are not polluting.
Renewable energy is clean energy because it produces no greenhouse gases. You may see the terms clean energy and renewable energy used interchangeably. Even though these terms are quite close, they are not exactly the same. For example, geothermal energy is renewable but not absolutely clean because its process can be lightly polluting.
Fossil fuels were made millions of years ago from the decomposition of dead organisms and plants. Fossil fuels include gas, oil, and coal. Up until now, burning fossil fuels was the main way of producing energy.
However, when burning fossil fuels, we produce carbon dioxide (CO2), which is the main gas that contributes to global warming and climate change. Given many people’s increased sensitivity to environmental issues, the demand to limit the use of fossil fuels is growing.
Deep inside the earth, temperatures are as high as on the sun. If you have ever been to a hot spring, you probably enjoyed the hot water bubbling to the surface.
This concept is the basis of geothermal power. Heat is pumped from deep inside the earth. It warms up water to produce steam. The steam then spins a turbine linked to a generator, thus producing electricity.
While solar panels can be installed in most areas around the country, geothermal power can only be harnessed in specific areas. In the United States, these areas typically lie in western parts of the country.
Renewable sources of energy are the sources that cannot be depleted, no matter how much we use them.
Renewable energy refers to all energy that is produced from renewable sources. Think of sunshine. Regardless of how much sunshine we use to power our solar panels today, there will be plenty of sunshine tomorrow as well as next week, next month, and next year. The amount we use today does not diminish the energy source.
The same is true for wind power, tidal power, or geothermal power. All these energy sources are renewable.
Solar energy is probably the most common renewable energy source. Solar cells gather sunlight and transform it into electricity. Solar panels can be installed on house rooftops.
On a larger scale, solar farms have hundreds or thousands of solar panels installed. These gather sunlight and generate enough power that can provide electricity to entire neighborhoods, communities, or even small towns.
Sustainable energy includes the forms of energy we use to cover our current energy needs without endangering their availability for future generations.
Using sun or wind to cover our current energy needs does not diminish their availability for future generations. Renewable energy is sustainable energy because it does not get depleted; therefore, its use today does not endanger its availability tomorrow.
Fossil fuels are not sustainable because they are finite. Once we started to use them, their availability began to decrease. Earth will run out of them eventually, no matter how many new oil or gas fields are discovered.
Tidal and wave power
Tidal power takes advantage of the changes in tides, while wave power uses the movement of waves to generate power.
Both of these are still largely experimental and have not been commercially developed as widely as solar or wind power.
Obviously, tidal power can only work in places where tides exist, and wave power requires fast-moving waves.
Water and hydropower
Just like windmills used to harness the power of the wind, so do water mills.
People constructed water mills on waterfalls or rushing rivers to exploit the power of fast-running water that moved a waterwheel.
Hydropower creates energy by the movement created by fast-moving water either on a river or from a high-point (waterfall). The fast-moving water spins a generator’s blades and produces electricity.
Humanity harnessed wind power hundreds of years ago when we built up the first windmills which ground flour or moved machinery. Starting with this basic technology, scientists and businesses have developed huge wind turbines to create electricity. These are usually positioned on top of mountains or hills to take the most advantage of high wind speeds. Once the turbines start turning, they produce clean energy.
What are the benefits of clean energy?
Changing the way we produce energy is feasible. Making small changes in everyday lives might look insignificant on a personal level but can be huge at a collective level.
Switching to green energy only affects our pocket marginally (if at all). Making sure we are responsible energy consumers means that we can lead comfortable lives while making small environmental concessions.
Small steps like that can make our future brighter and happier!