An article from: https://impactful.ninja/clean-vs-green-energy-differences/
You have probably heard the terms clean and green when talking about energy sources. They may have even been used interchangeably. But did you know that they have two different meanings? To make informed decisions about how we generate our energy, we must identify the differences, benefits, and drawbacks of both clean and green energy.
Clean energy is the generation of energy that does not produce greenhouse gas emissions. Green energy is the generation of energy from infinite sources that does not produce carbon emissions or negatively impact the environment. Knowing their differences can help combat our current climate crisis.
Both clean and green energy sources are sustainable energy options to replace fossil fuels (e.g. coal and natural gas). So how do we tell the difference between them? Which energy sources are classified as clean? Green? Both? Below we will define both terms and have a look at which of the six major non-fossil energy sources fall into each category.
How Are Clean Energy and Green Energy Defined
The end goal of fossil fuel (e.g., coal and oil) alternatives is to reduce the effects of global warming by limiting global greenhouse gas (GHG) emissions. And clean and green energy are no exception.
What Does the Dictionary Say About Clean Energy and Green Energy
Both clean and green energy have the same end goals of reducing global greenhouse gas emissions and combating global climate change. But there are still some differences between these two.
“Clean Energy: energy, as electricity or nuclear power, that does not pollute the atmosphere when used, as opposed to coal and oil”
Clean energy is derived from processes that do not release GHG emissions into the atmosphere.
“Green Energy: energy that can be produced in a way that protects the natural environment, for example by using wind, water, or the sun”
Green energy is a subset of renewable energy that includes a zero-emissions profile and carbon footprint reductions to provide the highest environmental benefit.
Both clean and green energy sources do not emit GHGs, but only green energy sources have the added benefits of being renewable and not negatively impacting the environment.
What Do These Differences Mean
Clean energy and green energy have different ramifications on our environment because of the nuances in their definitions:
If energy is only clean but NOT green: the generation of energy does not produce GHGs (or other pollution), but either the resource is non-renewable and/or it has negative effects on the environment.
If energy is only green but NOT clean: This category does not exist because all green energy is by definition also clean energy. Green energy is renewable, does not emit GHGs, and does not harm the environment, while clean energy “only” does not emit GHGs (but may have a finite resource supply or harm the environment).
Essentially, clean energy means zero GHG emissions, without determining whether the resource is renewable or can potentially harm the environment. Green energy is renewable and neither pollutes the atmosphere nor harms the environment.
What Are the Differences and Similarities Between Clean Energy and Green Energy
The best way to lower your carbon footprint is to choose energy sources that are both clean AND renewable.
Both Clean and Green Energy include Solar, Wind, Geothermal & Low-Impact Hydropower
Clean but not Green: Nuclear
All Green Energy is Clean Energy
Renewable energy that is neither Clean nor Green:
Large Hydropower Biomass
Classifying an energy source as clean, green, both, or neither requires an in-depth look at the longevity of the resource, the carbon emissions profile, and its impact on the environment.
Which Energies are Both Clean Energy and Green Energy
If energy is both clean AND green, the generation of energy does not produce GHGs or harm the environment, and the resource is renewable.
Solar Energy: photovoltaic cells in solar panels absorb energy from sunlight, creating an electrical charge that moves in response to an internal electric field in the cell and creates electricity. This process is renewable because the sun will continue to emit energy until it goes supernova. It is also clean because no GHGs are emitted during operation. Following proper disposal methods of hazardous chemicals associated with PVCs and placing solar panels in less populated areas or on top of buildings minimizes any negative environmental impacts, making it a green energy source.
Wind Energy: wind turns the blades of wind turbines around a rotor, which spins a generator to generate electricity. This process is renewable because as long as the wind blows, wind power can be harnessed. It is also clean because no GHGs are emitted during its operation. Land use, wildlife impact, and public health concerns are mitigated by proper planning and siting of wind farms, making it a green energy source.
Geothermal Energy: drilling down to hot water reservoirs creates steam that rotates a turbine, which spins a generator to generate electricity. This process is renewable because the Earth has an almost unlimited supply of heat generated by its core, and the water extracted from the reservoirs can be recycled via re-injection into the ground. It is also clean because although it does release minute amounts of carbon dioxide, the amount is very small. Negative environmental impacts are minimized by only drilling to shallow depths, siting power plants away from major fault lines, and properly disposing of hazardous waste captured by the scrubbers, making it a green energy source.
Low-Impact Hydropower: projects that generate 10 MW or less of power. Flowing water turns turbines, which spins a generator to generate electricity. This process is renewable because the water cycle is a continuous process that recharges itself. It is also clean because, on a small scale, hydropower produces very few GHGs. Installing small turbines in irrigation canals, water-treatment plant outfalls, and existing hydroelectric facilities mitigates emissions and environmental impact, making it a green energy source.
Solar, wind, geothermal, and low-impact hydropower are all examples of BOTH green and clean energy because their generation does not produce GHG emissions or harm the environment, and their resource supply renewable.
Which Energies Are Only Clean Energy But Not Green Energy
If energy is only clean but NOT green, the generation of energy does not produce GHGs, but it is either nonrenewable or negatively impacts the environment.
Nuclear Energy: in nuclear fission, an enormous amount of energy is released when electromagnetic radiation is used to split the nucleus of a uranium atom (U-235). The process of nuclear fission is clean because it does not produce GHG emissions, but nuclear energy is not green because it does require mining, extraction, and long-term radioactive waste storage which are threats to the environment. It is also not renewable because there is a finite supply of U-235, the uranium isotope used in nuclear power plants, on Earth. We have already used up most of our U-235 because it has a half-life of about 700 million years.
Nuclear energy is clean because the generation of energy does not produce GHGs. It is not green though because mining, extraction, and long-term radioactive waste storage are threats to the environment, and U-235 is a nonrenewable resource.
Which Renewable Energies Are Neither Clean Nor Green
If energy is NEITHER clean NOR green, the energy source is either nonrenewable, produces GHG emissions, harms the environment, or all of the above. They are still important in the fight against climate change though, as we will see later on! Below are the energy sources that are neither clean nor green.
Biomass: Wood, agricultural crops, biogenic materials, animal manure, and human sewage contain stored chemical energy from the sun which is burned for heat or converted to fuel. It is not clean because the combustion of biomass materials releases sequestered carbon dioxide, nitrogen oxides, and sulfur oxides in the biomass material into the atmosphere. Albeit, the amount released is much less than is released from fossil fuels. It is also not green because the biomass industry is responsible for clearcutting forests and reducing both plant and animal biodiversity.
Large Hydropower: facilities that have a capacity of more than 30 megawatts (MW). Flowing water turns turbines, which spins a generator to generate electricity. This process is not clean because the construction of large hydroelectric facilities and biomass decomposition in the reservoirs produces GHG emissions (e.g. carbon dioxide and methane), although the rate of emissions is much lower than that of fossil fuels. It is also not green because large dams that create reservoirs can obstruct fish migration, alter the water temperature and chemistry, and flood out adjacent lands.
Just because an energy source is neither clean nor green, doesn’t mean we should discount it as a replacement for fossil fuels. Biomass and large hydropower are both renewable energies. Implementing technology to reduce the level of GHG emissions and protect the environment can increase their viability as fossil-fuel substitutes.
Why Is it Important to Differentiate Difference Between Clean and Green Energy
Understanding and differentiating between the benefits and drawbacks of clean and green energy is important when discussing their implications on our environment.
Benefits: No GHG emissions, non-polluting.
Drawbacks: Some have Intermittent production, geographic limitations, or nuclear waste byproducts
Benefits: Reduces carbon footprint, air pollution, and water environmental impacts; infinite energy supply; promotes decentralization; potentially no GHG emissions and non-polluting.
Drawbacks: High up-front cost; some have intermittent production, geographic limitations, lower quantities of energy produced
Clean energy does not produce GHG emissions, or any other environmental pollution, which aids in the fight against global climate change. However, clean energy possesses geographic limitations and offers intermittent production peaks depending on weather conditions (that could highly benefit from a smart grid). Also, when it comes to nuclear energy, safe storage and containment of nuclear waste byproducts (radioactive waste) is a big and still unsolved concern.
Green Energy is a more specific category of renewable energy that provides higher environmental benefits than renewables. It can also reduce carbon footprints, air pollution, and water environmental costs. However, green energy possesses geographic limitations and offers intermittent production peaks depending on weather conditions (that could highly benefit from a smart grid).
Both clean and green energy are an integral part of helping us overcome our current climate crisis. This is why it is important to know the difference between the two!