Green and renewable energy sources are sustainable energy options to replace fossil fuels (e.g. coal and natural gas). Sometimes the two are used synonymously, but did you know there are instances where they are not mutually exclusive? To make informed decisions about how we generate our energy, we must identify the differences between the two. So we had to ask: What’s the difference between green and renewable energy?

Green energy is the generation of energy from infinite sources that does not produce carbon emissions or negatively impact the environment. Renewable energy is the generation of energy from infinite sources. Knowing their differences aids in the fight against global climate change.

In aiming for a more sustainable future, how can we tell the difference between green and renewable energy? Which energy sources are classified as green? Renewable? Both? All of those answers can be found below, where 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 Green Energy and Renewable Energy Defined

The goal of most alternatives to fossil fuels is to reduce the effects of global warming by limiting global greenhouse gas emissions. And green and renewable energy are no exception. 

What Does the Dictionary Say About Green Energy and Renewable Energy

Green and renewable energy sources share the same end goals of reducing global greenhouse gas emissions and combating global climate change. However, they have slight differences that are worth noting when discussing their impact on our environment.

“Green Energy: energy that can be produced in a way that protects the natural environment, for example by using wind, water, or the sun”

Cambridge Dictionary

Green energy is a subset of renewable energy that includes a zero-emissions profile and carbon footprint reductions to provide the highest environmental benefit. 

“Renewable Energy: energy that is produced using the sun, wind, etc., or from crops, rather than using fuels such as oil or coal | types of energy that can be replaced naturally such as energy produced from wind or water”

Cambridge Dictionary

Renewable energy is sustainable because the energy sources are in infinite supply, and we can keep harvesting them for years to come. 

Both green and renewable energy sources are in infinite supply, but only green energy sources have the added benefit of not producing greenhouse gas emissions or negatively impacting the environment. 

What Do These Differences Mean

The difference between green energy and renewable energy comes down to the carbon emissions profile and carbon footprint reduction.

• If energy is only green but NOT renewable: This category does not exist because all green energy is by definition also renewable energy. Green energy is in infinite supply AND does not produce greenhouse gas emissions or harm the environment, while renewable energy “only” is in infinite supply (but may or may not generate greenhouse gas emissions or harm the environment). 

• If energy is only renewable but NOT green: the energy source is in infinite supply, but energy generation produces greenhouse gas emissions. For example, large hydropower is renewable because the water cycle is a perpetual process. It is not green though because it produces greenhouse gas emissions and can negatively impact the environment.

Basically, all green energy is renewable energy, but not all renewable energy is green energy. Green energy is a subset of renewable energy that comes from those sources that provide the highest environmental benefit. 

What Are the Differences and Similarities Between Green Energy and Renewable Energy

Choosing either a green or renewable energy source is great if you are looking to lower your carbon footprint. But you know what’s better? Choosing energy sources that are both green AND renewable!

Analyzing the carbon emissions profile of an energy source and determining if there is an infinite supply is necessary to categorize energy as green, renewable, both, or neither.

Which Energies are Both Green Energy and Renewable Energy

If energy is both green AND renewable, the generation of energy does not produce greenhouse gas emissions, and the energy source is in infinite supply. Below are the energy sources that are both green and renewable.

• Geothermal Energy: drilling down to hot water reservoirs creates steam that rotates a turbine, which spins a generator to generate electricity. This process is deemed green because although it does release minute amounts of carbon dioxide, the amount is, well, minute. Geothermal is also 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. 

• 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 green because, on a small scale, hydropower produces very few greenhouse gases and has little to no environmental impact. Installing small turbines in irrigation canals, water-treatment plant outfalls, and existing hydroelectric facilities mitigates emissions and environmental impact.

• 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 green because no greenhouse gases are emitted during operation, and 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. It is also renewable because the sun will continue to emit energy until it goes supernova. 

• Wind Power: wind turns the blades of wind turbines around a rotor, which spins a generator to generate electricity. This process is green because no greenhouse gases are emitted during its operation. It is also renewable because as long as the wind blows, wind power can be harnessed. 

Geothermal, solar, low-impact hydropower, and wind are all examples of both green and renewable energy because their generation does not produce greenhouse gas emissions and their resource supply is infinite. 

Which Energies Are Only Renewable Energy But Not Green Energy

If energy is only renewable but NOT green, the energy source is in infinite supply, but the generation of energy does produce greenhouse gas emissions. Below are the energy sources that are renewable but not 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. This process is renewable because it can be replenished by planting trees and agricultural crops. It is not green though 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.

• 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 renewable because the water cycle is a continuous process that recharges itself. It is not green though because the construction of large hydroelectric facilities and biomass decomposition in the reservoirs produces greenhouse gas emissions (e.g. carbon dioxide and methane), although the rate of emissions is much lower than that of fossil fuels. Also, dams that create reservoirs can obstruct fish migration, alter the water temperature and chemistry, and flood out adjacent lands.

Both biomass and large hydropower are renewable energy sources because they can be naturally replenished over time. They are not green though because they produce greenhouse gas emissions upon generation.

Which Non-Fossil Energies Are Neither Green Nor Renewable

If energy is NEITHER green NOR renewable, the energy source is either finite, produces greenhouse gas emissions, harms the environment, or all of the above. They are still important in the fight against climate change though, as we will discuss later on! Below are the energy sources that are neither green nor renewable

• 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 does not produce greenhouse gas 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.

So if an energy source is neither green nor alternative, does this mean we shouldn’t use it as a replacement for fossil fuels? Absolutely not! Nuclear power is still a viable substitute for fossil fuels because it is a clean energy source, meaning it does not produce greenhouse gas emissions. Ways to minimize negative environmental impacts include the proper handling, transportation, storage, and disposal of radioactive waste. 

Why Is it Important to Differentiate Difference Between Green and Renewable Energy

Green and renewable energy have benefits and drawbacks that are important to understand and differentiate between. The slight differences in their definitions have different implications for our environment. 

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). 

Renewable energy is by definition infinite because the resources naturally replace themselves over time. It is also mostly non-polluting, low-maintenance, and promotes the decentralization of energy supply. On the flip side, renewable energy comes with some of the same drawbacks that green energy comes with, including lower immediate quantities of energy compared to non-renewable energy sources (e.g., coal and oil). 

So, both green and renewable energy have drawbacks. But this doesn’t mean we shouldn’t use them as substitutes for fossil fuels! The benefits they provide still make them an integral part of fighting our current climate crisis.

How Do Green and Renewable Energy Benefit the Environment

Green and renewable energy sources could be key to overcoming the current climate crisis. Here are how they can make a big impact:

1. Climate Change Mitigation: green energy does not emit carbon dioxide, nitrogen oxides, sulfur dioxides, or mercury into the atmosphere, soil, or water. These pollutants are known to contribute to the thinning of the ozone layer, global sea-level rise, and the melting of our world’s glaciers. It also aims to provide the lowest level of environmental harm.

2. Energy Independence: Being able to produce our own electricity in the U.S. without the aid of foreign countries is an important step to help us become more self-sufficient instead. Former President George W. Bush signed the Energy Independence and Security Act of 2007 to reduce U.S. dependence on oil, expand the production of renewable fuels (and confront global climate change). 

3. Employment Opportunities: The renewable energy sector employed 11.5 million people worldwide in 2019, with solar energy making up the bulk of those jobs. Renewable energy jobs continue to increase as we start to realize just how beneficial renewable energy is for our environment. 

Renewable energy accounted for 11% of total energy consumption in the United States in 2019. This was equal to the amount of coal consumption and was nearly three times greater than consumption in 2000. Experts predict renewable resource consumption will continue to increase through 2050 as more and more effort is put into reducing global greenhouse gas emissions. 

However, we still have a long way to go to make green or renewable energy sources our primary form of energy. Only a very few countries have renewables as their primary energy source, while the vast majority of countries still have a long way to go.

Final Thoughts

Green energy and renewable energy are sustainability terms that have different meanings. Knowing that difference and using the correct term is important when talking about a future that uses green and/ or renewable energy. Both are in infinite supply, but green energy is a more specific and stricter definition of renewable energy that includes energy sources that provide the highest level of environmental benefits. All green energy sources are renewable, but not vice versa.

Of the energy sources described above, nuclear power is neither green nor renewable. But this doesn’t necessarily make it a bad choice as a substitute for fossil fuels! Before we can make decisions regarding ways to generate energy more sustainably in the future, we must assess the level of greenhouse gas emissions and construct ways to minimize negative environmental impacts.

Stay impactful,

Sources

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• National Renewable Energy Laboratory: Geothermal Electricity Production Basics
• Office of Energy Efficiency and Renewable Energy: How Hydropower Works
• Office of Energy Efficiency and Renewable Energy: Types of Hydropower Plants
• National Hydropower Association: Small Hydro
• High Country Conservation Center: What’s the Difference Between Clean & Renewable Energy?
• Office of Energy Efficiency and Renewable Energy: How Does Solar Work?
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