Clean energy is the generation of energy from sources that produce virtually no greenhouse gas emissions. Given the worsening climate crisis, clean energy has to come to represent a larger share of the overall energy market. So we had to ask: What is the history of clean energy?

Clean energy began thousands of years ago via harnessing energy from the sun, wind, heat from the earth’s core, tides, waves, and radioactivity. Theoretical and experimental validation of clean energy mechanisms, followed by the invention of clean energy technologies, have shaped the modern market.

Keep reading to learn how clean energy came to be, who and what pioneered its development, how effective it has been thus far, and what the future of clean energy could entail. 

Here’s the History of Clean Energy in a Nutshell

Clean energy is an energy substitute for fossil fuels (e.g., coal, oil, natural gas) that can reduce the effects of global warming by limiting global greenhouse gas emissions (GHGs). It is derived from processes that release minute amounts of GHGs into our atmosphere. 

“Clean Energy: energy, as electricity or nuclear power, that does not pollute the atmosphere when used, as opposed to coal and oil”

Collins Dictionary

The 6 types of clean energy are solar, wind, geothermal, tidal, wave, and nuclear energy.

Clean energy has gone through three distinct development phases in its development:

• Early market formation and innovation: The early history of clean energy dates back thousands of years with primitive methods of harnessing the sun, wind, heat from the earth’s core, tides, waves, and radioactivity. Scientific advances in the 1800-1900s paved the way for the development of modern clean energy technologies.

• Consolidation and strengthening: Theoretical and experimental validation of clean energy mechanisms, followed by the invention of solar panels, wind turbines, geothermal plants, tidal facilities, wave converters, and nuclear reactors, helped to shape the clean energy market.

• Mainstreaming: Clean energy began to establish itself as a part of the mainstream electricity industry in the 1900s with the opening of the first commercial power plants and rapid scaling of the technology. The establishment of the International Energy Agency (IEA), the International Renewable Energy Agency (IRENA), and the Paris Climate Agreement helped to regulate the clean energy market.

Understanding clean energy’s history can provide insight into how it has evolved into the energy source it is today.

When and How Did Clean Energy Get Started

In general, we have been using clean energy for centuries. But each type of clean energy got its start differently.

• Solar: Humans have been using the sun as energy since the 7th century BC. Common ancient uses of the sun included actively reflecting the sun’s rays and passively allowing the sun to act as a source of heat. In 1839, French physicist Alexandre Edmond Becquerel discovered the photovoltaic effect, which would lead to the development of the photoelectric (PV solar) cell, the basis of modern solar energy. 

• Wind: Humans have been using wind as energy since 5,000 BC, when wind was used to power sailboats down the Nile River in Egypt. In 1,000 AD, wind technology made its way to Europe, where windmills were used to produce food, pump water, grind wheat and grains, and cut wood.

• Geothermal: Humans have been using geothermal energy, in the form of natural pools and hot springs, for centuries. The Greeks and the Romans used baths heated by hot springs, and instances of geothermal space heating in the city of Pompeii have been documented as far back as the first century AD. Evidence was also discovered that Native Americans used geothermal energy in cooking applications as early as 10,000 years ago. 

• Tidal: The early history of tidal energy dates back to the 600s with the use of tide mills, which are water mills driven by the rise and fall of tides. Tide mills grew in popularity throughout the Middle Ages, and hundreds were in operation around the shores of the Atlantic Ocean by the 1800s. 

• Wave: The early history of wave energy dates back to the last months of the 18^th century when French inventor Girard and his son patented the first wave energy technology. Between 1856 and 1973 there were hundreds of patents filed worldwide, with over 300 in the United Kingdom (UK) alone. 

• Nuclear: The early history of nuclear power involved studies about the science of atomic radiation, the atomic model, and the fission and fusion processes. In 1934, Italian physicist Enrico Fermi unknowingly directed the first controlled chain reaction involving nuclear fission. And also in 1934, Australian physicist Mark Oliphant became the first to demonstrate nuclear fusion in a laboratory setting. 

How Has Clean Energy Developed Over Time

Over the years, clean energies have grown to make up an ever-growing amount of total energy consumption and play a vital role in combating climate change. As concern increases over the worsening climate crisis, attention shifts towards developing clean energy.

What Are Milestones in Clean Energy Development 

The 1800s and 1900s saw rapid refinement and development of clean energy technologies

1818: François Jacques de Larderel became the first to harness geothermal energy for industrial use by extracting boric acid from hot springs.

1883: The first photoelectric (solar) cell was invented. 

1887: The first wind turbine for electricity generation was developed.

1904: Piero Ginori Conti became the first to use geothermal energy to power a small generator to illuminate several light bulbs. 

1907: The Hot Lake Hotel became one of the first buildings in the world to use geothermal energy as its primary heat source.

1910: Busso Belasek developed the first artificial wave machine.

1910: Bochaux Praceique developed the first oscillating water column for wave energy, which is a design still used today. 

1913: The world’s first commercial, dry steam power plant was constructed in Italy. 

1920s: The first vertical axis wind turbine was developed.

1920: Dexter Cooper came up with the idea of harnessing power from tides.

1934: Enrico Fermi unknowingly directed the first controlled chain reaction involving nuclear fission. Mark Oliphant demonstrated nuclear fusion in a laboratory setting and discovered helium-3 and tritium.

1938: Otto Hahn and Fritz Straßmann experimentally proved the process of nuclear fission. 

1939: Otto Frisch and William Arnold coined the term “fission”. Hans Bethe and Subrahmanyan Chandrasekhar figured out the precise subatomic process of fusion.

1940: Yoshio Masuda developed a navigation buoy powered by wave energy. He is often regarded as the father of modern wave energy technology.

1941: The first megawatt (MW) wind turbine was constructed and connected to the US power grid. 

1948: The world’s first commercial geothermal heat pump became operational. This pioneered the large-scale commercial application of heat pumps. 

1950s: Andrei Sakharov and Igor Tamm conceptualized the tokamak, which would become the preferred nuclear fusion reactor today.

1951: Lyman Spitzer invented the stellarator, a type of fusion reactor.

1954: The first silicon solar cell was invented.

1956: Calder Hall, the world’s first commercial nuclear fission power station, became operational.

1958: The world’s first tokamak fusion reactor, the T-1, was constructed in Russia.

1960: The Geysers Geothermal Complex, the world’s largest geothermal power plant, was constructed North of San Francisco, California (US).

1963: The Wairākei Power Station was opened in New Zealand. It was the first flash steam-powered plant and the second overall geothermal power plant in the world.

1963: Sharp Corporation became the first mass-producer of silicon solar panels.

1966: The La Rance Tidal Power Station was opened in France, the first tidal power plant in the world. 

1967: The world’s first geothermal, binary cycle power plant became operational in Russia. This binary cycle design uses lower-temperature geothermal resources, meaning it is more efficient and can be deployed at more locations worldwide.

1980: The world’s first onshore wind farm was constructed in New Hampshire (US).

1983: The Joint European Torus (JET) tokamak was constructed, the largest operational nuclear fusion reactor to achieve nuclear fusion at the time.

1991: The world’s first offshore wind farm, the Vindeby Wind Farm, was constructed in Denmark. 

1991: JET achieved the world’s first controlled release of fusion power.

2003: The European Marine Energy Centre (EMEC) was established as the world’s first commercial, open-sea testing facility for wave and tidal energy technologies.

2006: The Chena Hot Springs Resort installed the world’s first plant to produce geothermal energy at temperatures below the boiling point of water. This expanded the geographic area where geothermal energy can be extracted.

2006: The International Thermonuclear Experimental Reactor (ITER) agreement was signed.

2007: The world’s first tidal turbine system was constructed at Strangford Lough in Northern Ireland.

2007: Solar energy became the leading clean energy technology. 

2008: The world’s first operational wave power system, the Aguçadora wave farm, was opened in Portugal.

2011: The Sihwa Lake Tidal Power Station, the largest operational tidal power plant in the world, was opened in South Korea. 

2018: Construction began on The MeyGen Tidal Energy Project, which will be the largest tidal power facility in the world.

2018: France opened Europe’s first solar panel recycling plant.

2022: The National Ignition Facility at Lawrence Livermore National Laboratory in California (US) demonstrated the viability of nuclear fusion energy for the first time. 

2023: CorPower Ocean installed CorPower C4, the first commercial-scale wave energy converter.

How Has the Clean Energy Market Developed Recently

Solar, wind, geothermal, tidal, and wave energy are by definition both clean and renewable energy. 

• Renewable energy is infinite by definition because the resources naturally replace themselves over time.
• Driven by decreasing costs and improved technology, renewable energy capacity grew over 4 fold from 2000-2022, increasing from 754 gigawatts (GW) to 3,372 GW. Solar energy saw the highest increase at 22% (192 GW), followed by wind at 9% (75 GW), and geothermal at 181 megawatts (MW). 

Nuclear energy, the remaining type of clean energy, is not classified as renewable energy because nuclear fission uses Uranium-235 (U-235), and nuclear fusion uses deuterium and tritium, all of which are in finite supply.

• Both the nuclear fission and nuclear fusion industries saw rapid growth beginning in 1950. In more recent years, nuclear power has seen a relatively stable market.
• Since 2019, installed nuclear fission capacity has decreased slightly from 393 GW to 377 GW, and the number of reactors has decreased from 450 to 411.

What Is the Present Status of Clean Energy

The best data currently available to track clean energy is the data we have on renewable energy because all clean energy is also classified as renewable energy. Renewable energy is also tracked much more closely than clean energy. Although hydropower dominates renewable energy data, it is not a clean energy and is therefore not included in our history of clean energy—yet you’ll find it quite prominently in the graphs below. 

In 2022, we generated roughly 6,700 TWh of clean energy, 4,200 TWh of energy from wind solar, geothermal, wave, and tidal sources combined, and 2,500 TWh from nuclear energy.

Wind is our leading source of clean energy today, generating over 2,000 TWh of energy.

Regarding electricity generation, wind accounts for the majority at roughly 25%, solar at 15%, and other renewables (e.g., geothermal, biomass, waste, wave, and tidal energy) at 9%.

Nuclear fission accounted for roughly 10% of global electricity generation in 2022, generating approximately 2,500 TWh of electricity from approximately 413 GW of installed capacity. 

In terms of nuclear fusion, there are currently more than 10 stellarators and 50 tokamaks in operation worldwide, but there are currently no operating fusion reactors that provide energy to our power grid. The focus remains on refining the technology.

How Will the Future of Clean Energy Look Like

In general, the future of clean energy will be heavily influenced by ambitious government targets, policy support, increasing competitiveness of clean energy technologies, and incentives to use less fossil fuels.

How Clean Energy Will Likely Develop in the Future

More specifically, each type of clean energy has a different future outlook:

• Solar: Photovoltaic solar installed capacity is to exceed natural gas by 2026 and coal by 2027, becoming the largest in the world.

• Wind: Wind and solar energy projects together are on track to contribute more than one-third of the world’s electricity by 2030. Wind energy alone is poised to become the world’s foremost energy generation source.

• Geothermal: One of the most prominent, emerging geothermal technologies is enhanced geothermal systems (EGS), also known as human-made geothermal energy. The future of geothermal energy also involves a switch from dry steam to binary cycle geothermal plants, which are more efficient.

• Tidal: The global marine energy market is predicted to increase by over 20% to be worth $1.54 billion by 2030. But this will heavily depend on whether we can overcome marine energy’s main obstacles: cost, geography, and sea level rise, which is exacerbated by climate change.

• Wave: If fully realized, wave energy could provide us with 500 GW of power and foster a $53 billion per year market. But this will heavily depend on whether we can overcome marine energy’s main obstacles: cost, technology, and geography. 

• Nuclear: Nuclear fission is predicted to continue to play a key role in the clean energy movement for years to come, with experts calling for a capacity increase to 545 GW by 2030 and a tripling of investments to $125 billion per year. In terms of nuclear fusion, most experts agree that we are unlikely to achieve large-scale energy generation before 2050. Research into fusion as a commercially viable energy source still continues.

What Policies Are Put in Place to Support Clean Energy Usage

The most well-known piece of legally binding, international climate mitigation legislation is The Paris Agreement, the goal of which is to limit global warming to below 2 degrees Celsius (C), preferably to 1.5C, compared to pre-industrial levels. 

The Paris Agreement specifically notes the transition away from fossil fuels and towards clean energies as being a critical part of meeting these goals.

Check out the highlights of the 2015 COP21 directly from the UN Climate Change channel:

In addition, The International Energy Agency’s (IEA) Net Zero Emissions by 2050 Scenario is one framework for the global energy sector to achieve net zero CO₂ emissions by 2050 and universal energy access by 2030.

There are many global and country-specific policies and organizations aimed at increasing clean energy usage and meeting the 2050 net zero scenario, including: 

• 1957 – International Atomic Energy Agency (IAEA): The IAEA was founded as fears about nuclear technology began to develop. It is an organization within the United Nations that seeks to promote the safe, secure, and peaceful use of nuclear technologies through international cooperation.

• 1974 – The International Energy Agency (IEA): The IEA was founded in response to the major oil disruptions in 1974. It promotes international energy cooperation and is made up of 31 member countries. 

• 1988 – The International Geothermal Association (IGA): The IGA is a leading, global organization that promotes geothermal energy as a vital part of the transition away from fossil fuels. Today, the IGA has over 5,000 members and 30 affiliate organizations.

• 2001 – World Nuclear Association (WNA): The WNA was established as the leading international organization to represent the global nuclear industry. 

• 2005 – Global Wind Energy Council (GWEC): The GWEC was founded as an international trade association for the wind energy industry. Their members represent 99% of the global installed wind power capacity.

• 2009 – The International Renewable Energy Agency (IRENA): IRENA was founded as a global intergovernmental agency focused on scaling renewable energy. It is comprised of 167 member countries as well as the European Union.

• 2013 – Ocean Energy Europe (OEE): They are the largest global network of marine energy professionals, with over 120 member organizations. They aim to advance tidal and wave energy technologies. 

• 2015 – International Solar Alliance (ISA): The ISA is a treaty-based organization established to create cooperation among solar energy-resource-rich countries and the rest of the world. There are currently 94 member countries.

• 2015 – The Global Geothermal Alliance (GGA): The GGA was established by IRENA as a platform to enhance discussion, cooperation, and coordination between the geothermal industry, policymakers, and stakeholders. Today, the GGA has 52 member countries

• 2018 – The Fusion Industry Association (FIA): The FIA was formed to be the voice of the private, nuclear fusion industry. They are a nonprofit organization comprised of private companies striving to make nuclear fusion commercially viable.

If you are interested in learning more about country-specific energy policies, you can visit the IEA’s policies database and filter by specific energy type.

What Are Currently the Different Types of Clean Energy

The 6 types of clean energy are solar, wind, geothermal, tidal, wave, and nuclear energy.

What Are Currently the Different Types of Solar Energy

Solar energy is the conversion of sunlight into electrical energy.

“Solar Energy: energy that uses the power of the sun to produce electricity”

Cambridge Dictionary

Harnessing the power of the sun falls into two main categories:

1. Photovoltaic (PV) solar cells: photovoltaic cells in solar panels absorb energy from sunlight, creating an electrical charge. This charge moves in response to an internal electric field in the cell, causing electricity to flow. 

2. Concentrating solar thermal plants (CSP): mirrors reflect and concentrate sunlight onto receivers that collect and convert solar energy into heat. This is utilized in very large power plants.

Both systems take the energy from the sun and convert it to electricity, just by slightly different mechanisms.

What Are Currently the Different Types of Wind Energy

Wind energy is the conversion of moving air into electrical energy. It is a form of solar energy that is caused by the uneven heating of the earth’s surface, irregularities of the earth’s surface, and the earth’s rotation. 

“Wind: a current of air moving approximately horizontally, especially one strong enough to be felt”

Cambridge Dictionary

There are two main types of wind energy:

1. Onshore wind energy: Wind turbines are located on land. Construction, transportation, maintenance cost, and infrastructure needed to transmit electricity from onshore turbines to consumers is low. 

2. Offshore wind energy: Wind turbines are located in the ocean or freshwater. Construction, transportation, maintenance cost, and infrastructure needed to transmit electricity from offshore turbines to consumers is high. Offshore turbines are considerably larger than onshore turbines and can cost up to 20% more, and noise pollution, land use, and wildlife impact concerns are minimal compared to onshore turbines. 

To harness wind energy, the wind turns wind turbine blades around a rotor, which spins a generator to create electricity. 

What Are Currently the Different Types of Geothermal Energy

Geothermal energy is the conversion of heat inside of the earth into electric energy. It is created by the decay of radioactive materials in the rock and fluid of the earth’s core. 

“Geothermal: involving or produced by the heat that is inside the earth”

Cambridge Dictionary

The three main types of geothermal power plants are: 

1. Dry Steam: Wells are drilled into underground reservoirs of steam. The steam is piped directly from the well to the power plant where it powers turbines and generators.

2. Flash Steam: The most common type of geothermal power plant. Very hot (360 degrees Fahrenheit, 182 degrees Celsius) water flows up through wells towards the surface under its own pressure. As it reaches the surface, some of the water boils into steam. The steam is then separated from the water and is then used to power turbines and generators at the power plant.

3. Binary Steam: Wells are drilled into underground reservoirs of hot water (225-360 degrees Fahrenheit, 107-182 degrees Celsius). The heat from the water is used to boil a working fluid, an organic compound with a low boiling point. This working fluid is vaporized into steam which is then used to power turbines and generators at the power plant. The water is then injected back into the ground where it is reheated and can be used again.

What Are Currently the Different Types of Tidal Energy

Tidal energy is the conversion of the earth’s tides into electrical energy. It is created by the gravitational pull of the sun and moon coupled with the rotation of the earth.

“Tidal Power: power that comes from the movement of the tide (= the rise and fall of the ocean that happens twice every day) and that can be used especially for producing electricity”

Cambridge Dictionary

There are three types of tidal energy technology:

• Stream: turbines are placed in tidal streams. The machines are large and can disrupt the tides. The size of the turbine and the location of the tidal stream will dictate the level of environmental impact.

• Barrage: a barrage (dam) is placed across a river, bay, or estuary. The barrage gates open as the tide rises and close at high tide, creating a lagoon. The water is then released through the turbines which spin a generator to create electricity. Barrages cause significant land disruption within the tidal range, and the change in water and salinity levels within the lagoon can harm plant and animal life. Also, turbines in barrages move fast and can kill marine life in their blades. 

• Lagoon: a body of ocean water that is partially enclosed by a man-made barrier. Lagoons function in the same manner as a barrage, but they generate continuous power and can also be constructed along a coastline. Lagoons provide a minimal level of environmental impact but also generate the least amount of energy. They can be constructed with natural materials like rock and would easily allow marine life to pass through. 

What Are Currently the Different Types of Wave Energy

Wave energy is the conversion of the up and down motion of waves into electrical energy. It is created when the wind blows over the surface of the water on oceans or lakes. 

“Wave Power: electrical energy generated by harnessing the up-and-down motion of ocean waves”

Britannica

There are three types of wave energy technology:

• Float or buoy: Anchored buoys use the rise and fall of waves to power hydraulic pumps. The “up” and “down” movement powers a generator to produce electricity, which is transported onshore via underwater power cables. 

• Oscillating water column: The “in” and “out” motion of waves at the shore enter columns, forcing air to turn turbines. As the waves enter the column, the air is compressed and heated, creating energy. The energy is then transported onshore via underwater power cables. 

• Tapered channel (tapchan): Shore-mounted structures channel and concentrate waves, pushing them into an elevated reservoir. The water is then released from the reservoir, flowing through penstocks and to turbines which power a generator to produce electricity. 

What Are Currently the Different Types of Nuclear Energy

In general, nuclear power is generated when neutrons either divide or fuse, which releases heat, produces steam, spins a turbine, and drives generators to produce electricity. 

The two ways we can generate nuclear power are via nuclear fission (when neutrons divide) or nuclear fusion (when neutrons fuse).

Nuclear fission is the generation of energy produced when splitting apart the nucleus of an atom. 

“Nuclear fission: a nuclear reaction in which a heavy nucleus splits spontaneously or on impact with another particle, with the release of energy.”

Cambridge Dictionary

Nuclear fusion is the generation of energy produced when lighter atoms are combined or fused to create larger and heavier atoms.

“Nuclear fusion: the process of joining two nuclei to produce energy.”

Cambridge Dictionary

All operating nuclear power plants today utilize the process of nuclear fission, whereas nuclear fusion is still very much in the research and development phase. 

Final Thoughts

The early history of clean energy dates back thousands of years with primitive methods of harnessing the sun, wind, heat from the earth’s core, tides, waves, and radioactivity. Scientific advances in the 1800-1900s paved the way for the development of modern clean energy technologies.

The establishment of the International Energy Agency (IEA) and the International Renewable Energy Agency (IRENA) have helped to develop the clean energy industry, which today generates over 6,700 TWh of clean energy. 

Clean energy is poised to see continued growth in the future as we look to reduce greenhouse gas emissions to levels stated in the Paris Agreement. Ambitious government targets, policy support, increasing competitiveness of clean energy companies, and decreasing costs will heavily influence the future of clean energy.

Stay impactful,

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