In our pursuit of sustainable and clean power generation, renewable energy sources are taking centre stage. Among the methods available, four stand out for their contribution to the global energy mix. Here we share the top renewable energy sources powering a sustainable future.
Energy (electricity, heat, and transport) accounted for around 73% of global emissions in 2020, presenting a huge opportunity to reduce global emissions. Renewable energy solutions provide clean, low carbon energy from methods which are freely available without limit, unlike fossil fuels which are highly polluting and extracted from a finite supply.
Although nuclear energy is a low-carbon option and offers the potential to replace oil as a readily available and high output energy source, it doesn’t fall under the category of “renewable” and is accordingly excluded from this particular list.
Moreover, in this list we look at renewable electric producers specifically, so while biomass and biogas are seen as renewable, their main use comes in the form of cooking and heating rather than electricity production.
Capacity vs generation
This article introduces values like megawatts (MW) and Terawatt-hours (TWh) to highlight the distinction between a power generation system’s capacity and its actual output. Changes in output are caused by factors such as weather conditions, maintenance requirements, and system inefficiencies.
Onto the list.
Geothermal Energy
Tapping into the Earth’s depths, geothermal power plants extract fluids from underground reservoirs to produce steam, which then drives turbines to generate electricity.
The first commercial geothermal power plant was built in Larderello, Italy, in 1904, and as of 2020, geothermal has a global energy capacity of 14,075 megawatts (MW). To put this into perspective, the combined power output of geothermal for a year could power approximately 1.2 million homes.
Leading the charge with geothermal are countries like the United States (2,587 MW), Indonesia (2,131 MW), and the Philippines (1,928 MW).
Additional facts:
- Comes at a levelised cost of energy (LCOE) of around $0.07 per kilowatt-hour (kWh)
Wind Energy
Harnessing global winds to drive turbines and generate electricity, wind energy has been used for centuries for sailing and pumping water uphill. The first wind turbines were built in the 19th century, and today wind has established itself as a prominent player in the renewable energy space, boasting a global capacity of 824 GW in 2021.
China leads the wind energy revolution with an astounding 328 GW capacity, followed by the United States (132 GW), and Germany (63 GW). Denmark deserves a special mention, as wind energy contributes an impressive 22% to its overall energy mix.
Wind energy can be categorised into two variants: onshore and offshore.
Additional facts:
- Onshore wind has an LCOE of $0.03/kWh
- Offshore wind has an LCOE of $0.08/kWh, reflecting the additional infrastructure required beneath the waves and maintenance
- In 2019, wind energy accounted for approximately 2% of global energy production
Solar Energy
Harnessing the sun’s endless potential through photovoltaic (PV) cells or concentrated solar power (CSP) systems, solar energy has experienced remarkable growth in capacity over the past decade. The first solar cells were developed in the early 20th century, and in 2021, globally, solar capacity reached 843 GW.
Generating a total of 1290 Terawatt-hours (TWh) in 2022, solar could have powered all of the homes in the United States for about 1 year.
China leads the solar revolution with an astonishing 306 GW, more than three times that of the United States at 93 GW. With the US Inflation Reduction Act looking to accelerate the adoption of renewable energy solutions, this will likely grow substantially over the coming years. Special mention should also be made of Chile’s adoption of solar as a renewable energy source, where it now accounts for over 17% of the countries entire energy mix.
Additional facts:
- Solar has an LCOE of $0.05/kWh
- In 2019, solar accounted for approximately 1% of global energy production
Hydropower
Harnessing the force of water to turn turbines, hydropower plays a pivotal role in the renewable energy mix and is the overwhelming champion in global generation. The first hydroelectric power plant was built in Appleton, Wisconsin, in 1882, and in 2022, it produced a huge 4,323 TWh, enough to power 432.3 million US homes for 1 year.
China leads in hydropower generation, producing 1,318 TWh, with Brazil following suit at 428 TWh. Notably, Norway and Iceland have embraced hydropower remarkably well, with it accounting for 65.91% and 61% of their energy mixes, respectively.
Additional facts:
- Hydro has an LCOE of $0.05/kWh
- In 2019, hydropower accounted for approximately 7% of global energy production
Final thoughts
Renewable energy is vital for a cleaner, brighter future. The latest report from the IPCC highlighted the technology’s role in limiting global warming along with the benefits such as reducing energy security risks, improving air quality, and creating new jobs.
However, some renewables have limitations. They rely on unpredictable factors like wind and sunshine, resulting in inconsistent energy production. This is where storage solutions become crucial. They store excess energy generated during peak times for later use when production decreases.
That’s why, in the short term, we still need “reliable” fuel sources like oil, gas, and nuclear power to ensure a continuous power supply. As renewable energy and battery storage technologies advance, nonrenewable methods will gradually phase out.
