Electricity and Energy Sources

Where does the energy that powers our world come from? According to the First Law of Thermodynamics, energy can neither be created nor destroyed, only converted from one form to another. So when you charge your phone, turn on a light, or refrigerate food, where is that electricity coming from? Let’s start with the basics.

Electricity is a product of energy conversion, typically done using turbine generators. Like blowing on a pinwheel to make it spin, the blades of the turbine rotor are made to spin from the force of water, steam, gas, or wind. This creates mechanical energy (energy from motion), which the generator converts into electrical energy (energy from charged particles).

Other electricity generators include solar photovoltaic (PV) cells, also known as solar panels, and internal combustion engines. Solar PV cells convert sunlight directly into electricity without the use of a turbine. Internal combustion engines have many purposes, but they are most commonly known for their use in cars. In these, fuel is mixed with air and the mixture is ignited to create energy for the vehicle to run.

While many forms of electricity generators exist, they all share a common feature: they require an energy source. Energy sources are classified as either renewable or non-renewable. As the name implies, renewable sources are naturally replenished. Solar energy, wind energy, hydropower energy (from moving water), geothermal energy (from heat inside the planet), and biomass energy (from plants) are all examples of renewable energy sources. Non-renewable energy sources have a limited supply because they are extracted from the earth. These include coal, natural gas, and petroleum (often called fossil fuels), as well as nuclear energy, which is produced from the rare element uranium.

Source: Byjus.com, “Sources of Energy”

In 2021, non-renewable energy sources were used to generate 71.2% of the electricity used across the globe, with fossil fuels accounting for 61.4%. Fossil fuels have been the main source of energy for around 200 years, meaning nearly every piece of technology was designed with them in mind. Alongside their convenience and efficiency as a fuel source, it’s no wonder why coal, oil, and gas are so widely used today as an energy source. However, they are also the largest contributor to global climate change, accounting for nearly 90% of all carbon dioxide emissions.

To lower the impacts to the environment and its inhabitants (that includes us!), we need to transition to cleaner, renewable energy sources. According to the United Nations, approximately 80% of the global population depends on fossil fuels from other countries, meaning political crises can put them at risk. Renewable sources, on the other hand, are readily available everywhere. Renewable energy is also the cheapest energy option in most places. From 2010 to 2020, solar power prices fell by 85%, and wind energy prices fell by about 50%. In the workforce, a substantial increase in energy sector jobs would accompany the transition to renewable sources. Further, in 2018, the World Health Organization (WHO) stated that air pollution from fossil fuels caused $8 billion in health and economic costs per day, finding that 99% of people in the world breathe air that threatens their health.

Transitioning from non-renewable energy sources benefits everyone, including the animals and ecosystems that depend on our choices. In December of 2022, IEA stated that the global energy crisis pushed the change to renewable sources, “with the world set to add as much renewable power in the next 5 years as it did in the past 20”. Hopefully, this momentum will continue for years to come and push the world to incorporate renewable energy sources into everyday technology.

References

Alternative Fuels Data Center. (n.d.). Electricity Production and Distribution. Energy Efficiency and Renewable Energy. https://afdc.energy.gov/fuels/electricity_production.html

IEA. (2022, December). Renewable Power’s growth is being turbocharged as countries seek to strengthen energy security - news. IEA. https://www.iea.org/news/renewable-power-s-growth-is-being-turbocharged-as-countries-seek-to-strengthen-energy-security

U.S. Energy Information Administration. (2022). Sources of Energy. What is Energy? https://www.eia.gov/energyexplained/what-is-energy/sources-of-energy.php

U.S. Energy Information Administration. (2023). Electricity Explained. https://www.eia.gov/energyexplained/electricity/

United Nations. (n.d.). Renewable energy – powering a safer future. United Nations. https://www.un.org/en/climatechange/raising-ambition/renewable-energy

WED. (2023, June). World Final Energy. World Energy Data. https://www.worldenergydata.org/world-final-energy/

World Health Organization. (2018, December). COP24 special report: Health and climate change. World Health Organization. https://www.who.int/publications-detail-redirect/9789241514972