What are fossil fuels and their impact on climate change
Photo: National Geographic Society
What are fossil fuels?
Coal, petroleum and natural gas have been the main sources of energy for centuries, but the health of the planet has paid a heavy price.
Fossil fuels are in the news a lot these days — mostly because of our continuing efforts to replace them with more environmentally friendly sources of energy like solar and wind power.
The carbon emissions caused by the burning of fossil fuels are the main contributor to global warming. Of course, fossil fuels are also the main source of energy that has driven modern civilization for centuries.
Fossil fuels currently supply roughly 80 to 85 percent of the world’s energy. [1]
What are the types of fossil fuels?
There are three main types of fossil fuels: coal, petroleum and natural gas. Coal is cheap and abundant, but it releases a lot of pollutants when burned. Petroleum, or crude oil, is harder to find and is typically a bit cleaner-burning — and, unlike coal, it can be pumped through pipelines and easily refined into fuels like gasoline or kerosene. Natural gas is also relatively inexpensive and less polluting than coal or crude oil. [1]
Fossil fuels are found underground, trapped in deposits surrounded by layers of rock. Coal beds typically lie 60 to 90 metres below the surface. Oil and natural gas deposits are typically a mile or two down, and the deepest oil and gas wells have reached more than nine kilometres below the surface.
Photo: The Guardian
Fossil fuel deposits are found all over the world, but some countries have more than others. The United States, Russia and China have the world’s largest coal deposits. Roughly half of the world’s oil and natural gas reserves are located in the Middle East.
How are fossil fuels formed?
Fossil fuels are made up of carbon-containing (organic) molecules left over from plants and animals that lived and died millions of years ago. Most fossil fuel deposits were formed 540 million to 65 million years ago, when Earth’s climate was warmer and wetter, and its waters teemed with algae, bacteria and other tiny organisms.
Over tens of millions of years ago, the bodies of the once-living organisms became buried and compressed underground, forming a mineral called kerogen, or oil shale — the precursor of fossil fuels. Geothermal heat slowly transformed kerogen into fossil fuels, with some types of kerogens became coal and others crude oil or natural gas.
Photo: The New York Times
Advantages of fossil fuels
Fossil fuels are easy to obtain and cheap to use. And they have high energy density, meaning they yield high amounts of energy per kilogram when burned.
The Industrial Revolution of the 18th and 19th centuries was driven mainly by coal, which powered steam engines, factories, and foundries, while coal gas — a form of natural gas extracted from coal — was used for lighting, cooking and heating.
In the 20th century, oil, coal and natural gas became the primary fuels for electricity generation, and liquid fuels like gasoline, diesel fuel and kerosene became the motive power for cars, trucks, tractors, trains and aircraft.
Disadvantages of fossil fuels
Unlike wind and solar, fossil fuels are not renewable — and the vast fossil fuel reserves that still exist may one day be exhausted.
A more pressing concern is the environmental damage caused by the extraction and burning of fossil fuels. The carbon dioxide released by the combustion of fossil fuels is a leading cause of global warming.
In a 2018 report, UN climate experts warned that the world faces potentially catastrophic warming if emissions from fossil fuels can’t be drastically reduced [1].
Climate, Environmental and Health Fossil Fuels Impacts
The use of fossil fuel, coal, oil, and natural gas, results in significant climate, environmental, and health costs that are not reflected in market prices. These costs are known as externalities. Each stage of the fossil fuel supply chain, from extraction and transportation to refining and burning, generates externalities. [2]
Can fossil fuels be replaced?
While renewable sources of energy like wind, solar and geothermal are starting to replace fossil fuels in some places, they still meet only a small proportion of the world’s total energy demand.
It’s imperative that we must start changing our transportation technologies, and Hydrogen is a potential renewable energy source to start this transition.
We need to have government support to start the transition to a greener future now, not tomorrow.
Sources:
[1] NBC News, What are fossil fuels? – Retrieved from https://www.nbcnews.com/mach/science/what-are-fossil-fuels-ncna983826
[2] EESI – Environmental and Energy Study Institute, Fact Sheet | Climate, Environmental, and Health Impacts of Fossil Fuels (2021) – Retrieved from https://www.eesi.org/papers/view/fact-sheet-climate-environmental-and-health-impacts-of-fossil-fuels-2021#:~:text=Environmental%20Externalities,-Fossil%20fuels%20have&text=
Hydrogen Projects, Renewable Energy Engineer and Projects Development Manager at APW
Maddison S
Officer Assistant
