What are fossil fuels?

A fossil is the remains of a prehistoric plant or animal that have become hardened into rock.

So when the word fossil is used to describe a fuel, it refers to fuel that has been formed from the remains of plants that died and decayed millions of years ago.

Since all plants contain carbon, just like wood they will all burn and release heat if they are dry enough. The same is true for the fossil fuels: coal, natural gas, and oil.  And because these fuels contain very little moisture, they burn much more fiercely than wood.

How much fossil fuels are there?  There’s a lot.

The oil company, BP, publishes a statistical review every year that shows the total proven reserves of oil, natural gas, and coal.  The table below shows the world’s proved reserves at the end of 2016, and the three countries that hold most of them:

World proven reserves of oil, coal, and natural gas (end 2016)

There’s no question that the harnessing of carbon-based fossil fuels has enabled mankind, not just to inherit the Earth, but to dominate it in ways unimaginable even a few centuries ago. Without plentiful supplies of energy from coal, oil, and natural gas, there is no way the Earth could have managed to support the almost 8 billion people who now live on it.

How long will fossil fuels last?

The BP statistical review calculates the ratio of proven reserves to current rates of production.  So that tells us about how long the reserves will last.

Oil – 50.6 years
Natural gas  – 52.5 years
Coal – 153 years

Pumping oil in West Texas

That’s at current rates of production.  Those could go up in the future as economies grow and the global population increases—or down, as more renewable energy starts to be used, coal fired power plants are phased out, and electric vehicles become more widely used.

And greater amounts of oil and gas may be found–since exploration by the major oil companies is continuing. So the total amount of proven reserves may also increase.

So what’s the problem?

When fossil fuels are burned—either to generate electricity in power plants or, as gasoline and diesel fuel, in the cars, trucks, trains, and aircraft that keep the global economy on the move—the carbon in the fuel combines with oxygen to form carbon dioxide—the principal component in the greenhouse gases that scientists believe are leading to global warming. Most scientists believe that we cannot continue to burn coal to generate electricity, and to fuel millions of cars and trucks with gasoline and diesel.

Which means that a lot of these reserves of coal, oil, and natural gas are going to have to remain where they are. In the ground.

And there’s another problem: combustion is never perfect.

The emissions from fossil fuel power plants and from the one and a half billion gasoline and diesel vehicles on the roads worldwide cause substantial amount of air pollution. Composed not only of carbon dioxide, but also minute particles of carbon, ash, and traces of other elements found in the carbon fuel, what is called particulate matter or just plain particulates is dangerous stuff.  When breathed in, it gets into the lungs and causes a host of respiratory problems—particularly for children.

Coal is the worst offender.  Several countries are now planning to phase out coal-fired power stations.


For more on the problems with coal go here
To know more about the oil sands in Canada go here.
To read about the problems with oil, go here
And to learn more about the hydraulic fracturing technology called fracking check out this page.