Natural Gas Case Study

Natural gas examples

Next, let’s talk about some natural gas examples.

Wet natural gas

Sometimes natural gas is mixed with other hydrocarbons that are heavier than methane, like propane, and when taken out of the ground have to be separated out to end up with just the lighter natural gas. The heavier hydrocarbons are the "wet" part making it wet natural gas. The leftover hydrocarbons can sometimes be turned into other products like petrol and liquified petroleum gas.

Dry natural gas

When the natural gas found in the ground is mostly methane, with little other hydrocarbons, it’s considered dry natural gas. The gas is under pressure, and long metal tubes are drilled into the ground to extract it. Because little processing is needed, dry natural gas is cheaper to extract.

Shale natural gas

Not all natural gas can be easily taken out of the ground. Natural gas is sometimes stuck within tight layers of rock known as shale and needs to be broken up through a process called hydraulic fracturing or fracking to extract it.

Liquified natural gas

Even though the name implies it's a gas, natural gas can also be cooled and compressed to take a liquid form. To stay in a liquid state, natural gas needs to be stored at very low temperatures and then ends up using much less space than when it’s stored as a gas. Because it takes less space, it’s much easier to transport efficiently, especially when taken over oceans where pipelines aren’t feasible.

Uses of natural gas

Natural gas has several primary uses, let’s talk about them below.

Electricity generation

As mentioned earlier, natural gas is highly flammable and is used to move a machine called a turbine, which generates electricity. As coal plants close down in developed countries, they are often being replaced by natural gas plants and renewable energy sources. Worldwide, about one-quarter of all electricity generated is from natural gas.

Heating

The heat from burning natural gas can also heat homes and buildings during cold weather. Natural gas heating is critical in Europe to heat places during the wintertime. Electricity is also used to heat buildings sometimes but generally is more expensive than gas in most places, including the UK.

Cooking

Natural gas also powers stove tops and ovens, providing heat for all manners of cooking. Due to the emissions they produce, gas stoves are sometimes coupled with ventilation systems that remove harmful gasses from the kitchen.

Fig. 2 - A burner is the most recognizable use of natural gas in everyday life

Transportation

While not very common, some vehicles are also powered using natural gas. Natural gas is usually cheaper than petrol, but these vehicles need more specialised equipment and space to store natural gas. Major investments in filling stations for natural gas are needed to make it a viable option in places where only petrol stations are found.

Advantages of natural gas

The main advantages of natural gas are that it is in abundant supply, can be used at will, and burns cleaner compared to other fossil fuels. Read on to learn more about each advantage in depth.

Abundant

Compared to other fossil fuels like oil, natural gas is more abundant, partly because it has not been exploited for as many years and also for geological reasons. Some countries are finding coal mining more and more expensive and are turning to their natural gas resources instead. While natural gas is a non-renewable resource, there are still significant quantities of it to meet power needs for the next several decades.

On-demand use

Like most non-renewable energy sources, natural gas can be stored and used as needed to generate electricity and heat homes. The advantage of this is that power generation and natural gas supplied for heating can be increased to exactly meet the needs of the people, and also decreased to save money and (potentially) reduce pollution.

Compared to renewable energy sources like wind and solar which rely on weather conditions like cloud clover and breezes, natural gas is only impacted by how much power a plant can produce and supply available. In effect, this makes natural gas a more reliable energy source, at least until more significant investments in renewable energy projects are made.

Burns cleaner

While the emissions from burning natural gas are by no means harmless, it does not contain the same amount of harmful pollutants that coal and oil products like petrol do when burned. Carbon monoxide is very harmful to human health, and there is next to none emitted when natural gas is burned compared to petrol. For coal power plants to achieve the same low level of pollutants as natural gas, expensive modern equipment is needed, sometimes making it so expensive that an older plant is closed in favour of natural gas to meet government regulations.

Disadvantages of natural gas

Now that we’ve gone over some advantages of natural gas, let’s look at the disadvantages of natural gas.

Greenhouse gas emissions

Natural gas is a fossil fuel that creates carbon dioxide emissions when burned, the primary driver of climate change. Additionally, natural gas is mostly methane, and methane is a strong greenhouse gas, over 25 times more potent than carbon dioxide. If natural gas is not stored properly, it can leak into the atmosphere, accelerating climate change.

Fig. 3 - Natural gas power plants like this one in Helsinki are leading contributors to climate change

Non-renewable

While we previously discussed that natural gas is plentiful, it’s still a non-renewable resource and is going to run out. Natural gas is not a permanent solution to our energy needs and will keep running out as the earth’s population increases and developing countries become richer. A switch to renewable energy is absolutely necessary for humanity to thrive into the future.

Pros and cons of natural gas

In short, the main benefit of natural gas is its ability to be used when needed for electricity and heating, and its main disadvantage is that it contributes to climate change and will eventually run out. The table below summarizes the pros and cons of natural gas.

Table 1