Natural gas is a versatile, clean-burning, and efficient conventional energy source that is used in a wide variety of applications, such as electric power, heating and cogeneration, and other different industrial uses, among others.

The fastest-growing use of natural gas today is for the generation of electric power. Natural gas power plants usually generate electricity in gas turbines, directly using the hot exhaust gases of fuel combustion. Natural gas-fired plants are currently among the cheapest conventional power plants to construct and have greater operational flexibility than coal-fired power plants because they can be fired up and turned down rapidly. Because of this, many natural gas power plants were used to provide peaking capacity at times when electricity demand was especially high. However, as a result of the decline in natural gas prices, it is now increasingly used as a base and intermediate load power source in many places.

Natural gas is used in buildings for space and water heating and for cooking. and can also be used to produce both heat and electricity simultaneously, a technology called “cogeneration”.

Natural gas can be used in a broad range of other uses in industry, as a source of both heat and power and as an input for producing plastics and chemicals, for the production of hydrogen gas production, mostly used to produce ammonia for fertilizer, and as a fuel.

Compressed natural gas has been used as a transportation fuel, mostly in public transit. In most cases, better use for natural gas in the transportation sector would be as a resource to generate electricity for plug-in vehicles or hydrogen for fuel cell vehicles.

For more information on the use of natural gas, I recommend the following materials prepared by me:

1 -The current situation and the perspectives of the energy sector in the European region, Chapter 1, Energy in Europe: Economics, Policy and Strategy; Nova Science Publishers, New York, USA; 2008.

2- Energy in Latin American and the Caribbean: The Current and Future Role of Conventional Energy Sources in the Regional Electricity Generation; ISBN 978-1-62081-899-2; Nova Science Publisher Inc; 2012.

3- Electrical Energy Generation in Europe: The Current and Future Role of Conventional Energy Source in the Regional Generation of Electricity, Springer, ISBN 978-3-319-08400-8, 2015.

4- Power Options: Energy Alternatives for the Future, Advances in Energy Research, Chapter 1, Vol. 22, Nova Science Publishers, ISBN 978-1-63483-230-4, 2016.

5- Conventional Energy in North America: Current and Future Sources for Electricity Generation; Elsevier; ISBN: 9780128148891; 6th June 2019.

6- Fossil Fuels: Current Situation and Perspectives of Its Use at World Level; Advances in Energy Research, Vol 31; Nova Science; ISSN: 2157-1562; 2019.

Good morning, Jorge,

that is a very comprehensive reply, but it does raise several questions.

1.0 Is there sufficient readily available natural gas in the world for future projections?

2.0 The next generation of large CCGT will have claimed outputs of roughly 1,600 MWe (gross) and efficiencies (LHV) of 63 to 65%. Do they have the flexibilities that you suggest in these larger sizes? Many have a cycling limitation. These large sets need large supply lines to transport high pressure fuel gas. They need correspondingly high compressor power. Electricity distribution will be complex, hence the decision making as to their location can be interesting and begs all many of questions around centralised vs distributed generation.

3.0 They all produce CO2 in large quantities (albeit less than coal fuelled establishments, even with IGCC).

4.0 With the impact of global warming being very real, if we progress to the hydrogen economy what do we do with the CO2 that even natural gas produces?

5.0 Do methane hydrates enter your thinking? Can they be harvested? (Methane is a very aggressive greenhouse gas!)

There is a very big world out there and it will need very big thinking to sustain it. Observations, please, readily accepted.

Regards Stephen.

Dear Stephen,

Many thanks for your comments on my answer to your question. My answers to your new questions are the following: 1- The natural gas reserves at the world level, in 2015, were 6.599.418,2 billion cubic feet; in 2018 natural gas reserves were reported to be around 6.950.570 billion cubic feet. Considering the production level of natural gas, in 2015, in 124.966,2 billion cubic feet, the R/P production at the world level is 52,8. In 2018, natural gas reserves were higher than in 2015, and the production was reported to be 136.536,87 billion cubic feet, with an R/P of 50,9.

Taking into account a significant increase in the use of renewables energy sources for electricity generation at world level until 2050, the reduction in the use of oil, natural gas, and coal for this specific purposes, and the possible discovering of new shale gas reserves in the future, there is sufficient natural gas for a minimum of five more decades.

2 and 3- I have the opinion that large CCGT power plants will continue to have the flexibility that I mentioned in my comments. In France, for example, EDF uses CCGT power plants to improve the flexibility needed for electricity system reliability. According to EDF sources, at the Bouchain site in northern France, EDF is working with turbine manufacturer General Electric (GE) to build a new-generation CCGT. The new CCGT power plant, equipped with state-of-the-art technology, will achieve record efficiency and thereby further reduce atmospheric emissions:

· 62% efficiency compared with 58% for a conventional CCGT and 37% for a conventional coal-fired power plant;

· CO2 emissions 10% lower than those of a conventional CCGT and 55% lower than those of a conventional coal-fired power plant, and reduced atmospheric emissions of other gases (nitrogen oxide: 50 mg/Nm3)

It will also offer greater flexibility:

· Maximum power reached in less than 30 minutes, with a ramp rate of more than 50 MW per minute, nearly double the current rate;

· Load reduction of up to 40% while complying with emission guarantees

4- At the moment, there are three types of hydrogen. One type of hydrogen is the one produced industrially from natural gas, which generates significant carbon emissions. That type is known as “grey” hydrogen. A cleaner second type of hydrogen is the so-called “blue” hydrogen, for which the carbon emissions are captured and stored, or reused. The cleanest type of hydrogen is the so-called “green” hydrogen, which is generated by renewable energy sources without producing carbon emissions.

5- According to Geology.com, as natural gas from shale becomes a global energy game-changer, oil and gas researchers are working to develop new technologies to produce natural gas from methane hydrate deposits. This research is vital because methane hydrate deposits are believed to be a more abundant hydrocarbon resource than all of the world's oil, natural gas, and coal resources combined. If these deposits can be efficiently and economically developed, methane hydrate could become the next energy game-changer. Enormous amounts of methane hydrate have been found beneath Arctic permafrost, beneath Antarctic ice, and in sedimentary deposits along continental margins worldwide. In some parts of the world, they are much closer to high-population areas than any natural gas field. These nearby deposits might allow countries that currently import natural gas to become self-sufficient. The current challenge is to inventory this resource and find safe, economical ways to develop it.