Natural gas


Natural gas is essential to guarantee energy supply in Spain and in Europe.


What is natural gas?

Natural gas is the fossil fuel that produces the least greenhouse gas (GHG) emissions and has the least impact on the environment. Its emissions are 40-50% lower than those of coal and 25-30% lower than those of fuel oil.

Its history goes back centuries. According to various studies on its origins, it dates back to 2,000 BC when the first natural gas deposits appeared in the territory that is now Iran.

Natural gas is produced beneath the earth’s crust by the decomposition of plant and animal matter over millions of years under anaerobic conditions, i.e. in the absence of oxygen.

It is used to generate energy for residential and commercial use (heating, hot water, cooking, etc.). It also works efficiently as a low-emission fuel for transport and as a raw material in industries such as in the petrochemical industry to produce ammonia, plastics, fertilisers, among others.




Types of natural gas

There are three types of natural gas:

Its natural state is gaseous and it is conserved at an ambient temperature of 20°C and an atmospheric pressure of 1 atm.

This is natural gas that has been processed so that it can be transported in a liquid state. It is subjected to a temperature of -160°C at an atmospheric pressure of 1 atm. It is used in energy-intensive processes, especially in mobility. In fact, it can be used for almost any type of mobility such as land, rail and sea.

Like natural gas, it is in a gaseous state at an ambient temperature of 20°C and an atmospheric pressure of between 200 and 250 atm. 



How is it obtained?

Natural gas is typically found at depths of between 1.5 and 4 kilometres, both onshore (below the earth) and offshore (under the seabed). Geological exploration makes it possible to identify deposits and then to extract them through drilling and pipeline systems.

Spain has no natural gas reserves and therefore imports almost all the gas it consumes from various sources. Thanks to having such a diversified supply, the Spanish Gas System, in addition to covering domestic demand, can export gas to other countries, thereby contributing to the security of energy supply throughout Europe.


How is it transported?

Once extracted from the fields, natural gas can be transported mainly via pipelines and methane tankers. These are its two main forms of procurement.

In the case of gas pipelines, the pipes are designed with materials such as steel and carbon, capable of withstanding high pressures and different temperatures with sufficient elasticity. The use of gas pipelines is ideal for covering long distances between the fields and the final destination of the natural gas. For example, between Almeria and Algeria there is a 200-kilometre undersea gas pipeline that contributes to guaranteeing energy supply, both to our country and to the rest of the continent.

Methane tankers are the ideal transport option when pipeline connections are not possible due to long distances between countries. They are designed to transport refrigerated natural gas at low temperatures (-160 °C). It then changes to a liquid state - known as liquefied natural gas or LNG - and takes up less volume.

On arrival at their destination, the vessels unload this LNG at the regasification plants. Once this process has been carried out, this gas:

  1. Once regasified, - returned to its gaseous state - it can be injected into the pipeline network for transport to its final destination or for underground storage.
  2. It can be loaded onto tanker trucks to reach territories that are not connected to the pipeline network.
  3. It can be stored in the same regasification plants for future supply, either through pipelines or through methane tankers that can refuel and take the gas to other countries.

Enagás is one of the companies with the most LNG terminals in the world. In Spain, it has four terminals located in Barcelona, Cartagena, Huelva and Gijón. It also has shareholdings in two others: 50% of the Bahía Bizkaia Gas (BBG) plant in Bilbao, and 72.5% of the Saggas terminal in Sagunto (Valencia).


Advantages of natural gas



Our natural gas services

At Enagás we offer our customers both the traditional LNG logistics services (tanker unloading, regasification, transferring LNG to tankers and truck loading) and new small-scale and bunkering services, for which we are constantly adapting our facilities. We also offer a vetting service for the assessment and inspection of methane tankers, both in large- and small-scale. 

Check all the types of natural gas and LNG services we provide.