Use of natural gas
69.97 billion cubic meters of natural gas was injected into the national gas pipeline network in 2020
A gas-powered combined cycle with an output of 56-58%, makes it possible to reduce CO2 emissions by 62% compared with a coalpowered plant.
For the same energy input, the carbon dioxide produced by the combustion of natural gas is 25-30% less than oil products
Natural gas, based on the same energy used, has a lower polluting impact compared to other fossil fuels.
Natural gas helps to reduce atmospheric emissions by replacing polluting fossil fuels and reducing problems of air quality, acid rain and greenhouse gas emissions (GHG). Natural gas is mainly composed of methane (CH4) and the main products resulting from its combustion are carbon dioxide (CO2) and water vapour, the same components that are produced by breathing.
For the same energy input, the carbon dioxide produced by the combustion of natural gas is:
- 25-30% less than oil products
- 40-50% less than coal.
Coal and fuel oil are composed of very complex molecules with high carbon, nitrogen and sulphur content. This means that, during combustion, coal and oil release higher levels of harmful emissions (carbon, nitrogen oxides – NOx – and sulphur dioxide – SO2) and unburnt particles compared to natural gas.
The combustion of natural gas, on the other hand, releases small amounts of sulphur dioxide and nitrogen oxides, does not generate ash emissions or particulates, and emits low levels of carbon dioxide, carbon monoxide, and other reactive hydrocarbons.
The decrease in emissions per unit of energy produced is further accentuated by the possibility of using natural gas in high-performance applications and technologies, such as condensation boilers, co-generation plants and combined cycles for producing electricity. A gas-powered combined cycle with an output of 56-58%, compared with an output of about 40% from traditional steam-powered cycles, makes it possible to
reduce CO2 emissions by 52% compared with a traditional fuel oil-powered plant and by 62% compared with a coalpowered plant.
The electrification of consumption and the development of renewables accentuate some critical issues in terms of load: the entire gas system will therefore be called upon to provide ever greater flexibility to ensure the stability of the electricity grid with a sector coupling perspective.
Actually, the gas system can count on existing transportation, storage and distribution systems and is capable of supporting Italian and European decarbonisation guaranteeing the energy system flexibility, programmability and cost effectiveness.
GAS AND TECHNOLOGICAL INNOVATION FOR FIGHTING CLIMATE CHANGE
Power to Gas
The natural gas network can play an essential part in managing the ever-increasing volumes obtained from renewable sources. The excess electricity produced by solar power stations or wind farms can actually be converted into hydrogen through an electrolysis process and then enriched with CO2, making it possible to produce a syngas to be injected into the network. This avoids investment costs in new infrastructures for the transmission, distribution and storage of electricity.
In Italy, for over 70 years so-called town gas, made up of mixtures with 50% hydrogen content has been distributed in cities without problems.
Europe is keeping a careful eye on the new technology, which has already been included in the German national energy programme.
Gas-powered Heat Pumps
This is a technology that makes it possible to combine the many advantages of natural gas with the operating principle of heat pumps. Thanks to the exploitation of ambient heat, which is renewable and free, it is actually possible to improve output compared with normal condenser gas boilers. Output indicates the useful energy produced with the gas energy used.
The optimum output of a condenser boiler is equal to approximately 110%, but with gas-powered heat pumps it is possible to achieve a figure of up to 170%.
To shape the results of studies and research conducted at national and international level in the hydrogen field, Snam has created a new business unit dedicated to hydrogen, with the aim of evaluating possible pilot projects and contributing to the development of the supply chain. In parallel, studies will continue on the adaptation of compression and storage infrastructures and on the role of hydrogen in the future energy system also with a view to collaboration between different sectors (sector coupling), such as the electricity and gas sectors.
In particular, in April 2019, Snam experimented the introduction of a mix of 5% hydrogen and natural gas in its transmission network, replicating the experiment in December, in the same point of the network, bringing the amount of hydrogen to 10%.
The national gas pipeline network helps meet the country’s energy demand.
The gas injected into the network in 2020 totaled 69.97 billion cubic meters, down by 5.40 billion cubic meters compared to 2019 (-7.2%).
Total storage capacity as at 31 December 2020, including strategic storage, was 17.0 billion cubic metres (unchanged with respect to 2019), of which 12.5 billion cubic metres related to available capacity fully allocated for the thermal year 2020-2021 and 4.5 billion cubic metres related to strategic storage.
Volumes of gas moved through the storage system in 2020 amounted to 19.60 billion cubic metres, an increase of 0.27 billion cubic metres, or 1.40%, compared with 2019. Greater disbursements to deal with the reduction in injections to the national network were partially compensated for by lower injections in storage.
During 2020, 2.52 billion cubic metres of LNG were regasified at the LNG terminal in Panigaglia (SP) (2.40 billion cubic metres in 2019; +5.0%) with 60 methane tankers unloaded (+3 with respect to 2019; +5.3%).
Biomethane nowadays and in the future
Biomethane is a renewable, flexible, efficient and programmable source, also thanks to existing transport and storage infrastructures, which are perfectly and totally integrated with other renewable sources like solar and wind energy.
Dedicated plants produce both agricultural and agro-industrial by-products from anaerobic digestion and organic fraction of waste through a biogas upgrading process.
Bio methane can already be injected into the network and used in all sectors where the gas is present. Because it is a renewable energy, on March the 2nd 2018 the Italian government issued a Ministerial Decree which promotes the use of bio methane as a fuel for road transportation.
An Ecofys study promoted by the Gas for Climate association, of which Snam is a member, estimated that the exploitation of renewable gas could lead to overall savings at European level of about 140 billion euros per year by 2050, compared to one scenario that excludes the use of biomethane.
29 April 2021 - 11:52 CEST