Use of natural gas
75.37 billion cubic meters of natural gas was injected into the national gas pipeline network in 2019
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 is an environmentally friendly fuel. In fact, based on the same energy used, it 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.
Gas is an accessible source, given the presence of considerable reserves near Europe and the development of the liquefied natural gas global market which has increased availability at low prices.
Lastly, 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. This is also thanks to a gas-based electricity generation capacity that is already widely available and extremely efficient.
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.
In 2019 a total of 75.37 billion cubic metres of gas was injected into the network, an increase of 2.55 billion cubic metres (+3.5%) compared with 2018.
The increase was mainly as a result of higher consumption in the thermoelectric power generation sector (+2.45 billion cubic metres; +10.1%) following greater use of natural gas in the generation of electricity, the reduction in electricity imports and the smaller production from renewable sources, particularly hydroelectric production, as well as the rise in wind and solar power.
The available storage capacity at 31 December 2019 of 12.5 billion cubic metres (+0.1 billion cubic metres compared with 2018, made available by the gradual entry into operation of the new Bordolano deposit), represents the greatest capacity offered at a European level, and was conferred in full for the 2019-2020 thermal year.
Volumes of gas moved through the storage system in 2019 amounted to 19.33 billion cubic metres, a fall of 1.74 billion cubic metres, or 8.3%, compared with 2018. The reduction was mainly attributable to lower withdrawals from storage (-1.26 billion cubic metres; -12.1%) mainly as a result of weather conditions.
During 2019, the Panigaglia (SP) LNG terminal regasified 2.40 billion cubic metres of LNG (0.91 billion cubic metres in 2018, +1.49 billion cubic metres). In 2019 57 methane tankers were unloaded (+36 compared with 2018).
The significant increase in volumes of activities compared with last year, is mainly due to the greater competitiveness of the cost of LNG compared with natural gas, as well as the new regasification capacity allocation mechanisms through dedicated auctions.
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.
Un recente studio Ecofys promosso dall’associazione Gas for Climate, di cui Snam fa parte, ha stimato che lo sfruttamento del gas rinnovabile potrebbe portare un risparmio complessivo a livello europeo di circa 140 miliardi di euro all’anno entro il 2050, rispetto ad uno scenario che escluda l’utilizzo del biometano.
27 May 2020 - 16:31 CEST