Are synthetic gasses the replacement for fossil fuels?

Rinnai UK’s Operations Director Chris Goggin explains what synthetic gasses are being developed and produced as a possible replacement to natural gas. 

Since the North Sea gas fields were located in the 1970s, the UK has, until recently, been reliant on fossil fuels. To distribute gas into domestic and commercial premises 176,000 miles of pipeline infrastructure have been installed across the UK. This subterranean energy distribution network provides 40% of our total energy consumption in the form of natural gas, with 85% of UK buildings using natural gas for their heating and hot water.  

Today, natural gas remains the prominent domestic and commercial power option. In terms of societal behaviour and infrastructure, however, the UK is well prepared for any move away from natural gas towards an alternative gaseous fuel that fulfils modern operational and ecological requirements.  

Work to identify potential future gasses have revealed a number of options that are compatible with the UK’s infrastructure. A low-carbon gas that can be accepted by current pipelines and behave in a similar, if not identical, manner to fossil fuels is the ideal replacement. Among the list of these potential replacements are e-methane and biomethane. E-methane is the name given to synthetic methane or renewable methane – a gas created by extracting captured carbon dioxide and blending it with green hydrogen, itself produced via renewable energy. Green hydrogen electricity is converted into a storable low carbon gas – e-methane. 

Biomethane is produced in a separate process; methane is captured from natural biological waste and forms during a natural process called ‘anaerobic digestion’.  In the absence of oxygen, microorganisms will begin to break down matter, yielding methane gas. Once impurities are removed the methane gas becomes upgraded and biomethane is created. Both biomethane and e-methane are capable of identical operating behaviour when compared to fossil fuels and can therefore be placed into existing infrastructure. They could immediately fulfil the role of fossil fuels without any fracture towards appliance operating efficiency, commercial activity, or societal cohesion. 

Synthetic natural gas (SNG) is an umbrella term for a variety of gasses that behave and perform very similarly to natural gas. SNG can be produced either using biomass or renewable power. Any gas that is generated via biomass or renewable energy is referred to as Biogas, e-gas, and syngas. If a gas is created using waste such as manure, the gasification process of production is known as biochemical SNG production. If the process of gas manufacturing involves hydrogen that is renewably produced, then that (SNG) gas derives from a production concept named Power-to-Gas or Power-to-X. These ingredients and production approaches birth end-product e-gas/syngas.  

Syngas is potentially interchangeable with any appliance that has previously accepted natural gas. Liquified or compressed Syngas can also be potentially transported through any functioning gas grid for usage or export and can be stored in the exact same environment as natural gas for identical durations of time. 

Raw materials required for the creation of syngas arrive in the form of either fossil fuels or bio-waste. These materials are used to create a feedstock which is then inserted into a gasifier in either dry or slurry form. Once inside a gasifier that is low on oxygen the feedstock reacts with steam at a high pressure and temperature. This process creates syngas that is comprised of carbon monoxide, hydrogen and lesser amounts of methane and carbon dioxide.  

Although UK public and political confidence in hydrogen requires work, the UK government has recently announced that £500 million of funding will be provided towards new hydrogen infrastructure projects. This funding will stimulate regional hydrogen usage in transport, as well as storage networks that link hydrogen manufacturers, industrial end-users, and power stations.  

Once the UK likely eradicates fossil fuels from the domestic energy mix, a substitute gas will have to be introduced to provide domestic and commercial premises with heat as well as hot water in areas that are economically, practically and technically difficult to electrify. The task is to identify a singleg candidate that is accepted by customers, environmental lobbies, and politicians alike. 

www.rinnai-uk.co.uk