Energy Networks Australia has just released a report which confirms that the injection of hydrogen into the gas distribution network can be achieved under current gas legislation.
Hydrogen is the most abundant chemical element in the universe and the third most abundant element on the Earth’s surface. It is a clean burning fuel that only produces water vapour during combustion.
The report, Gas Vision 2050, was conducted by law firm Johnson Winter & Slattery and states that hydrogen can be used as a supplement, or as an alternative, to methane in gas networks or in fuel cells to generate heat or electricity. This can provide energy for vehicles, homes or commercial buildings.
Hydrogen is not new as a gaseous fuel
Prior to the introduction of natural gas, town gas – produced from coal – was distributed in towns and cities and was first used in Australia in 1841. This fuel was made from a variety of raw materials (usually coal) and comprised 50 to 60 per cent hydrogen. The conversion to natural gas began in Adelaide, Brisbane and Melbourne in 1969 and then in Sydney in 1976.
The conversion to hydrogen networks is driven by the need to reduce greenhouse gas emissions
While the direct use of natural gas already has one-quarter to one-sixth the emissions of grid-based electricity in coal-powered states, Gas Vision 2050 states that in the longer-term, even those emissions may need to be reduced. It confirms that carbon reductions may initially be achieved by blending biogas with methane in existing plastic natural gas distribution networks. Further emissions reductions could occur by increasing the proportion of biogas or blending with hydrogen in networks resulting in a mixture of natural gas, biogas and hydrogen.
The report also notes that hydrogen volumes of up to 10 per cent are already being injected in the network in Germany without modifications to the network or appliances.
If required for greenhouse gas emission reductions, entire networks may need to be converted to pure hydrogen or mixtures of hydrogen and biogas in the long-term. The report highlights that this may require some modifications to existing gas appliances, but a suitable transformation program could be developed to reduce costs or impacts on consumers.
Today hydrogen is commonly produced from natural gas
Cities around the nation have natural gas delivered through long-distance transport of gas (e.g. transmission pipelines or even LNG tankers), so the report affirms that adding production facilities at cities’ edges to produce hydrogen, and injecting the hydrogen into the distribution system, is ‘easily achievable’. Alongside this, any carbon dioxide by-product could be stored securely through carbon capture and storage or used in the production of other materials.
The report outlines these innovations create the potential for clean, dispatchable energy, resulting in zero emissions while utilising existing infrastructure.
An alternative is to produce hydrogen using electrolysis powered by excess renewable energy
With generation from renewables unlikely to coincide with demand from energy users, efficient storage solutions will be essential. The report notes that unused energy generated by renewables could be converted to hydrogen through power-to-gas technology. The hydrogen could then be stored in the gas network. In these systems, surplus renewable energy can be used to electrolyse water. These systems then release pure hydrogen – which can be injected and stored in existing networks thereby avoiding expensive new batteries.
Energy Networks Australia CEO Andrew Dillon said the findings from the report would help inform work on the National Hydrogen Strategy.
“There are already trials under development by gas distributors that aim to blend renewable hydrogen into existing gas networks,” Mr Dillon said.
“Hydrogen can play an important role in not only helping Australia’s gas networks decarbonise – but as energy storage. Flexible hydrogen production can help soak up excess renewable electricity on sunny and windy days, then fuel cells can generate emissions-free power on still evenings.”
Hydrogen has the potential to widen customers’ power options, improve and increase renewable generation, provide options for mobility and even create a new energy export market. Mr Dillon believes that funding for research and development, backed by bipartisan national support, will drive the commercialisation of hydrogen technologies.
“Establishing a strong, domestic hydrogen industry will allow for the development and acceleration of Australia’s hydrogen export industry,” he concluded.