Energy Estate (in collaboration with various local and global energy players) is developing the Hunter Hydrogen Network (H2N), backbone infrastructure and core projects drawing on the existing industrial ecosystem of the Hunter and delivering competitively priced hydrogen and derivative products through and from the Hunter Valley. It will be Australia’s first “hydrogen valley” and will involve large-scale electrolysers in the Upper Hunter and a 120km dedicated hydrogen pipeline through the Hunter Valley. It will be supported by large-scale renewable energy generation from the Renewable Energy Zones in NSW and will enable downstream production facilities for various derivative productions (eg. Ammonia, e-fuels, methanol, liquid hydrogen etc), located in the lower Hunter Valley.

Having completed an initial scoping study for H2N, Energy Estate, with its collaboration partners, is continuing its development activity and preparing to undertake a feasibility study for the delivery of competitively priced hydrogen and derivative products in the Hunter.

Hydrogen is the most abundant element in the universe. However, naturally occurring atomic hydrogen is rare on earth since it readily combines with other elements to form molecules such as water, methane (natural gas) and methanol. Hydrogen is “produced” by breaking the chemical bonds in the molecules that form these substances. Today, most hydrogen is made from natural gas, some from electrolysis of water and some from bio-methane. Since Hydrogen can be made from many different sources, every region of the world has the potential to produce its own fuel, which ultimately benefits the environment and the local economy.

Historically, NASA has been the primary user of hydrogen resources for its space program—it fuelled the shuttles using liquid hydrogen and employs backup hydrogen fuel cells for electricity. In recent years, the focus has turned to Fuel Cell Electric Vehicles (FCEVs), which have lower greenhouse gas emissions than their gasoline counterparts. Hydrogen also has the potential to be used as stationary power (for buildings), backup power, storage of energy harvested through wind and solar processes, and as battery-like portable power (most commonly used in forklifts today).

Hydrogen is a very versatile and unique fuel that has many properties that would make it a perfect fuel for any advanced energy society. It is a zero-emission fuel, which means that using hydrogen does not create any emissions, greatly benefiting local health near roads, interstates and areas of high emissions like industrial centers or ports.

Hydrogen is an energy carrier like electricity, and can be produced from nearly any energy resource, including renewable resources like wind, solar, biomass, etc. and thus help create an energy economy that does not contribute to climate change.

Hydrogen fuel cells are silent operating, decreasing noise pollution in traffic and increasing the livability of communities. Hydrogen is scalable, and can power any vehicle in any size, from bikes to heavy-duty long-haul trucks, buses, ships and planes.

Refueling with hydrogen is fast, similarly to gasoline vehicles, and thus does not require a change in behavior by adopters of the technology.

Hydrogen fuel cells can be used safely indoors, e.g. large warehouses, and do not lose performance like batteries when they run near empty.

Hydrogen can be stored for long periods of time, unlike batteries which lose charge. Fuel cells do not degrade as fast when utilized over longer periods of time and different use-cycles, allowing them to be used for more than 10 years without requiring replacement. Hydrogen fuel cells are also fairly light on maintenance as they include very few moving parts.

Hydrogen, like electricity, is an energy carrier rather than an energy resource. Both electricity and hydrogen can be produced from all energy resources available (including, natural gas, petroleum products, coal, solar, wind, biomass, and others). Hydrogen and electricity can be made from GHG-neutral sources, addressing climate change and urban air quality problems. Also as with electricity, hydrogen can be made from sustainable domestic and renewable energy resources, which enhances our long term energy security.

Due to Hydrogen being an energy carrier, it is not consumed; it is only used. For example, hydrogen can be produced by splitting water (H2O) into two atoms of hydrogen and one atom of oxygen. The oxygen produced in this reaction is released into the atmosphere and the hydrogen is stored in a tank. This stored hydrogen can then be used to fill up a FCEV. When the FCEV is in operation, its fuel cell takes the hydrogen stored on board, as well as oxygen from the atmosphere, and produces electric power (to power the vehicle’s electric motors), water and heat. None of the oxygen, hydrogen and water is consumed in this process. The same amount of hydrogen, oxygen and water exist at the end of the process as at the beginning.

Today, 37%-44% of hydrogen used in transportation is renewable, but 95% of all hydrogen produced in the United States is made by industrial-scale natural gas reformation. This process is called fossil fuel reforming or steam methane reformation (SMR). The process takes natural gas (NG) and steam to generate a product stream of carbon dioxide (CO2) and hydrogen (H2). Large-scale SMR is an efficient process at more than 70% thermal efficiency. Most hydrogen is produced for chemicals and oil refining processes, in which more expensive renewable hydrogen is not desired.

Greenhouse gas emissions can be avoided completely if the CO2 produced in SMR is captured and stored, in a process known as carbon capture and storage (CCS). As sustainable renewable energy generation advances in the United States, it is anticipated low to zero carbon hydrogen production will become more commonplace.

More than 10 million metric tons of hydrogen are produced annually in the United States, which is enough to fuel tens of millions of FCEVs. The current primary uses for hydrogen, however, are for the petroleum, ammonia for fertilizer, chemical and food industries.

Hydrogen is an industrial raw material, and it can be combined with other things to create hydrogen-based fuels and feedstocks. There is already a market in hydrogen for various applications.

When we are talking about the potential for a hydrogen economy, we are talking about hydrogen in its pure form, where it is an energy carrier. Hydrogen stores energy which can be used at later times and can be transported to different places. In this way, hydrogen acts like a battery. However, unlike conventional batteries, hydrogen allows energy to be stored for long periods.

Hydrogen is versatile. It can be produced from a range of sources and physically converted between its gaseous and liquid states. It can displace natural gas for heating and cooking, and it can replace diesel and petrol (and other fuels) for cars, trucks, ships and planes. It can store excess electricity and feed this back into the grid when it is required. It can also be chemically converted into other forms, such as ammonia and methane. Hydrogen can be repeatedly converted across and between its physical forms and chemical forms.

When we combine these features with the possibility of hydrogen being created at scale with renewable or clean energy, we can see the great potential for hydrogen in the new energy ecosystem.

The International Energy Agency has identified around 70 million tonnes per year (MtH2/yr) of demand worldwide for “pure” hydrogen, where this is demand for hydrogen with only small levels of additives or contaminants. Hydrogen of this type is commonly used for refining oil and producing ammonia for fertilizer.

There is a further 45 MtH2/yr of hydrogen used in a mixture of gases, such as synthesis gas, for fuel or feedstock. This hydrogen is mainly used for producing methanol and steel. Most hydrogen used today is produced from fossil fuels.

Yes. Hydrogen is only as clean as its inputs.

But hydrogen does not have to come from fossil fuels; the technology to produce clean hydrogen through the application of electricity to water (called electrolysis) is well established. If the electricity used for the electrolysis is from renewable sources, such as solar and wind, the resulting hydrogen has zero carbon and is clean. Hydrogen can also be produced from fossil fuels with carbon capture and storage, which means that there are low to zero carbon emissions.

We expect that hydrogen producers in Australia will have to demonstrate how their hydrogen was made. This will mean showing whether the hydrogen was produced from electrolysis, fossil fuels, or other sources, and showing whether electricity and other inputs to the production were renewable. If hydrogen has been produced from fossil fuels, potential buyers will need to see if carbon emitted during the production process was captured and stored.

It will be important to get this right, particularly as so much of the value of the hydrogen economy is associated with clean energy. The countries which have expressed a desire to be major importers of hydrogen have done so to obtain clean hydrogen and Australia must ensure that it can meet its potential customers’ needs.

Traditionally hydrogen has been more expensive than conventional fuels to produce, store and transport. There are efficiency losses from converting electricity and natural gas to hydrogen, which make the case for hydrogen more challenging. It is also energy intensive to store and deliver.

The penetration of renewable energy is at unprecedented levels, and the costs associated with renewables have fallen significantly. Climate change has also resulted in an increased call to decarbonise the global economy, with many countries developing hydrogen strategies and plans to increase their production and/or use of clean hydrogen.

Hydrogen now has the potential to play a major part in the future energy mix.

Electrolysis is a process where an electric current is used to drive a chemical reaction. In the production of hydrogen, an electrolyser is used to apply electricity to water to split it into its components (hydrogen and oxygen). The hydrogen is collected and the oxygen is allowed to harmlessly escape.

Electrolysis is a well understood process and has been used in various applications for over 150 years. For hydrogen production it is a newer technology, at least for large-scale use. There are different types of electrolysers, with different costs and efficiencies, and these can be expected to improve over time.

'Clean' generally means there are very low to zero carbon emissions in the production of the hydrogen. This term covers hydrogen both with and without carbon capture and storage.

The colour terms denote the relative cleanness of hydrogen. Globally these terms are not consistent. In Australia:

Green hydrogen is carbon free: it is produced from renewable energy and non-fossil fuel sources.

Blue hydrogen is clean but not green: it is produced from natural gas but the carbon is not released into the atmosphere; it is captured and stored.

Brown hydrogen is not generally not clean: it is produced from fossil fuel sources (such as gas and brown coal) and the carbon is released into the atmosphere.

High-pressure natural gas (and hydrogen pipelines) today use steel alloys, while natural gas “distribution” pipes can be made of a variety of materials such as cast iron, copper, steel or plastic (PVC or PE).

A viable hydrogen infrastructure requires that hydrogen be able to be delivered from where it is produced to the point of end use, such as an industrial facility, power generator, or fueling station.

Hydrogen can be stored in three ways: As a compressed gas in high-pressure tanks. As a liquid in dewars or tanks (stored at -253°C). As a solid by either absorbing or reacting with metals or chemical compounds or storing in an alternative chemical form.

Hydrogen can be transported in pipelines. Hydrogen can also be transported by truck and rail in pressurised cylinders. For exports, there are many options being investigated with the three main shipping options being liquid hydrogen, ammonia or liquid organic hydrogen carriers. Methanol is also an option, but production requires a source of carbon-dioxide. Hydrogen is most commonly transported and delivered as a liquid when high-volume transport is needed in the absence of pipelines. To liquefy hydrogen it must be cooled to cryogenic temperatures through a liquefaction process. Trucks transporting liquid hydrogen are referred to as liquid tankers.

Storage of hydrogen in liquid form can be used for storing large quantities of gas for longer times, however at high-energy penalties for liquefaction. Metal hydrides may offer an advantage for storing small quantities of gas in the medium to long term.

Gaseous hydrogen can be transported through pipelines much the way natural gas is today. Approximately 1,600 miles of hydrogen pipelines are currently operating in the United States. Owned by merchant hydrogen producers, these pipelines are located where large hydrogen users, such as petroleum refineries and chemical plants, are concentrated such as the Gulf Coast region.

Transporting gaseous hydrogen via existing pipelines is a low-cost option for delivering large volumes of hydrogen. The high initial capital costs of new pipeline construction constitute a major barrier to expanding hydrogen pipeline delivery infrastructure. Research today therefore focuses on overcoming technical concerns related to pipeline transmission, including:

• The potential for hydrogen to embrittle the steel and welds used to fabricate the pipelines

• The need to control hydrogen permeation and leaks

• The need for lower cost, more reliable, and more durable hydrogen compression technology.

Potential solutions include using fiber reinforced polymer (FRP) pipelines for hydrogen distribution. The installation costs for FRP pipelines are about 20% less than that of steel pipelines because the FRP can be obtained in sections that are much longer than steel,1,2 minimizing welding requirements.

One possibility for rapidly expanding the hydrogen delivery infrastructure is to adapt part of the natural gas delivery infrastructure to accommodate hydrogen. Converting natural gas pipelines to carry a blend of natural gas and hydrogen (up to about 15% hydrogen) may require only modest modifications to the pipeline.3 Converting existing natural gas pipelines to deliver pure hydrogen may require more substantial modifications. Current research and analyses are examining both approaches.

Like other fuels, hydrogen is flammable. Hydrogen powered vehicles are on the roads in several countries and safety standards have been developed. Hydrogen is 14 times lighter than air, so any leak will rapidly diffuse into the air. However, there is still the risk of ignition, so specific safety features are installed at refuelling stations including hydrogen detectors.

If hydrogen is allowed to mix with air before it is ignited, this could lead to an explosion. However, should a release occur and it ignited immediately, no explosion would occur and the hydrogen would simply burn. Much care is taken to ensure that should such a leak occur, the hydrogen is vented to a safe location where it can burn out safely.

Hydrogen systems are designed to handle hydrogen leaks in a safe manner. Typical hydrogen storage systems are either pressurized or liquid. Liquid hydrogen is very cold and requires well insulated tanks to hold the hydrogen. These tanks are double walled vacuum sealed and are at low pressure. This is a very mature industry with decades of safe handling – the space shuttle uses liquid hydrogen. The handling of liquid hydrogen is and will be in the foreseeable future handled only by trained professionals. At a stationary storage facility, hydrogen can be stored under high pressure.