2017100018 07 Jan 2017 1 AUSTRALIA Patents Act 1990
COMPLETE SPECIFICATION
Using Renewable Ammonia as a Strategic Energy Reserve for Australia’s Defence
The following statement is a full description of this invention, including the best method of performing it as known to me: 2 2017100018 07 Jan 2017
Using Renewable Ammonia as a Strategic Energy Reserve for Australia’s Defence FIELD OF THE INVENTION (01) The present invention relates broadly to a method of using renewable ammonia as a strategic energy reserve for Australia’s defence.
BACKGROUND TO THE INVENTION (02) Defence of the Australian homeland requires the Australian Defence Force (ADF) and Australian industry and community which support it, to have ready access to resilient and locally produced supplies of energy for stationary and mobile use in both peace and wartime. (03) Australia is well supplied with indigenous energy resources of coal, gas and renewable energy for stationary electricity generation at large population centres with dedicated electricity generating facilities. (04) Flowever when it comes to liquid energy requirements for mobile vehicles and for remote, off grid usage, Australia largely relies on imports of oil based petrol and diesel much of which is imported from refineries based in Singapore. (05) Currently Australia’s net reserves of oil are well below the 90 days required by Australia’s membership of the International Energy Agency. (06) Historical experience with the fall of Singapore in the early stages of the Second World War serves to highlight the strategic challenge inherent in Australia’s lack of indigenous supplies of liquid fuel for defence and industrial purposes especially in wartime. (07) Coupled with the immediate strategic issues highlighted above, is the need for Australia, along with the rest of the world, to decarbonise its energy supplies in response to the challenge of climate change. (08) Whilst most global ammonia (NFI3) production is based on fossil fuel feed stocks, of recent times there has been growing awareness that liquid NFI3 can be produced from carbon free renewable sources using renewably powered water electrolysis for hydrogen (H2) and renewably powered air separation units for nitrogen (N2) and renewably powered gas synthesis and liquefaction. (09) Because of its very high volumetric and gravimetric density of H2, liquid NH3 can act as an extremely efficient storage and transport vector for hydrogen as energy. 3 2017100018 07 Jan 2017 (10) In terms of volumetric density, which is a crucial determinate for the economics and logistics of long distance transport, a one cubic meter tank of 700 bar H2 will contain 39.6 kgH2 and the same volume tank holding liquid H2 will hold 71 kgH2 but the same volume tank of liquid NH3 will hold 121 kgH2. (11) Once NH3 is contained as liquid in tanks at moderate cold temperature or pressure, it can be stored for years if required and at a fraction of the cost and volumes required to store H2 in either pressurized or liquid form. (12) NH3 is also seen as a convenient carrier of H2 because the world currently produces, transports, stores and consumes many millions of tonnes pa of NH3, which is handled by a vast existing infrastructure of ships, road and rail carriers, pipelines and storage tanks. (13) The storage, distribution and handling of NH3 is very similar to that of Liquid Petroleum Gas (LPG) which is widely used internationally as a liquid fuel for motor transport and indeed many vessels and tanks used for transport and storage of LPG can also be used for NH3. (14) Whilst most of the world’s existing NH3 production is used for fertiliser, in recent years there have been advances in technologies which can harness NH3 for the stationary and mobile generation of energy. (15) Such technologies have included electricity generation via modified engines, gas turbines and stationary fuel cells, all of which can be powered by a feed of NH3 as fuel. (16) Still further technological advances have made it possible to efficiently split or crack NH3 back to its two constituent gases of N2 and H2, thereby releasing purified H2 for use in fuel cell vehicles such as the Toyota Mirai, the Hyundai Tucson and the Honda Clarity. (17) Increasingly defence forces around the world, including the ADF, are working on harnessing H2 as the energy source for a range of applications including for fuel cell vehicles, airborne and underwater drones and mobile and wearable fuel cells for in-field electricity generation and battery charging. (18) The US Army’s co development with General Motors of the Colorado ZH2 truck is one example of hydrogen fuel cell vehicles being developed for military application. (19) Challenges for military H2 energy applications revolve around the storage and transport logistics of H2 which is famously and expensively difficult to store and transport whereas NH3, as noted above, is an extremely efficient medium for handling H2, with NH3 being stored and transported in a manner similar to LPG. 4 2017100018 07 Jan 2017 (20) Innovation Patent number 2016101350 describes how the invention of a Distributed Energy Hub Powered by Renewable Ammonia (DEHPRA) enables the downstream use of NH3 as a carbon free energy source for both mobile and stationary power generation via both the hydrogen and battery/electric pathways. (21) Smaller scale DEHPRA units can be designed as skid mounted mobile units which the ADF can deploy to forward positions to be regularly supplied with liquid NH3 delivered in road tankers in the same way that NH3 (as fertilizer) is currently transported on roads in Australia and internationally. (22) An opportunity exists for Australia to harness its vast land mass and world leading renewable energy resources of wind, solar, geothermal and tidal power, to indigenously generate and store large reserves of liquid ammonia for subsequent use in powering a range of stationary and mobile applications for both the ADF and the Australian civilian community. (23) By using many regional locations throughout Australia with access to water (as the source of H2) and renewable wind and/or solar energy, a network of small to medium scale renewable ammonia production and storage plants can be established which will produce and store NH3 in volumes sufficient to act as a networked distributed strategic energy reserve for the ADF. (24) Avoiding the development of large centralised renewable NH3 production and storage centres in favour of a distributed network of smaller plants, mitigates risk of destruction of these energy reserves and production facilities in a wartime or terrorist attack. (25) Further, once a distributed renewable NH3 production and storage plant has been built and has operated for such time as to produce and store the ADF’s required energy reserves for that location, the plant can continue to operate at a very low marginal cost to generate NH3 for use in local military and civilian requirements which could include not only carbon free energy, but in some locations, carbon free fertilizer for cropping. (26) Further still, as Australia builds up its knowledge base and its industrial capacity in renewable NH3 production, it will lay the foundation for a large new zero carbon energy export industry which can grow in size to rival that of Australia’s Liquid Natural Gas export industry. (27) These last two points highlight the way in which a build up of renewable ammonia as a strategic energy reserve for Australia’s defence requirements will simultaneously support a broadening of Australia’s local and export industries. 2017100018 07 Jan 2017 5
SUMMARY OF THE INVENTION (28) According to one aspect of the present invention there is provided a method of using renewable ammonia (NH3) as a strategic energy reserve for Australia’s defence, by: a. Developing in Australia one or more distributed renewable ammonia production and storage plants by using renewable energy to generate hydrogen and nitrogen and to power a synthesiser and liquefaction unit so as to produce renewable NH3 in liquid form and locating at or nearby to such production facility, cold storage or pressurized tanks which can store liquid NH3; and b. Storing at such a plant, volumes of liquid renewable NH3 as required by the Australian Defence Force for contribution to its national strategic energy reserves; and c. Using communication and transport linkages to network two or more such renewable ammonia production and storage plants, such that the network constitutes a distributed strategic reserve of liquid energy to serve part at least of the energy requirements of the Australian Defence Force whilst avoiding the use of a large centralised energy production and storage hub which could present a concentrated target for wartime or terrorist attack; and d. Distributing to military and civilian users such additional ammonia production from the plant which is surplus to the storage needs of the Australian Defence Force, where such users could use the ammonia for energy and or fertilizer purposes.