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Ammonia for Energy Storage and Delivery

The Advanced Research Projects Agency (ARPA-E) funds high risk, high reward transformational research to reduce energy related emissions, reduce imports of energy from foreign sources, improve energy efficiency across all economic sectors, and ensure US technological lead in advanced energy technologies, including electrochemical energy storage and transformation for grid scale and automotive applications. Storing energy in the form of liquid fuels has numerous advantages compared to conventional methods of energy storage (ES) such as batteries (high cost, short cycle life), pumped hydro and compressed air (low energy density). Low costs of storage and transportation of liquid fuels enables long-time ES…

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Investigating and Understanding Ionic Ammine Materials

Ammonia has been promoted as a viable candidate as an indirect hydrogen fuel vector, due to its high hydrogen content (17.8 wt%) and its ability to store 30% more energy per liquid volume than liquid hydrogen [1]. Ammonia can be safely stored in very high gravimetric and volumetric density in solid state halide materials [2-3], for example, at 109 gL-1 for Mg(NH3)6Cl2 compared to 108 gL-1 for liquid ammonia. These solid state ammonia coordination complexes, known as ammines, have attracted much recent attention (for examples see [4-5] and references there within) with a view to their use as solid state…

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Using Renewable Energy to Produce NH3

Commercial production of Ammonia (NH3) is a large scale industrial process converting natural gas (or other fossil fuels) into gaseous hydrogen, which is catalytically reacted with nitrogen to form anhydrous liquid NH3. NH3 made from natural gas is responsible for approximately 5% of global natural gas consumption (around 2% of world energy). Hydrogen can be produced more simply and more sustainably by the electrolysis of water using renewable electricity. Thus decoupling NH3 production from fossil fuels and substantially decarbonising the process. This provides a means of utilising intermittent renewable electrical power to produce NH3 for use as a fertilizer, fuel…

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Liquid Ammonia for Hydrogen Storage

Hydrogen storage and transportation technology is essentially necessary to realize hydrogen economy. Hydrogen can be stored in many different forms, as compressed or liquefied hydrogen in tanks, or as hydrogen carriers: a hydrogen-absorbing alloy, metal hydrides with light elements, organic hydrides and carbon-based hydrogen storage materials. Among them, solid-state hydrides with light elements such as MgH2, Mg(BH4)2 and NH3BH3 possess high hydrogen capacity, 7-20 mass%, However, the practical volumetric H2 density is below 8 kgH2/100L because the packing ratio is down to 50%. Ammonia is easily liquefied by compression at 1 MPa and 25°C, and has a high volumetric hydrogen…