This paper defines hydrogen as ‘clean H2’ produced using renewable energy or using fossil fuels with
carbon capture and storage. From an industrial user perspective, H2 is a raw material or
intermediate in an overall production process regardless of where or how it is sourced. The cost of
the raw material impacts the cost of production. While process changes are less likely if H2 meets
the raw material specification, it depends on each plant, how easy the integration will be, and what
equipment modifications would be required. However, if hydrogen was used as an electricity source,
the amount of modification required could be significantly less.
The timing of taking large‐scale clean H2 would be getting the cost base H2 from renewable source
closer to the current production cost, whether by Steam Methane Reforming (SMR) or electrolysis
from water. There are several sites that could be used to demonstrate the use of clean hydrogen.
However, a demonstration plant that integrates green hydrogen from an electrolyser, into a refinery
would have minimal material impact on the amount of hydrogen consumed. The largest electrolyser
being installed globally, at Rhineland, has a capacity of 10MW, which equates to approximately
1,300t/year of green hydrogen. This is approximately 0.7% of all hydrogen consumed there. In
Australia, while any reduction could be beneficial, having a secondary, stand‐alone electrolyser
would never be able to replace current SMR processes during an outage because electrolyser sizes
and hence volumes are still too small.
Odorising reagents containing sulphide can also impact the quality of the hydrogen for industrial use
and fuel cells. Sulphide is considered as a fuel cell degradation reagent or catalyst. Therefore,
odorant exemptions for industrial processes could also be considered to resolve these challenges
and protect equipment.
Quote from report 19184‐REP‐001‐rC
“Introduction of H2 has shown some benefits for engines (internal combustion) such as improving
the lean‐burn capability and flame burning velocity of natural gas engines under lean‐burn
conditions, as an increase in flow intensity is introduced in the cylinder which results in improved
engine efficiency but at the expenses of increased engine wear and increased NOx emission.”
At ambient temperatures, oxygen and nitrogen do not react. However, at high temperatures, they
undergo an endothermic reaction producing various species of oxides of nitrogen, some as
intermediate exist in relatively short time spend. NOx can be formed naturally from lightning or
bushfires.
Common NOx control strategies include flame characteristic optimisation (such as lowering the
flame temperature, tunning of oxygen injection) and hardware investment (catalytic low NOx
burner, flue gas recirculation). The former requires fine additional resources for tune and re‐tune on
a regular basis. The latter requires investment in major retrofitting. For Type A appliances, the
potential increases in NOx (when switching to H2 mix to 50% H2 blended) is negligible from
preliminary Australian Gas Association (AGA) testing observations. For Type B, due to the scale and
requirement of the fuel specification, some major upgrade/retrofits would likely be required. Timing
to revisit would be 50% blended H2 in gas network is ready.