Green hydrogen could decarbonize entire industries in NZ—but there’s a long way to go

Hydrogen has been known as the “Swiss army knife” of decarbonization as a result of it could possibly do many issues. However not all of them make sense.

Immediately, the world makes use of about 100 megatons of hydrogen per yr (MT/y), however that is produced virtually totally from fossil fuels. To make use of hydrogen for decarbonization, we should shift to emissions-free types.

International forecasts for inexperienced hydrogen produced from renewable sources fluctuate broadly, starting from at this time’s demand (100 MT/y) to an optimistic 700 MT/y by 2050. Bloomberg’s recent 2050 forecast suggests a downward development. Even so, shifting at this time’s demand to inexperienced hydrogen poses important challenges.

In our analysis, we use the “clean hydrogen ladder” to type and quantify totally different makes use of of inexperienced hydrogen.

Hydrogen demand in New Zealand

Our research reveals New Zealand’s whole demand for inexperienced hydrogen can be round 2.8 Mt/y if all technically possible functions switched to hydrogen. If we prioritize makes use of the place inexperienced hydrogen is the one decarbonization possibility, demand can be as much as 1 MT/y.

Fertilizer and methanol are on the high of the record. They’re thought-about “unavoidable” as a result of there aren’t any different alternate options for decarbonization. Collectively, they might require about 0.2 MT/y.

Subsequent on the record are issues like delivery and jet gas (by hydrogen-based artificial fuels), steel production and long-term grid storage. These may add one other 0.7 MT/y.

On the different finish of the ladder is the place hydrogen is uncompetitive as a result of there are higher alternate options, like battery electrical vehicles or warmth pumps.

To supply 1 MT/y of inexperienced hydrogen, New Zealand would wish to triple the put in capability of renewable energy crops and build out a massive 10 GW of electrolysers (units that makes use of electrical energy to acquire hydrogen from water).

Lengthy-term hydrogen storage

A strategic use of hydrogen is long-duration storage to maneuver low cost photo voltaic power from summer time to winter, past what hydropower reservoirs can steadiness.

Hydrogen will be saved in complicated chemical buildings, BBQ-sized tanks and gasoline tankers (ships). However very giant quantities of hydrogen will should be held underground, with depleted pure gasoline reservoirs providing probably the most promising websites.

There are a number of challenges to be addressed to switch hydrogen into storage at three or extra kilometers underground—and get it again up once more. First, as a molecule, hydrogen will not be properly behaved. It tends to stream by supplies that may comprise it. This implies we have to use specialised (costly) supplies together with cautious leak detection.

Second, current discoveries of thriving microbial communities in New Zealand’s gasoline fields elevate the prospect of renewable gases turning into a meals supply for microbes quite than an power supply.

Ironmaking

One other urgent software for hydrogen is to decarbonize metal manufacturing (which accounts for 8% of global greenhouse gas emissions).

Immediately, coal is used to strip oxygen from iron ore and supply combustion warmth. Renewable electrical energy may provide warmth and hydrogen to interchange coal. The so-called hydrogen-based direct decreased iron (H2-DRI) course of is possible at scale, as demonstrated by Midrex, HYBRIT and POSCO.

In collaboration with Victoria College of Wellington, in a undertaking on zero-carbon production of metalswe discovered that electrical energy costs beneath NZ$0.13/kWh are obligatory for hydrogen metal making to compete with the standard coal-based process. Photo voltaic PV is already considerably below these costs during daytime and shut with battery backup.

Exporting hydrogen

New Zealand’s interim hydrogen roadmap suggests hydrogen exports of about 0.5 MT/y. Assembly home hydrogen demand is difficult sufficient, however export ambitions add one other layer of complexity.

Hydrogen is tough to move as a result of it’s a very gentle gasoline that takes up numerous area. However it may be densified. Earlier analysis explored the feasibility of hydrogen exports from New Zealand cryogenic liquefaction, ammonia conversion and toluene hydrogenation.

Liquid hydrogen, whereas decrease in value, boils at minus 253°C and requires specialised insulated transport vessels, with notable losses anticipated from boil-off. On high of that, the infrastructure to ship giant portions of liquid hydrogen across the globe doesn’t at the moment exist.

Ammonia, transported at minus 33°C, suffers much less from boil-off and is extra sensible. Subsequent-generation catalysts akin to these from liquid may make ammonia much more favorable. The third possibility, toluene-MCH, entails increased prices, however is being tested at a commercial scale in Japan.

Current analysis highlights a fourth different, e-methanol produced from green hydrogen. E-methanol is promising due to its modularity and since we already know transport and retailer it. Nevertheless, different researchers see e-methane as more promising because it may leverage current port and pipeline infrastructures.

The price of hydrogen

By way of prices, hydrogen has a protracted solution to go.

To scale back prices, electrolyzers will be scaled up, although this will increase tools bills and creates a trade-off between capital and operating costs. Moreover, electrolyzers depend on costly and scarce supplies like platinum and iridium. Our analysis focuses on creating low-cost electrolyzers by using earth-abundant supplies.

Apparently, different alternate options for emissions-free hydrogen are rising. So-called “gold” and “orange” hydrogen (from pure accumulation or enhancement of olivine to serpentine, respectively) are good examples. Tantalizingly, New Zealand’s distinctive geology gives the potential of each discovering “gold” and inducing “orange” hydrogen.

In the end, the success of hydrogen will rely on competitiveness in opposition to different options, primarily electrification and biofuels. For functions with no straightforward different, emissions-free hydrogen is a direct possibility.

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