Tag Archives for hydrogen

Morrison government lays down five technologies for its clean energy investment


Michelle Grattan, University of Canberra

The Morrison government will tell its refocused clean energy agencies and the clean energy regulator to give priority to investment in five low emissions technologies and report how they are accelerating them.

The technologies are clean hydrogen, energy storage, low carbon steel and aluminium, carbon capture and storage, and soil carbon.

The government last week announced it would legislate to extend the remit of the Australian Renewable Energy Agency (ARENA) and the Clean Energy Finance Corporation (CEFC) beyond renewables.

On Tuesday it will indicate the “priority low emissions technologies” they, and the Clean Energy Regulator (CER) – which is responsible for administering the government’s emissions reduction fund – should concentrate on.

Energy Minister Angus Taylor, in a Tuesday speech on low emissions technology, will say the government is putting technologies into four categories. Apart from the priority low emissions technologies, the other categories are emerging and enabling technologies, “watching brief” technologies, and mature technologies.

Priority technologies “are those expected to have transformational impacts here and globally and are not yet mature,” Taylor says in his speech, released ahead of delivery.

“They are priorities where government investments can make a difference in reducing costs and improving technology readiness.

“Technologies where we, as a government, will not only prioritise our investments but where we will streamline regulation and legislation to encourage investment.

“Investors will have confidence that identified priority technologies are of long-term strategic importance for the government.”

Emerging and enabling technologies, such as those for energy efficiency and infrastructure for electric and hydrogen vehicle charging/ refuelling, will also be included in the mandate of the government’s investment agencies.

In the “watching brief” category are those that are for the longer run or are longer odds, such as direct air capture and small nuclear modular reactors. (There is a moratorium on nuclear power in Australia at the moment but the government is watching developments in Europe and the United Kingdom.)

Notably, key renewables and key fossil fuels are in the “mature” category, which includes coal, gas, solar and wind.

The government says it will only invest in them where there is market failure or where such investments secure jobs in key industries.

Last week Scott Morrison threatened to build a gas power station in the Hunter region if private investors left a supply gap for when the Liddell coal-fired station closes, while he also indicated renewables could now stand on their own feet.

Taylor will release an overarching technology roadmap, which he says “arms the government with “four levers to enact change”: an investment lever, a legislative lever, a regulator lever, and international co-operation and collaboration.

“The roadmap will guide the deployment of the $18 billion that will be invested, including through the CEFC, ARENA, the Climate Solutions Fund [which will evolve from the Emissions Reduction Fund] and the CER.

“This will turn that into at least $50 billion through the private sector, state governments, research institutions and other publicly funded bodies. That will drive around 130 000 jobs to 2030,” Taylor says.

The legislative level “is about flexibility and accountability.

“We don’t currently have that. Our agencies are restricted by legislation and regulation to invest in the new technologies of 2010 not the emerging technologies of 2020.”

The regulator lever “is about enablement”.

Taylor says the government’s plan is not based on ideology but “balance and outcomes”.

The government is announcing several “stretch goals” (see table for details). Stretch goals are the point at which new technologies become competitive with existing alternatives. The government announced the hydrogen stretch goal earlier in the year.

“Getting these technologies right will strengthen our economy and create jobs,” Taylor says.

“This will significantly reduce global emissions, across sectors that emit 45 billion tonnes annually.

“Australia alone will avoid 250 million tonnes of emissions by 2040.”

He says “Australia can’t and shouldn’t damage its economy to reduce emissions”.

The Conversation

Michelle Grattan, Professorial Fellow, University of Canberra

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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Time to get real: amid the hydrogen hype, let’s talk about what will actually work



Shutterstock

Jake Whitehead, The University of Queensland; Peter Newman, Curtin University, and Thomas Bräunl, University of Western Australia

For 50 years hydrogen has been championed as a clean-burning gas that could help reduce greenhouse gas emissions. The idea of a “hydrogen economy” is now enjoying a new wave of enthusiasm — but it is not a silver bullet.

Amid the current hydrogen hype, there is little discussion about when the technology can realistically become commercially viable, or the best ways it can be used to cut emissions.

Australia must use hydrogen intelligently and strategically. Otherwise, we risk supporting a comparatively energy-intensive technology in uses that don’t make sense. This would waste valuable renewable energy resources and land space, increase costs for Australians and slow emissions reduction.

Here’s where we can focus hydrogen investment to get the best bang for our buck.

An industrial skyline
A poorly targeted hydrogen strategy will slow emissions reduction.
AP

Hydrogen sucks up energy and space

Hydrogen is the most abundant element in the universe, but rarely is it freely available. It must be unlocked from water (H2O) or fossil fuels such as methane (CH4), then compressed for transport and use. These steps waste a lot of energy.

To be transported, for example, hydrogen must be kept under high pressure or extremely low temperature. And in terms of energy storage, even heating up stones is more efficient.

Australia could become a renewable energy superpower in the future. But there are serious medium-term challenges, including constraints in the infrastructure that transmits energy.

The world must reach net-zero emissions within 30 years to avert the worst climate change. That means using renewable energy as efficiently as possible to maximise emissions reductions and minimise the land space required. So we must be strategic in how and where we use hydrogen.

Hydrogen pathways.
Staffell et al 2018. The role of hydrogen and fuel cells in the global energy system.

Use hydrogen in places electricity won’t go

In most applications, renewables-based electrification has emerged as the most energy efficient, and cost-effective way to strip emissions from the economy.

Yet there are some industries where electrification will remain challenging. It’s here renewable hydrogen — produced from wind and solar energy — will be most important. These industries include steel, cement, aluminium, shipping and aviation.

A renewable hydrogen export market may also emerge in the long-term.

Renewable hydrogen will also be important to replace existing hydrogen produced by fossil fuels. But this alone will require a significant increase in electricity generation, to reach net zero emissions by 2050. This is a major challenge.

Wind turbines on a hill
Australia’s renewable energy capacity would need to increase substantially to produce green hydrogen.
Mick Tsikas/AAP

What about cars and trucks?

Road transport is one area where we believe hydrogen will not play a major role. In fact, Telsa founder Elon Musk has gone as far as to call hydrogen fuel-cell vehicles “mind-bogglingly stupid”.

Hydrogen vehicles will always consume two to four times more energy than battery electric vehicles. This is simply due to the laws of physics, and cannot be resolved by technological improvements.

In the case of hydrogen-powered vehicles, this will mean higher costs for consumers compared to battery-electric vehicles. It also means far more space for solar panels or wind turbines is needed to generate renewable energy.

What’s more, electric vehicles already have longer driving range and continuously expanding charging infrastructure, including ultra-fast chargers.

Comparing the amount of electricity that is lost for hydrogen cars versus electric cars.
Volkswagen AG



Read more:
For hydrogen to be truly ‘clean’ it must be made with renewables, not coal

Most global car makers have recognised the lack of advantage for hydrogen cars and instead invested about US$300 billion in the development and manufacturing of electric cars. Toyota and Hyundai — the last main proponents of hydrogen cars — are also ramping up efforts on electric cars.

As for trucks, the US Department of Energy does not expect hydrogen semi-trailers to be competitive with diesel until around 2050, mainly due to the high cost and low durability of hydrogen fuel cells.

While hydrogen trucks may have a role to play in 20 to 30 years, this will be too late to help reach a 2050 net-zero target. As such, we must explore energy-efficient options already widely deployed overseas, including electric trucks, electrified roads and electrified trailers.

A hydrogen vehicle at a refuelling station
Hydrogen vehicles are less energy-efficient than electric vehicles.
Kydpl Kyodo/AP

A truly strategic plan

If Australia is serious about climate action, we must focus efforts on where renewable hydrogen can deliver the greatest environmental and economic benefits: regional ports.

Hydrogen derived from fossil fuels is currently used to make products such as fertiliser and methanol. Supporting the transition to renewable hydrogen for these uses will be an important first step to scale up the industry.

If produced at regional shipping ports close to aluminium, steel or cement plants, this will provide further opportunities to expand renewable hydrogen use to minerals processing, while creating new jobs.



Read more:
Don’t rush into a hydrogen economy until we know all the risks to our climate

As hydrogen production scales up and costs fall, excess hydrogen would be available at ports for fuelling ships — either directly or through a hydrogen derivative like ammonia. Hydrogen gas could also be used to make carbon-neutral synthetic fuel for planes.

If an international export market emerged in the future, this strategy would also mean renewable hydrogen would be available at ports to directly ship overseas.

Finally, if the development of hydrogen truck technology accelerates before 2050, renewable hydrogen would be available to power the significant number of semi-trailers that travel to and from shipping ports.

Shipping containers and cranes at a port.
A strategic hydrogen plan would link hydrogen production with Australia’s ports.
Daean Lewins/AAP

Let’s get real

Renewable hydrogen is a scarce and valuable resource, and should be directed towards sectors most difficult to decarbonise.

Delaying the electrification of road transport and energy on the promise of hydrogen will ultimately only benefit the fossil fuel industry.



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Creative destruction: the COVID-19 economic crisis is accelerating the demise of fossil fuels


The Conversation

Jake Whitehead, Advance Queensland Industry Research Fellow & Tritum E-Mobility Fellow, The University of Queensland; Peter Newman, Professor of Sustainability, Curtin University, and Thomas Bräunl, Professor of Robotics; Director, WA Electric Vehicle Trial, University of Western Australia

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Enough ambition (and hydrogen) could get Australia to 200% renewable energy



Hydrogen infrastructure in the right places is key to a cleaner, cheaper energy future.
ARENA

Scott Hamilton, University of Melbourne; Changlong Wang, University of Melbourne; Falko Ueckerdt, Potsdam Institute for Climate Impact Research, and Roger Dargaville, Monash University

The possibilities presented by hydrogen are the subject of excited discussion across the world – and across Australia’s political divide, notoriously at war over energy policy.



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Hydrogen fuels rockets, but what about power for daily life? We’re getting closer

On Friday Australia’s chief scientist Alan Finkel will present a national strategy on hydrogen to state, territory and federal energy ministers. Finkel is expected to outline a plan that prioritises hydrogen exports as a profitable way to reduce emissions.

It is to be hoped the strategy is aggressive, rather than timid. Ambition is key in lowering the cost of energy. Australia would do better aiming for 200% renewable energy or more.

It’s likely the national strategy will feature demonstration projects to test the feasibility of new technology, reduce costs, and find ways to share the risk of infrastructure investment between government and industry.

There are still a number of barriers. Existing gas pipelines could be used to transport hydrogen to end-users but current laws are prohibitive, mechanisms like “certificates of origin” are required, and there are still key technology issues, particularly the cost of electrolysis.

These issues raise questions of what a major hydrogen economy really looks like. It may prompt suspicions this is just the a latest energy pipe dream. But our research at the Australian-German Energy Transition Hub argues that an ambitious approach is better than a cautious one.

Aggressively pursing hydrogen exports will reduce costs of domestic energy supply and provide a basis for new export industries, such as greens steel, in a carbon-constrained world.



Read more:
Making Australia a renewable energy exporting superpower

Optimal systems cost less

We used optimisation modelling to examine how a major hydrogen industry might roll out in Australia. We wanted to identify where major plants for electrolysis could be built, asked whether the existing national electricity market should supply the power, and looked at the effect on the cost of the system and, ultimately, energy affordability.

Australian Hydrogen export locations.

Our results show the locations for future hydrogen infrastructure investment will be mainly determined by their capital costs, the share of wind and solar generation and the capacity of electrolysers to responsively provide energy to the system, and the magnitude of hydrogen production.



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How hydrogen power can help us cut emissions, boost exports, and even drive further between refills

We also identified potential demonstration projects across Australia, such as:

  • large-scale production of liquid hydrogen and export from the Pilbara in Western Australia
  • hydrogen to support steel manufacturing in South Australia
  • injecting hydrogen into the gas networks in Victoria and support industry and electricity generation
  • hydrogen to supply transport fuel for major users such as trucks, buses and ferries in New South Wales, and
  • hydrogen to produce ammonia at an existing plant in Queensland.

An export-oriented economy

If we assume electrolysers remain expensive, around A$1,800 per kilowatt, and need to run at close to full-load capacity all the time, the result is large hydrogen exporting hubs across the country, built near high quality solar and wind power resources. Ideal locations tend to be remote from the national energy grid, such as in Western Australia and Northern Territory, or at relatively small-scale in South Australia or Tasmania.

There is much debate around the current cost of electrolysis, but consensus holds that economies of scale will substantially reduce these costs – by as much as an order of magnitude. This is akin to the cost reductions we have seen in solar power and batteries.

200 per cent renewables scenario

This infrastructure requires some major investment. However, our modelling shows that if Australia produces 200% of our energy needs by 2050, exporting the surplus, we see major drops in system costs and lower costs of energy for all Australia. If Australia can produce 400 Terrawatt-hours of hydrogen energy for export, modelling results show the average energy cost could be reduced by more than 30%.

Hydrogen ambition reduces costs of electricity supply.

The driving factor is our level of ambition. The more we lean into decarbonising our economy with green energy, the further the costs fall. The savings from the integrated and optimised use of electrolysers in a renewable-heavy national electricity market outweigh the cost of building large renewable resources in remote locations.

A large hydrogen export industry could generate both substantial export revenue and substantial benefits to the domestic economy.

Hydrogen export economy versus true RE economy

To sum up, the picture above shows two possible hydrogen futures for Australia.

In the first, Australia lacks climate actions and electrolyser costs remain high with limited economies of scale, and we export from key remote hubs such as the Pilbara.



Read more:
We need a national renewables approach, or some states – like NSW – will miss out

In the other, ambition increases and costs drop, and the hydrogen export industry connects to the national grid, providing both renewable exports and benefits to the grid. This also promotes the use of hydrogen in the domestic market. Australia embraces a true renewable economy and a new chapter of major energy exports begins.

Either way, Australia is primed to become a hydrogen exporting superpower.The Conversation

Scott Hamilton, Strategic Advisory Panel Member, Australian-German Energy Transition Hub, University of Melbourne; Changlong Wang, Researcher, The Energy Transition Hub, University of Melbourne; Falko Ueckerdt, , Potsdam Institute for Climate Impact Research, and Roger Dargaville, Senior lecturer, Monash University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Why battery-powered vehicles stack up better than hydrogen



File 20181114 194500 iw2c1a.jpg?ixlib=rb 1.1
A battery electric vehicle in The University of Queensland’s vehicle fleet.
CC BY-ND

Jake Whitehead, The University of Queensland; Robin Smit, The University of Queensland, and Simon Washington, The University of Queensland

Low energy efficiency is already a major problem for petrol and diesel vehicles. Typically, only 20% of the overall well-to-wheel energy is actually used to power these vehicles. The other 80% is lost through oil extraction, refinement, transport, evaporation, and engine heat. This low energy efficiency is the primary reason why fossil fuel vehicles are emissions-intensive, and relatively expensive to run.

With this in mind, we set out to understand the energy efficiency of electric and hydrogen vehicles as part of a recent paper published in the Air Quality and Climate Change Journal.

Electric vehicles stack up best

Based on a wide scan of studies globally, we found that battery electric vehicles have significantly lower energy losses compared to other vehicle technologies. Interestingly, however, the well-to-wheel losses of hydrogen fuel cell vehicles were found to be almost as high as fossil fuel vehicles.

Average well-to-wheel energy losses from different vehicle drivetrain technologies, showing typical values and ranges. Note: these figures account for production, transport and propulsion, but do not capture manufacturing energy requirements, which are currently marginally higher for electric and hydrogen fuel cell vehicles compared to fossil fuel vehicles.

At first, this significant efficiency difference may seem surprising, given the recent attention on using hydrogen for transport.



Read more:
How hydrogen power can help us cut emissions, boost exports, and even drive further between refills

While most hydrogen today (and for the foreseeable future) is produced from fossil fuels, a zero-emission pathway is possible if renewable energy is used to:

Herein lies one of the significant challenges in harnessing hydrogen for transport: there are many more steps in the energy life cycle process, compared with the simpler, direct use of electricity in battery electric vehicles.

Each step in the process incurs an energy penalty, and therefore an efficiency loss. The sum of these losses ultimately explains why hydrogen fuel cell vehicles, on average, require three to four times more energy than battery electric vehicles, per kilometre travelled.

Electricity grid impacts

The future significance of low energy efficiency is made clearer upon examination of the potential electricity grid impacts. If Australia’s existing 14 million light vehicles were electric, they would need about 37 terawatt-hours (TWh) of electricity per year — a 15% increase in national electricity generation (roughly equivalent to Australia’s existing annual renewable generation).

But if this same fleet was converted to run on hydrogen, it would need more than four times the electricity: roughly 157 TWh a year. This would entail a 63% increase in national electricity generation.

A recent Infrastructure Victoria report reached a similar conclusion. It calculated that a full transition to hydrogen in 2046 – for both light and heavy vehicles – would require 64 TWh of electricity, the equivalent of a 147% increase in Victoria’s annual electricity consumption. Battery electric vehicles, meanwhile, would require roughly one third the amount (22 TWh).



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How electric cars can help save the grid

Some may argue that energy efficiency will no longer be important in the future given some forecasts suggest Australia could reach 100% renewable energy as soon as the 2030s. While the current political climate suggests this will be challenging, even as the transition occurs, there will be competing demands for renewable energy between sectors, stressing the continuing importance of energy efficiency.



Read more:
At its current rate, Australia is on track for 50% renewable electricity in 2025

It should also be recognised that higher energy requirements translate to higher energy prices. Even if hydrogen reached price parity with petrol or diesel in the future, electric vehicles would remain 70-90% cheaper to run, because of their higher energy efficiency. This would save the average Australian household more than A$2,000 per year.

Pragmatic plan for the future

Despite the clear energy efficiency advantages of electric vehicles over hydrogen vehicles, the truth is there is no silver bullet. Both technologies face differing challenges in terms of infrastructure, consumer acceptance, grid impacts, technology maturity and reliability, and driving range (the volume needed for sufficient hydrogen compared with the battery energy density for electric vehicles).

Battery electric vehicles are not yet a suitable replacement for every vehicle on our roads. But based on the technology available today, it is clear that a significant proportion of the current fleet could transition to be battery electric, including many cars, buses, and short-haul trucks.

Such a transition represents a sensible, robust and cost-efficient approach for delivering the significant transport emission reductions required within the short time frames outlined by the Intergovernmental Panel on Climate Change’s recent report on restraining global warming to 1.5℃, while also reducing transport costs.

Together with other energy-efficient technologies, such as the direct export of renewable electricity overseas, battery electric vehicles will ensure that the renewable energy we generate over the coming decades is used to reduce the greatest amount of emissions, as quickly as possible.



Read more:
The north’s future is electrifying: powering Asia with renewables

Meanwhile, research should continue into energy efficient options for long-distance trucks, shipping and aircraft, as well as the broader role for both hydrogen and electrification in reducing emissions across other sectors of the economy.

With the Federal Senate Select Committee on Electric Vehicles set to deliver its final report on December 4, let’s hope the continuing importance of energy efficiency in transport has not been forgotten.The Conversation

Jake Whitehead, Research Fellow, The University of Queensland; Robin Smit, Adjunct professor, The University of Queensland, and Simon Washington, Professor and Head of School of Civil Engineering, The University of Queensland

This article is republished from The Conversation under a Creative Commons license. Read the original article.

How hydrogen power can help us cut emissions, boost exports, and even drive further between refills



File 20180823 149484 hfrzfk.jpg?ixlib=rb 1.1
Could this be the way to fill up in future?
CSIRO, Author provided

Sam Bruce, CSIRO

Hydrogen could become a significant part of Australia’s energy landscape within the coming decade, competing with both natural gas and batteries, according to a new CSIRO roadmap for the industry.

Hydrogen gas is a versatile energy carrier with a wide range of potential uses. However, hydrogen is not freely available in the atmosphere as a gas. It therefore requires an energy input and a series of technologies to produce, store and then use it.

Why would we bother? Because hydrogen has several advantages over other energy carriers, such as batteries. It is a single product that can service multiple markets and, if produced using low- or zero-emissions energy sources, it can help us significantly cut greenhouse emissions.

Potential uses for hydrogen.
CSIRO, Author provided

Compared with batteries, hydrogen can release more energy per unit of mass. This means that in contrast to electric battery-powered cars, it can allow passenger vehicles to cover longer distances without refuelling. Refuelling is quicker too, and is likely to stay that way.

The benefits are potentially even greater for heavy vehicles such as buses and trucks which already carry heavy payloads, and where lengthy battery recharge times can affect business models.



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Could hydrogen fuel cell trucks drive our sustainable transport future?

Hydrogen can also play an important role in energy storage, which will be increasingly necessary both in remote operations such as mine sites, and as part of the electricity grid to help smooth out the contribution of renewables such as wind and solar. This could work by using the excess renewable energy (when generation is high and/or demand is low) to drive hydrogen production via electrolysis of water. The hydrogen can then be stored as compressed gas and put into a fuel cell to generate electricity when needed.

Australia is heavily reliant on imported liquid fuels and does not currently have enough liquid fuel held in reserve. Moving towards hydrogen fuel could potentially alleviate this problem. Hydrogen can also be used to produce industrial chemicals such as ammonia and methanol, and is an important ingredient in petroleum refining.

Further, as hydrogen burns without greenhouse emissions, it is one of the few viable green alternatives to natural gas for generating heat.

Our roadmap predicts that the global market for hydrogen will grow in the coming decades. Among the prospective buyers of Australian hydrogen would be Japan, which is comparatively constrained in its ability to generate energy locally. Australia’s extensive natural resources, namely solar, wind, fossil fuels and available land lend favourably to the establishment of hydrogen export supply chains.

Why embrace hydrogen now?

Given its widespread use and benefit, interest in the “hydrogen economy” has peaked and troughed for the past few decades. Why might it be different this time around? While the main motivation is hydrogen’s ability to deliver low-carbon energy, there are a couple of other factors that distinguish today’s situation from previous years.

Our analysis shows that the hydrogen value chain is now underpinned by a series of mature technologies that are technically ready but not yet commercially viable. This means that the narrative around hydrogen has now shifted from one of technology development to “market activation”.

The solar panel industry provides a recent precedent for this kind of burgeoning energy industry. Large-scale solar farms are now generating attractive returns on investment, without any assistance from government. One of the main factors that enabled solar power to reach this tipping point was the increase in production economies of scale, particularly in China. Notably, China has recently emerged as a proponent for hydrogen, earmarking its use in both transport and distributed electricity generation.

But whereas solar power could feed into a market with ready-made infrastructure (the electricity grid), the case is less straightforward for hydrogen. The technologies to help produce and distribute hydrogen will need to develop in concert with the applications themselves.

A roadmap for hydrogen

In light of this, the primary objective of CSIRO’s National Hydrogen Roadmap is to provide a blueprint for the development of a hydrogen industry in Australia. With several activities already underway, it is designed to help industry, government and researchers decide where exactly to focus their attention and investment.

Our first step was to calculate the price points at which hydrogen can compete commercially with other technologies. We then worked backwards along the value chain to understand the key areas of investment needed for hydrogen to achieve competitiveness in each of the identified potential markets. Following this, we modelled the cumulative impact of the investment priorities that would be feasible in or around 2025.


CSIRO, Author provided

What became evident from the report was that the opportunity for clean hydrogen to compete favourably on a cost basis with existing industrial feedstocks and energy carriers in local applications such as transport and remote area power systems is within reach. On the upstream side, some of the most material drivers of reductions in cost include the availability of cheap low emissions electricity, utilisation and size of the asset.



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Why is hydrogen fuel making a comeback?

The development of an export industry, meanwhile, is a potential game-changer for hydrogen and the broader energy sector. While this industry is not expected to scale up until closer to 2030, this will enable the localisation of supply chains, industrialisation and even automation of technology manufacture that will contribute to significant reductions in asset capital costs. It will also enable the development of fossil-fuel-derived hydrogen with carbon capture and storage, and place downward pressure on renewable energy costs dedicated to large scale hydrogen production via electrolysis.

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The Conversation

In light of global trends in industry, energy and transport, development of a hydrogen industry in Australia represents a real opportunity to create new growth areas in our economy. Blessed with unparalleled resources, a skilled workforce and established manufacturing base, Australia is extremely well placed to capitalise on this opportunity. But it won’t eventuate on its own.

Sam Bruce, Manager, CSIRO Futures, CSIRO

This article was originally published on The Conversation. Read the original article.

Explainer: how do we make hydrogen from coal, and is it really a clean fuel?


Jessica Allen, University of Newcastle

Energy giant AGL this week unveiled plans to produce hydrogen power at its Loy Yang A coal station. But how do we transform coal, which is often thought of as simply made of carbon, into hydrogen – a completely different element?

In fact, coal is not just made of carbon. It also contains other elements, one of which is hydrogen. But to get a lot of hydrogen, the coal needs to be “gasified” rather than burned, creating compounds that can then be reacted with water to make hydrogen. This is where the majority of hydrogen comes from in this case – not from the coal itself.



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Why is hydrogen fuel making a comeback?

What is coal made of?

In simple terms, coal is a mixture of two components: carbon-based matter (the decayed remains of prehistoric vegetation) and mineral matter (which comes from the ground from which the coal is dug). The carbon-based matter is composed of five main elements: carbon, hydrogen, oxygen, nitrogen and sulfur.

You can think of coal’s formation process as a progression from biomass (newly dead plant matter) to charcoal (almost pure carbon). Over time, the oxygen and some hydrogen are gradually removed, leaving more and more carbon behind.

Brown coal thus contains slightly more hydrogen than black coal, although the biggest difference between the two is in their carbon and oxygen contents.

https://datawrapper.dwcdn.net/HUgdy/2/

What is gasification?

We can understand gasification by first understanding combustion. Combustion, or burning, is the complete oxidation of a fuel such as coal, a process that produces heat and carbon dioxide. Carbon dioxide itself cannot be further oxidised, and thus is the non-combustible end product of the burning process.

In gasification, however, the coal is not completely oxidised. Instead, the coal is reacted with a compound called a gasification agent. Gasification is endothermic, which means it doesn’t produce heat. Quite the opposite, in fact – it needs heat input to progress. Because the resulting gas is not fully oxidised, that means it can itself be burned as a fuel.

So how do we make hydrogen?

Now we know the key concepts, let’s start again at the start. To produce hydrogen from coal, the process begins with partial oxidation, which means some air is added to the coal, which generates carbon dioxide gas through traditional combustion. Not enough is added, though, to completely burn the coal – only enough to make some heat for the gasification reaction. The partial oxidation also makes its own gasification agent, carbon dioxide.

Carbon dioxide reacts with the rest of the carbon in the coal to form carbon monoxide (this is the endothermic gasification reaction, which needs heat input). No hydrogen yet.

Carbon monoxide in the gas stream is now further reacted with steam, generating hydrogen and carbon dioxide. Now we are making some hydrogen. The hydrogen can then be run through an on-site fuel cell to generate high-efficiency electricity, although the plan at Loy Yang A is to pressurise the hydrogen and ship it off to Japan for their Olympic showcase.

Making hydrogen from coal.
J. Allen

Brown coals are generally preferred for gasification over black coals for several reasons, which makes the brown coal of Victoria’s Latrobe Valley a good prospect for this process.

The main reason is that, because of the high oxygen content of this type of coal, it is less chemically stable and therefore easier to break apart during the gasification reaction. Plus there is a small boost from the hydrogen that is already present in the coal.

Hydrogen produced in this way is not a zero-emission fuel. Carbon dioxide is emitted through the combustion and thermal decomposition reactions, and is also a product of the reaction between carbon monoxide and water to make hydrogen and carbon dioxide.

So why bother making hydrogen?

When hydrogen is used as a fuel, it releases only water as a byproduct. This makes it a zero-emission clean fuel, at least at the point of use.

Producing hydrogen from coal in a large, central facility means pollution control can be put in place. Particulates, and potentially carbon dioxide, can be removed from the gas stream very efficiently.

This is not possible on a small scale, such as hanging off the back of your car. Road transport currently emits dangerous levels of pollutants in our cities every day.



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Gasification processes that use hydrogen fuel cells on site can substantially increase their efficiency compared with traditional coal-fired power. However, depending on the end-use of the hydrogen, and subsequent transport processes, you might be better off in terms of energy output, or efficiency (and therefore carbon emissions), just straight-up burning the coal to make electricity.

But by using gasification of coal to make hydrogen, we can start building much-needed infrastructure and developing consumer markets (that is, hydrogen fuel cell vehicles) for a truly clean future fuel.

The ConversationI predict that hydrogen power will be zero-emission one day. It can be made in a variety of ways through pure water splitting (including electrolysis, or through solar thermochemical and photoelectrochemical technologies, to name a few). It’s not there yet in terms of price or practicality, but it is certainly on its way. Boosting development of the hydrogen economy through production from coal in the meantime is, in my book, not a terrible idea overall.

Jessica Allen, Researcher and Lecturer in Low and Zero Emission Energy, University of Newcastle

This article was originally published on The Conversation. Read the original article.