Here’s to hydrogen: Australia is missing the potential of solar fuels

It’s time to take solar transport fuels a lot more seriously. National Renewable Energy Lab

Many times in human history governments have tried to write policies based around future technologies and missed identifying the transformational keys. In the 1970s, for example, few if any horizon-scanning policies on communications predicted the internet or mobile phones. Yet scientists are increasingly unified in the need to develop new technologies to address the critical problems now facing us in fields such as energy and climate change.

The Federal Government’s Energy White Paper 2012 aims to chart the nation’s course towards greater energy security while meeting our ethical and legal obligations to mitigate climate change. Clouding the vision, though, is an underlying agenda to profitably privatise electricity services and export coal, natural gas and uranium.

In such a fraught context the tensions of leadership are tersely captured in the report’s conclusion: “Australia’s energy technology and fuel mix should be determined by the market.”

Australia, you’re missing a clean energy source

The document repeatedly makes the case that Australian’s energy sector is transitioning towards clean energy (zero greenhouse gas emissions) sources. But the timetable for this to happen seems seriously out of joint, not only with with the urgency of the climate change problem, but with research in revolutionary areas of clean energy technology.

The report plans for clean energy technologies providing around 40% of Australia’s electricity generation by 2035 and up to 85% by 2050. Large scale solar would contribute 16%, wind energy and household PV 13% each, and hydroelectricity and bioelectricity 5%.

When the report plans for a transformation in transportation fuels by 2050, it mentions biodiesel 13%, natural gas 12%, bio-derived jet fuel 8% and synthetic diesels 2%.

More than 60% of our energy needs involve fuel for planes, ships, trucks, heavy equipment and machinery. mojoey/flickr

Yet it does not discuss molecular solar fuels (the storage of solar energy in non-biological chemical bonds such as hydrogen and its molecular complexes for example with CO2).

Hydrogen’s greatest advantage as a fuel may be in the area of transportation. More than 60% of our energy needs, for example, involve fuel for planes, ships, trucks, heavy equipment and machinery. It has been recognised that providing cheap access to large amounts of hydrogen could significantly enhance our prospects of addressing the critical energy and climate change problems of our time: hydrogen has a high energy density, is not a greenhouse gas and when burnt creates fresh water.

How do solar fuels work?

Scientists have been splitting water molecules to create hydrogen gas for decades, but the process has required electricity or (if solar energy was used) needed expensive rare earth metals such as platinum.

Some of the best prospects of using hydrogen as a fuel involve not condensing it as a gas or liquefying it (which are energy expensive) but storing it in metal hydrides. This leads to the prospect that one day buildings will not only be using sunlight to split water as a source of their hydrogen fuel and part of their contribution to our protective atmosphere (along with absorption of carbon dioxide), but storing it in their structure.

Many energy policy makers and funding agencies (including those in Australia) consider that solar energy research and development is all about photo-voltaics (PV); that is, capturing solar photons for transmission to the electricity grid, batteries or thermal storage. Yet cyanobacteria and plants have been storing solar energy in chemical bonds for several billion years and the scientific challenge of improving upon that whole process is perhaps the most important of our time.

Anhydrous ammonia is another potential solar fuel (derived from atmospheric nitrogen). Mostly used as a fertiliser, ammonia is easy to transport and store and can be burned in an internal combustion engine with few modifications and no greenhouse gas emissions. Yet the chemistry challenges in building such a wholly integrated artificial photosynthetic system are complex and expensive to address.

They’re on to it overseas

The US Department of Energy is increasing funding for fuel cells and “hydrogen vehicle systems”. The US National Hydrogen Association and US Fuel Cell Council (USFCC) have set a goal of getting the full $132m additional funding.

The US has seen the potential of hydrogen. waltarrrr/flickr

In the US, a cluster of hydrogen filling stations operates in New York State (including one at JFK Airport operated by Shell, the US Department of Energy and General Motors), making driving between them feasible.

Europe has been supportive of efforts to extend solar hydrogen fuel research and deployment. The European Fuel Cell and Hydrogen Joint Undertaking (FCH JTI) has €1 billion funding available from the European Commission, to spend on transport and refuelling infrastructure, stationary power generation and combined heat and power; portable applications or small utility vehicles); hydrogen production and distribution; training regulators and developing a lifecycle assessment framework.

Fifty-four universities and research institutes form a related research grouping called N.ERGHY. The aim is to put technologies on the market two to five years earlier than they would do without the financial support.

What’s stopping Australia?

It is not only a lack of understanding of the molecular mechanisms involved in artificial photosynthesis’ immensely complex light capture, electron transfer, catalysis and reduction processes that is holding back solar fuels development. Public policy discussion also lacks appreciation of the long-term economic and environmental importance of solar fuels.

Developing clean energy transportation fuels is critical for our economic stability and environmental sustainability. The possibility of electric vehicles with rechargeable batteries is touted (for example in the Energy White Paper) as central to the clean energy transition in the transport sector, but if the electricity is obtained from the grid those vehicles will still contribute to atmospheric greenhouse emissions. There are also major problems with storage and life cycle usage of batteries.

Australia has particular advantages that could easily make us a leader in solar fuels research and development. Our continent has the highest average solar radiation per square metre of any continent. The Clean Energy Finance Corporation is stated to have $10 billion and ARENA $3.2 billion and the Clean Energy Program $1.2 billion to invest in clean energy technologies. Surely a feasible case can be made for such schemes to include funding assisting a broad consortium focused on deployment of a solar fuels prototype?

Large and well funded research projects on molecular solar fuels have now commenced in most developed nations. These are led by organisations such as the US Joint Center on Artificial Photosynthesis (JCAP) involving Caltech and Berkeley, the Solar H2 network in Europe and the Solar Fuels Institute (SOFI) coordinated by Northwestern University in the US.

It is high time Australia set up its own dedicated national solar fuels project.