The Green Goat trainImage source, H2M
Image caption, The Green Goat is getting a green refit

An old diesel freight train is going to get a new lease of life.

The Green Goat locomotive is being converted to run on a mixture of hydrogen and battery power.

Small loads of lumber or animal feed can be transported by the switcher locomotive.

The engine will be running by the end of the year or early next.

"With the successful demonstration of this, we would be looking at larger trains as well," said H2M president and chief executive Grace Quan. Entire fleets would be looked at.

Hydrogen emits water but has no carbon dioxide when burned.

There are hydrogen-powered trains that are currently being rolled out in Germany. It was the technology's debut there in 2018?

There is a hydrogen locomotive in the UK.

Current methods of storing hydrogen in tanks are not safe and are expensive. Scientists have been trying to find a way to store hydrogen in solid form.

Image caption, Grace Quan (front) hopes H2M can convert whole fleets of trains to hydrogen and battery power

H2M has developed a material that stores hydrogen at relatively low pressure compared to other methods.

When the CO2 in a carbonated drink gets released when you open the bottle, it's the same as when hydrogen comes off when you open a valve.

The company has developed a hydrogen-powered three-wheeler tuk tuk as a small scale demonstration.

The tuk tuk could lose up to a week's worth of power depending on the size of the fuel cell.

She says that it has been difficult to get investment funds to develop her technology. Solid state hydrogen storage solutions are at an early stage of development

The biggest challenge they face is to prove that they are worth choosing over batteries for certain applications.

According to Duncan Gregory at the University of Glasgow, those working on hydrogen storage technology want to achieve a density of 5 wt% or greater within the storage medium. He says it is difficult to get to that.

Image source, Deakin Univeristy
Image caption, Srikanth Mateti (left) and Ian Chen are working on a technique to make hydrogen powder

There's a lot of work done. Ian Chen and his colleagues are working on a new method.

Ball milling is a type of grinding process that uses small balls inside a canister. The grinding activity encourages gases to be absorbed by a powder in the canister.

Prof Chen and his colleagues have found a way to store gases.

Prof Chen says that 5 wt% should be possible with this method because it is lightweight and stable.

This process can be used to store hydrocarbons in an academic paper. The details of the experiments in which they were able to store hydrogen and other gases are still being kept under wraps.

Prof Chen is excited by the idea of storing hydrogen in this form, which requires the application of heat to release the gas again. He admits that there is a long way to go between research and commercial success.

The method would need to be shown to be cost-effective at scale. Prof Chen says that they do not claim to have solved all the problems.

Replacing diesel locomotives with hydrogen-powered trains was ruled out by the German state of Baden-Wrttemberg in October.

Overhead electricity lines or battery hybrid trains were found to provide better value for money over a 30 year period.

One of the potential issues with the ball milling process is how long it takes. Prof Chen's small-scale experiments took 20 hours to complete.

Hydrogen stored in a solid state can be used for other purposes. One of the Orkney Islands will be used as a testing ground for hydrogen generation and storage.

The machine-learning system will be able to determine when to use the electricity from the wind turbine to power the electrolysis process.

Enass Abo-Hamed is the chief executive and co- founder of H2GO Power. You could have a week full of wind and then a week without any.

In this case, the system will determine when the hydrogen should be released or stored. The stored energy could be used during a wind shortage.

Image caption, This test site in Orkney uses electricity from wind turbines to make hydrogen powder

The lack of wind has pushed up UK energy prices.

It is possible that hydrogen could be used to power up to 70 homes if the system on Orkney is connected to the local grid during the trial. It could be converted into a gas state in the future and used for domestic heating.

Prof Gregory believes that hydrogen has the potential to be a cleaner boiler fuel than natural gas.

Hydrogen's potential as a fuel has been questioned in recent studies.

If someone can crack the hydrogen storage problem, that could change how we power the world's vehicles.

He thinks batteries could be replaced by hydrogen in 20 years.

  • Hydrogen vehicles
  • Renewable energy