Pursuing Net Zero with Alternative Fuels

Cardiff: It’s a challenge always as we tend to speak different languages – sometimes we’re very technical and very specific in our approaches, whereas they are more practical and want to then get their products out. But one of the things that has been really good particularly for this project has been that since the beginning we have kept an open conversation with Flogas, and this has been a relationship that has led to successful outcomes.

Flogas: We saw the commercial opportunity for Amburn to take ammonia and see if you could burn it directly as a fuel, so we reached out to BEIS but then needed to find some very clever people to help us design this. Luckily we stumbled across Cardiff University and Agustin and Syed, so it’s been very good.

Cardiff: We partner with a lot of industry, with all sectors across many areas, and it’s always been very productive. It’s true that sometimes one has to learn to speak to one another but the work becomes more inclusive.

Liquified ammonia is the best solution because at 8 bar it’s liquid at 15 degrees Celsius, so you are actually not pressurising too much and you don’t have to think about temperature in the same way as for hydrogen. With hydrogen you need to have 350 to 800 bar to gasify and to liquify you need -250 degrees Celsius. Ammonia is a solution that can have both these obstacles taken care of and at the same time ammonia has more hydrogen than hydrogen itself. So we’re actually moving more hydrogen by moving liquified ammonia. If you can use ammonia for direct combustion then you’re taking out the problem of cracking, so you’re saving more energy.

In terms of risk of explosion, ammonia is the opposite of hydrogen. Ammonia is very hard to alight, so this is a good side and bad side of ammonia. To mitigate this problem we can mix it with some hydrogen or ethanol to make it more reactive. Our solution is to have ammonia hydrogen, where we crack some of the ammonia to make some hydrogen, we make a blend out of it and then we burn that. It has similar structure and similar properties as fossil fuel.

In terms of problems, ammonia is toxic, but ammonia has been used in the fertiliser industry for over 200 years. Although it has some health and safety issues it is not like we’re using it for the first time. We’ve been using it, we just have to use some more robust health and safety guidelines on ammonia. As a part of the Amburn project we are doing that, and have hired a third party specialist to look at these health and safety factors of ammonia. So ammonia has more upsides than downsides.

At the moment there is very little green or blue ammonia available on the market, but there are a number of large projects which are building infrastructure or will be building infrastructure in Britain to import ammonia from the US or the Middle East, and the indications that we’ve had are very favourable. The ammonia imported price would be comparable to natural gas price that we saw last winter. That was a little bit higher than normal but if we can get green ammonia at that sort of price level it’s going to be very impressive. That likely will start coming on stream and being imported in 2027/28, so not too far into the distant future.

It comes down to the new technologies that are under development. From our side we tend to work on the thermal part, the final use and the storage and distribution of the chemical. But there are universities and also research groups working already on different approaches to produce ammonia sustainably. The first is using electrolysers to split water and produce hydrogen, using renewable energy to do so, and this can produce green ammonia. The problem is that electrolysers are still very expensive and the electricity requirements are very high. These universities and institutions are trying to jump into what we call generation 3 of ammonia production, looking at the production of ammonia using only water and air, using a catalyst or a fuel cell that will allow us to produce the ammonia directly. So anyone that has access to renewable energy, air and water will be able to produce ammonia. On those lines, right now the amount of ammonia produced that way is very little and still in its infancy, but the whole industry is looking at that and the potential for this as the holy grail of energy production.

The potential is quite high, and this is one of the open points that we’ve been trying to expand as well. One of the programmes that is going on is between NASA and Boeing to use ammonia as a hydrogen carrier, and they are looking into the use of direct ammonia. At the end of the 1970s and early 1980s there was an interesting programme to use oxygen as a method of boosting ammonia flames and the reactions they were using for aviation were fantastic. There is a lot of potential in this area and further in the future.

QUESTION (not covered during live Q&A)

ANSWER

Do you think zero carbon fuels will just buy “us” time to progress renewable energy storage (and production issues) or is it a long term solution?

We believe it’s a long term solution. Transport, off-the-grid locations, island-based systems, etc. are unlikely to generate enough energy to operate, hence requiring a fuel.

Yes. Through the NZ innovation institute we’re bringing collaboration from all the schools to tackle climate change and energy supply. We’ve got ongoing works with Social Sciences, Chemistry, Engin, Biology, Architecture, etc. Otherwise, the solution is not complete.

Absolutely! A few years ago, I presented the potential use of ammonia as a rocket fuel for space exploration, with the moons of Saturn being potential candidates for refineries and fulling centres. Still far from where we are, but potential to support civilization to get out of the Solar System.

Currently, we’re leading the Scientific Committee of the Symposium on Ammonia Energy, a 84-members internationally recognised group working on ammonia. Our aim is to convert the symposium in a new Ammonia Energy Society. To back this up, we’ve got relations with +20 large industries, whilst economies such as Japan and China have already industrial operational systems working on ammonia. With a total of £12M that we’re managing in 7 NH3-based projects, we believe that what was the plan is now a tangible reality for plans to create the European Hub on ammonia research.

Yes, hydrazine was actually highly employed in aerospace – still is, as a backup fuel. However, it’s toxic nature and high reactivity have made the chemical a last resource option. Besides, hydrazine is obtained from ammonia. For more info, please check one of our publications on the subject – https://pubs.acs.org/doi/full/10.1021/acs.chemrev.9b00538

Toxic nature of the chemical at low concentrations and low reactivity. Other challenges such as corrosion can play an important part with the wrong materials. However, the research currently using ammonia is based on solving these 3 problems (and that includes public perception).

Yes – NH3 is a well-known de-noxing agent. As you burn rich (excess of fuel), some of the ammonia is unburned due to the lack of oxygen. That same unburned ammonia is then recombined with the NOx produce at the flame front, reducing both at the same time and obtaining N2 and H2O.

Yes – Ammonia is a global commodity used for fertilizing applications. It’s estimated that 1/3 of the global population would not exist without ammonia. It’s also used in cleaning products, textile production, chemical processes, etc. Hence, it’s in every country. Regarding Biases, ammonia is not the final bullet to solve all our energy problems. Hence, there are many obstacles that need to be solved before we can fully use it as a fuel. It is along those challenges that we have based our research, creating a new area that has been explored just over the last decade.

I believe that carbon offsetting is not effective unless CCS is involved in the process. Having said that, the ammonia we’ve been talking about is either blue or green. The former fits the description and can allow for CCS system installations to sequestrate CO2, hence avoiding the gas to impact climate change. However, the final aim is to reach green ammonia production using renewable energies that are a Surplus to the energy requirements from the grid. If that happens, we’ll have energy storage that will support alternative electrical power, ensuring clean sources with reliable storage.