Turning Hydrogen Production Green with Microalgae

by Laura Thomson interview with Akshat Tanksale (AZO CleanTech) Associate Professor Akshat Tanksale at Monash University speaks to AZoCleantech about his research on how microalgae could have significant benefits when applied to the hydrogen production industry.

What makes microalgae a suitable resource that could revolutionize hydrogen production?
Unlike agriculture or forestry-based biomass, microalgae is more suitable for industrial-scale production for energy generation. It is easier to convert into hydrogen since it is made of a simpler cellular structure.

The current best-practice for hydrogen production is steam reforming of methane. What techniques have you used in your research and how do they compare to steam reforming?
We use a method that is similar to steam reforming. In our method, the microalgae first goes through fast pyrolysis (thermal decomposition) to produce volatile bio-oil, which is immediately converted into hydrogen by steam reforming. There are dozens of chemical reactions in our process compared to only a couple of reactions in the steam reforming of methane. The beauty of our method is that all the reactions take place in a matter of microseconds. This is achieved by a novel catalyst that was designed specifically for microalgae conversion.

Using microalgae to produce hydrogen emits 36% less greenhouse gas emissions than current methods, with the possibility of this figure increasing to 87% with the incorporation of additional renewable energy processes.

Our techno-economic model suggests that at $10/kg compressed hydrogen (at 700 bar pressure), the payback period for hydrogen production at a scale of ~30 tons per day is only 3.78 years with a 22% return on investment. Therefore, it is viable for a large-scale operation.

Hydrogen production from microalgae using Reactive Flash Volatilisation produces 36% less greenhouse gas emissions compared to the steam reforming of methane gas – the current best practice for hydrogen production. With additional renewable energy processes such as hydroelectricity being integrated into our hydrogen production process, carbon emissions could drop by as much as 87%.

Hydrogen production via renewable resources is essential to solve the energy crisis and bring down the global emissions from fossil fuels. Currently, a vast majority of hydrogen comes from fossil fuels, which causes carbon dioxide emissions, leading to climate change. Hydrogen production via microalgae is potentially carbon neutral.

One of the challenges that must be overcome is the scaleup and commercialization of microalgae production processes. Photobioreactor advancements are being made to produce microalgae in high concentration and low footprint. However, they are not yet at a stage where they can be applied to energy applications due to the sheer size of energy demand.

The next steps in the project are to test this process at a pilot scale and conduct long-term studies on the yield of hydrogen from microalgae and link it with renewable electricity to power the compression of hydrogen for storage. READ MORE