CyanoCapture: using algae to fight climate change
March 1, 2023

What is carbon capture? Why is it important?

Carbon capture is a way of reducing carbon dioxide emissions from industrial processes. At CyanoCapture we are harnessing biology to do this. Cyanobacteria are microalgae that naturally capture carbon during photosynthesis. Carbon capture is important for preventing carbon dioxide from entering the atmosphere which would otherwise contribute to climate change.

What are some challenges facing carbon capture technologies today and how does CyanoCapture tackle them?

The cost of scaling up is the major factor facing carbon capture technologies today. Existing closed photobioreactor (PBR) designs such as tubular glass reactors are expensive to set up and maintain at scale whilst open pond systems are less expensive but produce lower productivity and are more susceptible to contamination. At CyanoCapture we are developing our own novel PBR design that combines the benefits of existing systems and are constructed from affordable materials and have low operating costs such as using natural sunlight rather than artificial light. Additionally, we are using wastewater to grow our cyanobacteria. Wastewater can be rich in nutrients such as nitrates and phosphates that cyanobacteria require to grow. By utilising wastewater, we are sustainably obtaining nutrients with the added benefit of preventing the ecological damage associated with wastewater.

What is Synechococcus and why is it so useful?

Synechococcus is a genus of cyanobacteria, with species that can be found in a variety of seawater and freshwater environments. We are using a strain of Synechococcus that has increased productivity compared to other commonly used strains and it is tolerant to a range of salinities and temperatures. This is important for growth under different environmental conditions. The strain is also able to be genetically modified, therefore one area of our work focuses on using genetic engineering to enhance its carbon capture ability.

How does CyanoCapture plan to scale up its technology?

We are combining innovation in engineering and biology to enable scaling up of our technology. Our engineering team is developing a low cost, low energy PBR design and downstream processing of the cyanobacteria biomass. In addition, our biology team is focusing on genetic engineering of the cyanobacteria to enhance its carbon capture ability and produce by-products that will provide another revenue stream. Also, we are optimising the growth conditions and nutrient utilisation to boost productivity whilst maintaining low operating costs. We are piloting our technology at different emission sites to test a variety of flue gas and wastewater sources and are constantly learning about what improvements we can make.

Why is having a thermodynamically favourable method of CO2 removal important?

CO2 removal needs to be low energy in order for the carbon capture to be true. Otherwise equal or more energy would be required to capture the carbon than that which is already being emitted. Therefore, this is the driving force behind our technology.

What developments are you most excited about in synthetic biology?

Cyanobacteria are incredibly useful in synthetic biology because they can produce useful bioproducts from only CO2 and light. For example, we are particularly interested in recent genetic engineering work that enabled the production of palm oil alternatives and bioplastics. I am also interested in newly developing cyanobacteria CRISPR technologies that allow more precise and rapid genetic engineering. 

Do you have any advice or resources for students interested in bioenergy and carbon capture technologies?

Keep up to date with current developments in your areas of interest and identify ways you think current technologies can be improved. Also, reach out to companies you are interested in and enquire about any internship opportunities. Small companies in particular will be looking for motivated people with fresh ideas.