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The exploitation of microalgae for energy is possible!

Timo Enderle (cofactor – a consulting company focusing on algal biotechnology) believes that the efficient cultivation of microalgae can be further optimised and that the use of microalgae for energy will become possible in the not-too-distant future. Enderle spoke with Martin Follmann (BIOPRO Baden-Württemberg) about the prospects for algal biotechnology.

Mr. Enderle, it seems that we are – once again – going through another period of hype about algal biotechnology. Why do you think this is?

Timo Enderle and Martin Follmann discussing algal biotechnology. Timo Enderle (right) believes that reactor design, cultivation of microalgae and downstream processing have room for optimisation. © BIOPRO / Jonischkeit

I think this is due to several factors: On the one hand, the current hype is due to rising oil prices and the fact that we are aware of the finiteness of oil resources. On the other hand the potential to decrease CO2 emissions is very much a current topic of debate. So naturally we are looking to clean raw materials to replace oil as fuel, but also to replace products in the plastics industry. Algae are seen as clean oil producers, particularly so because the cultivation of algae does not compete with the production of food.

The hype is most obvious in the USA where another issue comes into play, namely the independence from fossil-based energy. Particularly in view of the current political upheavals in the Middle East, the USA is keen  to become independent from the oil-producing countries. It ought to be mentioned that a considerable proportion of the funds set aside for algal biotechnology comes from the American Department of Defence.

I do not feel that there is so much hype in Germany. Here, companies and research institutions deal with this technology in a more factual way. Concepts relating to the use of algae for the production of energy and the type of research that is required to achieve this are also very realistic.

What are the major applications of algae? Can you also tell us what has been established, what can be achieved in the not-too-distant future and what is simply utopian?

"In the USA, huge sums of government funding are available, even for something which is nothing more than an excellent idea...." © BIOPRO / Jonischkeit

Algae are a major food supplement, in particular in Asian countries. They are also used as feedstuff for example in aquacultures to breed fish larvae. These are all small, but nevertheless important markets. Also, the production of high value products such as beta carotene and omega-3 fatty acids for use in the food sector has already become profitable. As I see it, I would not consider any of the topics that are currently being debated to be utopian. I am an optimist myself and in the past developments happened that nobody actually thought were possible – the aerospace industry for one.

However, the different scenarios for the use of algae are all associated with different research and development expenditures and durations.

For me, the use of algae for energy is heading in the right direction, although there is still some work ahead of us. For example, I could cite the use of residual biomass that is being used as feedstuff. It should be taken into account that the large-scale application of algal biomass will only become possible when positive economic and ecological balances are achieved. 

"... and I would very much like us Germans to be more courageous in this respect." © BIOPRO / Jonischkeit

With regard to the use of algae for energy, some people are highly optimistic, whereas others are highly sceptical. Do you think the use of microalgae for energy is at all feasible?

Yes, definitely! Researchers and developers have shown, both in technical and biological terms, that it is possible to efficiently produce energy carriers using microalgae. However, we are still not able to develop a commercial production facility whose energy input is lower than its energy output.

… which is something that is crucial for the use of microalgae for energy production...

Exactly! However, there is still major optimisation potential in reactor design, algae cultivation and the selection of suitable microalgae. Therefore, I assume that a positive energy balance will be achieved.

Which type of energy carriers can be produced?

First of all, there is the algal biomass that can be pressed and burnt. However, this is not really feasible for either economic or energy production reasons. In addition, biomass can be fermented into biogas under aerobic conditions. Although this is quite feasible from the energy point of view, it is not at all profitable since production costs per kg algae are still too high to enable us to “just” produce biogas.

In addition, algal oil has many uses. Some microalgae can produce large amounts of oil. It can be esterified into biodiesel or hydrated into synthetic fuels (e.g. aeroplane fuel). Then there are algae that can produce alkanes and release them into a given medium. These fuels are extremely interesting for the aerospace industry as their energy density makes them suitable for use in aeroplanes.

Algal starch can be fermented into bioethanol. And some algae produce hydrogen under certain conditions; hydrogen is another type of fuel that is regarded as clean.

Which energy carrier has the greatest potential in the near future? Oils? And where do you foresee the greatest difficulties?

That’s a difficult question to answer. I actually believe that the majority and also the most promising approaches are found in the area of hydrated oils. However, the downstream process, i.e. purification and processing – is far from being an insignificant issue, particularly from an economic point of view. One also needs to take into account that the large-scale technical implementation of biotechnological processes is not easy. I am sure the scaling-up process has some challenges in store for us.

However, it’s very safe to say that we are still a long way from the industrial production of hydrogen. We are still at the very early stages of research.

The main requirement is to reduce the costs of production of the final product, and this is true for all the energy carriers we are talking about.

How can this be achieved? Where can costs be reduced? In the field of biology or in the field of process engineering?

What we are trying to do is to produce as much algal biomass on as little as possible space at as low a price as possible at the same time as exploiting the sun as optimally as we can. These are the areas where efficiencies can be made in the field of biology and in the field of process engineering. It is important to select the correct microalgae and find molecular biology methods to manipulate them with a particular goal in mind. We also need to select and develop suitable reactors and cultivation processes. The entire workflow ends with the downstream process, i.e. the separation and drying of the sought-after product, something that can be costly and time-consuming. I believe that all production steps can still be optimised.

Your prognosis: when will the first economically viable facility for using algae for energy start operating?

As I see it, I think the first economically viable facility will be up and running in about five to ten years. However, I also believe that the first facilities will be used for the production of a high value product as well as for the energetic use of the remaining biomass. The combination of energy and high value product production is economically viable, at least to start with.

Algal biotechnology is driven by the growing demand for energy as well as by the efforts to reduce CO2 emissions. The brochures of some energy suppliers sometimes suggest that microalgae are able to remove a significant proportion of carbon dioxide from power station waste gases. Is this feasible?

Microalgae need CO2 to grow; they need around 2 kg CO2 for one kg algal mass. We can make use of this by cultivating algae in power station waste gases. The operator of the power station can then make money as part of emissions trading. However, the savings per t of CO2 are currently still too low, which is why this option is not yet economically viable. However, if the amount saved increases, I believe that emissions trading might make a contribution to co-financing an algal facility.

I see. Are you saying that it is advantageous to cultivate algae in the CO2-enriched waste gases of power stations, in particular when you take into consideration that the atmospheric concentration of CO2 is too low for optimal algal growth? You are also saying that emissions trading can contribute to the financing of algal plants. However, I do not think there is a way to make a coal power station completely CO2-free just by using microalgae. I did some rough calculations and found that in order to fix all CO2 emitted by a medium-sized power station, an area of the size of Stuttgart would need to be used to grow algae, even assuming that there are rather optimistic plans.

Yes you’re right, particularly as true CO2 sequestration would mean that fixed CO2 must never again enter the carbon cycle. And this could only be achieved by using algae as construction material that would at no time be used for the production of energy. Culturing algae at higher CO2 concentrations is cost efficient, for example in the waste gases of a power station. In addition, emissions trading can also help to finance microalgal plants, but we are not going to be able to render a power station completely CO2-free, at least not in the near future. However, I think it is excellent that energy and CO2 problems are driving forward the development of algal biotechnology. And the first fruits can already be harvested in the fields of food supplements, feedstuff additions and high value products.

How is Germany positioned in relation to other countries in the development of algal biotechnology?

Interesting approaches are being pursued in Germany and numerous promising technologies are being developed. However, in contrast to the USA, much less funding is available in Germany to support these developments. In the USA, a lot of venture capital is available for algal biotechnology. The US Department of Defence also injects huge amounts of money into this type of research. I have already mentioned that the USA’s objective is to become independent from energy-producing countries. On the other hand, the issue is also related to the different mentalities of Germans and Americans. Americans are prepared to spend money for excellent ideas whereas the situation is somewhat different in Germany – partly due to lower amounts of available venture capital, but also because of the German research culture. German scientists want to be 100% sure that something works before publishing the results. I think we are more modest. I myself tend to encourage people to publish results if 80% of a solution is available as this enables companies or researchers to find suitable partners for the remaining 20%.

How about Baden-Württemberg? How are we positioned in relation to other German states? Do we have a unique selling point?

Baden-Württemberg is very well positioned, although, unusually, in the case of algal biotechnology, we are not among the top. The eastern German states focus much more on biotechnology, Brandenburg, in particular. However, Baden-Württemberg is home to innovative companies, for example Subitec, breen biotec and others, as well as outstanding research. The group led by Professor Posten at the Karlsruhe Institute of Technology is, for example, setting international standards in the field of photo-biotechnology.

The topic of algal biotechnology is increasingly being seen as a real future technology. And the information portal run by BIOPRO makes an excellent contribution to this development by realistically presenting the technology.

… thank you very much! May I ask you a personal question? Does your company, cofactor, have any plans related to algal biotechnology?

cofactor is a consulting company in the field of biotechnology with a special focus on algal biotechnology – we have outstanding skills in this field. We work mainly as mediators between science and industry and hope to be able to help innovations to successfully enter the market.

Timo Enderle
Gaußstr. 25
D-70193 Stuttgart
Tel.: +49 (0) 711 31 96 615
E-mail: info[at]cofactor.de
Internet: www.cofactor.de

Website address: https://www.biooekonomie-bw.de/en/articles/news/the-exploitation-of-microalgae-for-energy-is-possible