EXCURSION TO FRAUNHOFER CSP: Silicon Solar Cells

Köthen, 3.4.2017

We started our visit at the Hochschule Anhalt with a guided tour through the labs. Afterwards we heard a talk from Prof. Griehl about her research, she is one of the leading algae researchers. At the end we could see the photobioreactor system, that Prof. Griehl developed, following the principle ‘fir-tree’ by the Phd student Christian Kleiner.

Part 1: visiting the lab
A big range of algae are collected in shaking flasks and petri dishes. We see various kinds of bioreactors for the first investigations on the ideal cultivation of algae – to find out how much light and which nutrients are required for the perfect growing conditions. The college closely works together with the industry, since the economic efficiency is an important factor. However, a lot of the research pursued it is still basic research.

Part 2: talk of Prof. Griehl
While eating tasty algae cookies, Prof. Griehl gave us a fundamental insight in algae research by showing us different algae, explaining their functionality and cell construction and also provided us with an insight in their research on algae cultivation for an industrial use.
Even though algae naturally always live with other species and also other organisms, for the work of a biologist it is important to have single (not mixed) cultures to understand them and use them. However, it can take three months to retrieve a single culture out of a mixed one.
Prof. Griehl also showed us various existing alga products. Even though there are numerous kinds of algae only six are approved for use as food (supplement) such as chlorella and spirulina.
We also learned that some green algae contain carotenoids and astaxantin, which are responsible for the different colouring. The algae protect themselves at stress e.g. against too much light with the coloured pigments. This is why there are also red and yellow green algae.

Part 3: visit of the pilot plant of a photo bioreactor after the principle of a ‘Tannenbaum (fir-tree)’ with Christian Kleiner
This photo bioreactor allows an ideal cultivation of algae in a tube system in sunlight. Due to its tree like shape all algae get full light in the morning and afternoon, whereas at lunch time, when the sun is too intense, this geometry provides some shade making use of the sun shining almost vertically.
A special tubing system was also developed: Ideally tempered water is pumped through the tube in a separate channel and keeps the algae at the right temperature, which allows a cultivation outside a greenhouse.
The pilot plant automatically controls the CO2 supply, the filtration of the algae from water as well as the extraction of oil from the algae.