How cyanobacteria eat iron

I am looking at an ongoing integration of DNA I gave my cyanobacteria to delete the building blocks of the nanowires

Cyanobacteria (commonly known as blue-green algae) obtain energy from photosynthesis: they use sunlight as energy source to convert CO2 and water to sugar and oxygen. Therefore, they contribute a significant part to global carbon fixation. Just like humans, cyanobacteria require iron to survive. While humans can simply eat e.g. spinach, cyanobacteria need to take up iron via other mechanisms. Iron is an abundant element on land so no problem there. However, iron form insoluble particles (rust) when in contact with oxygen and water. Therefore, in oceans, we can hardly find any soluble, easy-to-take-up iron but instead we find rust particles blown from the land into the sea.

The cyanobacteria living there need to deal with rust as their iron source. But everyone who tries to clean his or her bike chain from rust knows how persistent rust can be and that it does not dissolve without difficulty. Therefore, we think that certain cyanobacteria have developed a trick and our hypothesis is as follows: They produce electrons inside of the cell and conduct those via nanowires (hair-like structures on the outside of the cyanobacteria) to the rust particles thereby making the iron soluble again. Then they can take up the newly formed (now called bioavailable) iron.

We see strains of Synechococcus with a deletion of building blocks of nanowires

There is compelling evidence that our hypothesis is true for non-photosynthetic bacteria. It will be my job to identify the building blocks of the nanowires and to see what happens to ‘my’ cyanobacteria (Synechococcus PCC7002) when I delete these building blocks using molecular techniques. If we understand how the electrons are generated and conducted, we could ultimately use cyanobacteria as an alternative renewable source for electricity. Additionally, since cyanobacteria use CO2, the findings of my project could help to reduce the amount of CO2 in our atmosphere and to fight global warming.


Waste gets new life. ISEE Winter School 2016

In the end of January 2016 students from all around the world gathered at Aalto University in Helsinki. They had one thing in common: A passion for renewable energy!

“Thanks for the experience it was a great trip”, ISEE-student

“It was a great week! Amazing people, great to experience Helsinki and to meet classmates. The programme was really good.”, ISEE-student

Thirty-four students from all around the world came to Aalto University in Helsinki 26th to 28th January 2016. Eager to get to know each other and to learn more about renewables. All of them attend a two-year international Master’s programme in Innovative Sustainable Energy Engineering (hence ISEE) a Nordic Five Tech Program.


The Faculty of Natural Sciences and Technology has a coordinating responsibility for the programme, with Prof. Gabriella Tranell as Head of Program (Dept. of Material Science and Engineering).

Professors from University of Iceland, Chalmers, KTH, DTU and NTNU came to Aalto University to present their field of expertise. Students could learn more about geothermal energy, solar cell systems, wind power systems, bioenergy or energy systems.

Waste-to-energy: Puts unwanted waste to use
A highlight of the program was the excursion to Vantaa Energy. Vantaa Energy is one of Finland’s largest city energy companies. They produce and sell electricity and district heating and offer natural gas to industry. Vantaa is proud of their waste-to-energy plant, completed in 2014, that puts unwanted waste to use.

P4_Vantaa Energy_ISEE_blogginnleg
Students were eager and had many questions, connecting their theory and practice when visiting Vanta Energy.


Fast pyrolysis – conversion of biomass to bio-oil

Students in the bioenergy study-track appreciated the visit to VTT Technical Research Centre of Finland Ltd. One of their services is to convert biomass and waste to liquid fuels. The students could see how solid biomaterials may be converted with high efficiency into liquid biofuels using fast pyrolysis. The aim is to replace fossil fuels.

Students also had the opportunity to visit the Labs at Aalto University.
“The labs had good content, especially the carbon capture and storage! And good coffee! :-)” ISEE-student

Visit to VTT. The students could see how solid biomaterials may be converted with high efficiency into liquid biofuels.

The sauna night
On Tuesday we had a dinner for students and professors, in order to mingle and to get to know each other. Last but not least, students were able to experience some of the national pride Wednesday night. The Sauna night was really popular among the students, and we got a taste of real Finish culture at its best.

About the Program
The ISEE Master’s programme is a joint programme based on the alliance of the six Nordic technical universities: NTNU, the Aalto University in Finland, KTH Royal Institute of Technology in Stockholm, the Chalmers University of Technology in Gothenburg, DTU Technical University of Danmark in Copenhagen, and the University of Iceland in Reykjavík. Each university has a responsibility for one of the programme’s six specializations or study tracks.

In the evaluation 28 of 33 students (84,85 %) evaluate the Winter School 2016 as good or very good, and
90,91 % of all the students evaluate the event as very useful for the ISEE Program.


CO2 capture with less energy consumption

MyPhD_100x30_v2In order to stall the climate changes, more CO2 emitting industries must install technology for carbon capture and storage. To make this type of technology more available, I work on a way to make CO2 capture technology less energy demandig.

Since the start of the industrial revolution, the concentration of CO2 in the atmosphere has dramatically increased due to human activity. As CO2 is largely the reason for global warming, it is causing global temperatures and sea level to raise and it is changing weather patterns and climate. Fortunately, there are several measures we can do to prevent damaging consequences of climate change as they are in fact caused by human activity. One solution is carbon capture and storage (CCS).

Chemical absorption of the CO2
In my PhD I will focus on CO2 capture by means of chemical absorption. It is the most mature technology to capture CO2 and has already reached commercial stage at Boundary Dam in Canada. A chemical absorption process capture CO2 from CO2 emitting industries such as combustion of coal and cement production.

How the absorption process works
The flue gas containing CO2 enters an absorption column and reacts counter current with a solvent. After the solvent has captured CO2 it is led to a desorption column where the CO2 is released and the solvent is returned to the absorption column. Unfortunately, the energy demand related to solvent regeneration is high and more research is needed.
My goal is therefore to identify and characterize a solvent system that enable low energy requirement.

An pilot scale system for C02-removal at NTNU. The flue gas enters an absorption column and reacts counter current with a solvent. After the solvent has captured CO2 it is led to a desorption column where the CO2 is released and the solvent is returned to the absorption column.  Unfortunately, the energy demand related to solvent regeneration is high and more research is needed. Photo: Per Henning / NTNU
A pilot scale system for CO2-removal at NTNU. Absorption column to the left and desorption column to the right. Photo: Per Henning / NTNU

Systematic experimental work
A solvent system that has already shown potential to reduce the energy demand is blended amine systems, which consist of a primary or a secondary amine and a tertiary amine. Through targeted experimental work and systematically vary molecular properties of the amines, we hope to find a solvent that will lead to a real break-through in solvent technology. It can then be more economically feasible to implement a CO2 capture technology.


How many moose and deer can a modern forest hold?


As a part of my doctoral degree, I study the interaction between large herbivores like moose and deer, and the forests they live in.

Moose and deer populations have increased drastically in Norway the last decades resulting in a high browsing pressure that is having an effect on forest tree regeneration.

This affects the functioning of forests in terms of timber production, but may also influence other important aspects such as biodiversity, soil fertility, and carbon storage.

Photo: Per Harald Olsen / NTNU

Inside and outside the fence

To study some of the complicated interactions between large herbivores, vegetation, and climate, I compare field measurements made inside and outside large exclosure fences that have been erected on recent logging sites.

By using long-term ecological data collected in several different forest types with known herbivore densities, we hope to be able to explain the observed differences in forest development.

Moose and deer population sizes
Learning about the effects of large herbivores on the forest vegetation will help us identify appropriate moose and deer population sizes to ensure sustainable management of our natural resources, as well as identifying potential conflict between management goals, such as forestry and biological conservation.

The connection between space and Earth weather

MyPhD_100x30_v2As a part of my doctoral degree I will learn more about what happens 90 kilometers over our heads. What happens up there today will influence the weather and climate here at Earth in the weeks to come.

The atmosphere is really more than just air to breath and rain and snow. It warms us – without it we would be about 30 degrees cooler here, it protects us from incoming meteoroids and builds the scene for the fabulous light-show we call northern lights. Yet, many things “up there” are still a mystery to us.

To learn more about all this, we have to become creative. For us, that means looking with a telescope to the darkest spots of the night sky, to listen to burning meteors or to look at the warmth of the ozone, high up in the atmosphere. Because, if we want to know the weather of tomorrow, we have to understand the atmosphere today.

Christoph Franzen with the all-sky-camera on top of the natural science building in Gløshaugen. This camera detects nights with northern lights to separate between effects from the aurora and from the light from the hydroxyl. Photo: Per Henning / NTNU

Looking at the darkest spot of the night sky
I’m specializing in the warmth of the hydroxyl molecule (OH) – which is mostly contained in a thin layer at about 90 km altitude, where northern lights have a strong influence as well. This altitude is already too high for weather balloons, so I’m using a Telescope, actually pointing it towards the darkest spots in the sky, and not towards stars, which seems rather pointless in the classical usage of telescopes.

But there we can see the very dim light that lies outside the visible range, which comes from the hydroxyl and changes with the temperature of the surrounding atmosphere. We are observing these differences via spectroscopy.This can give us new measurements of the temperature, and with a little computational effort, the density of the atmosphere at a height of about 90km.

Space weather and Earth weather
We find that the weather in this part of the atmosphere can influence long term weather and climate down here. Measurements like the ones we are doing, provide important input for future climate models and weather forecasts. With the research results from the research group I am a part of, we hope to better understand the Earth’s whole atmosphere and its natural variability.

Multitasking: a highway to self-deception


Asserting to ourselves that we work efficiently is something we strive for – it’s hard to beat the feeling of having been really productive after a long day at work. To accomplish this, it seems incredibly inefficient to just do one thing at a time while you’re working, doesn’t it. Why should you, when you can check your email or social media, eat your lunch, while writing a report and planning the important meeting you have tomorrow all at once.

Let’s pause for a second. How certain are you that juggling all kinds of activities throughout the day is the most efficient way to work?

It does seem impressive. Getting a lot of stuff done, more or less at the same time, has to be a remarkable feat. However, the research you’re about to get acquainted with might prompt you to reconsider.

Multitaskers worse at multitasking

Researchers at Stanford [1] and Ohio [2] university published a few years ago studies where they, among other things, compared the following two groups:

  1. Persons who multitasked heavily and who believed that doing so made them more efficient than others
  2. Persons who preferred to focus on one task at a time

As you might suspect by now, the second group accomplished to get more work done. But here’s the kicker: the researchers found that the persons in the first group, the self-confessed multitaskers, were actually worse at multitasking than those in group two! That’s gotta hurt.

It turns out our brains aren’t really built for multitasking. In fact, they are pretty terrible at it. The studies in [1] and [2] found that we become less productive and work more slowly when multitasking.


So why do we do it? The reason is that it makes us feel great: we think we’re being super efficient while in reality we’d be much better off focusing on one thing at a time.

Of course, there are plenty of activities outside of work that leaves us little choice but to multitask if we want to be successful. If you’re a professional e-gamer competing in real-time strategy games such as Starcraft or League of Legends or a chef preparing a complex dish for a dinner party of ten, you will never excel unless you can multitask like a hero.

But when it comes to doing scientific research or teaching, the studies in [1] and [2] suggest that there is little reason to multitask and that you are tricking yourself into thinking you are more efficient than what is really the case. I encourage you to have a look at these studies – they certainly made me repent and change my multitasking ways.

[1] E. Ophira, C. Nass, and A. D. Wagner. Cognitive control in media multitaskers. PNAS 106, 15583 (2009)

[2] Z. Wang and J. M. Tchernev. The “Myth” of Media Multitasking: Reciprocal Dynamics of Media Multitasking, Personal Needs, and Gratifications.
Journal of Communication 62, 493–513 (2012)


Nordic Five Tech students won with wind turbine

November 2015, students at the Master Program in Innovative Sustainable Energy Engineering (ISEE) won first prize for designing and fabricating a small-scale wind turbine and electrical generator.

The competition was held among 130 students from both NTNU and a team from the Technical University in Berlin. The students were challenged to design and fabricate a small-scale wind turbine and electrical generator. The group with best efficiency measured in the wind tunnel was awarded the prize.

This year students from the Nordic Five Tech Program won first prize, having the turbine efficiency higher than the NTNU teams and the TU Berlin team, who won the prize last year.

More information about the ISEE Program

“I cannot believe we won! In this competition, we could use the theory we have learnt to develop an actual small-scale wind turbine. This is result of hard work and we are proud of being in the Nordic Five Tech Program”
Sayantan Chattopadhyay, Mechanical engineer, MS. System Integration of Wind Power (MSISEE), NTNU

Participants in the winning NTNU team. From the left: Sayantan Chattopadhyay, Luis Carlos Guajardo Gonzalez, Feng Guo, Thomas Duc, Meadhbh Ni Chleirigh

The governmental proposes huge budget appropriations within renewable energy for 2016. In accordance with the governmental declaration the government suggests an additional strengthening of the research centers for renewable energies. Students from NTNU and Technical University in Berlin is already on it!

The Competition

This competition within the course divide students into groups of six pupils of varying backgrounds and academic levels, with the project of designing, simulating, constructing and finally testing their own small-scale wind turbine.

“Having the opportunity to work as a team with all the ISEE students was a great experience especially given our different backgrounds and nationalities; it was very interesting to see the other teams designs and tests, and I’m very happy to see that the hard work payed off at the end.”
Luis Carlos Guajardo Gonzalez, Mechatronics Engineer, MS. System Integration of Wind Power (MSISEE), NTNU

The interdisciplinary Wind Turbine Competition is part of the course “Energy from Environmental Flows” with Prof. Dahlhaug in charge in cooperation with Dr. Paul Thomassen (firm SIMIS) Prof. Trond Toftevåg. The course includes students from a wide range of academic disciplines. The course gives students knowledge within advanced aerodynamics, electromagnetism and electro machine design.

“The course presents theoretical and practical challenges that the future engineers will meet in their professional lives. Such training is extremely important. Which also can be inspiring and motivating in searching jobs within the renewable energy business or future research careers.”
Associate Prof. Trond Toftevåg, Department of Electric Power Engineering

About the Program

The Master’s program in Innovative Sustainable Energy Engineering is a collaboration between five of the leading technical universities in the Nordic countries (Nordic Five Tech) and University of Iceland (UoI). The NT-Faculty is hosting the Program.

The program gives you a unique opportunity to tailor your degree based on your academic interests.
You will get to study at two of the partner universities, spending one year at each. You graduate with a double master’s degree from the two universities.

State-of-the-art education
Innovative Sustainable Energy Engineering has an increasingly important role to play in order to ensure a sustainable future energy production. The program provides a state-of-the-art education in the fields of conventional and renewable energy sources like new power generation, solar energy, biomass energy, wind power, geothermal power, and energy utilization in the built environment by means of economically and environmentally sustainable systems and technologies.

The students that won the competition are enrolled in the study track called “System Integration of Wind Power” which is a collaboration between Technical University of Denmark (DTU) and NTNU. Students study their first year at NTNU, then the second year at DTU.

“The competition was a great experience, not only to get to know each other better but also to come together as a group and really try to do something innovative and new, and getting to test out our design in the largest wind tunnel in Europe was definitely a highlight.”
Meadhbh Ni Chleirigh , Electrical Engineer, MS. System Integration of Wind Power (MSISEE), NTNU, In the photo together with the rest of the team.


More details?

The research led to the implementation of an innovative blade design algorithm, derived from an adaptation of the Blade Element Momentum (BEM) theory and taking into account the variation of Reynolds number along the blade. Using a 6 pole radial flux permanent magnet synchronous generator to convert mechanical energy from the rotor into electrical energy, the complete turbine reached a final efficiency of 38, 96 %.

Testing their turbines this year, the students exceeded the expectations deduced from the in house turbine simulation software, Ashes. In particular, it has been found that the rotor efficiency exceeded 50 % in the region or operation around 1650 – 1750 rpm, confirming the relevance of this innovative design, and placing it firmly in the category of state-of-the-art rotor designs.

Understanding Quark Matter


We are looking into the very deep of the stars resulting from supernova explosions. Through our work, we have found a new way of understanding the interaction between quarks – the atoms’ smallest building blocks.

Atoms are the building blocks of matter. They consist of a nucleus with electrons moving around. The nucleus is built out of neutrons and protons (nucleons), which again are built out of quarks, see Figure 1. Quarks can have three different color charges (analogous to electric charge), red, green, and blue.

Figure 1. Building blocks of atoms.


Quark matter in neutron stars

When a giant star explodes, its core collapses. The protons and electrons essentially melt into each other, and a neutron star consisting mainly of nucleons is formed. Nucleons are extremely densely packed: A neutron star has a mass of 1-2 solar masses and a radius of only about 10km.
Or put differently, if a cricket ball were made of neutron star material it would weigh about 40 times the estimated weight of the entire human population.

Normally, quarks are bound in nucleons. However, when nucleons are squeezed hard enough together, the individual nuclei lose their identity, and the quarks move freely around. This is called quark matter.

As a result of the total collapse the neutron star has undergone, quark matter can possibly be found deep inside them. The properties of neutron stars depend heavily on whether quark matter is present in the core of the star or not.

How to understand quark matter

The quarks and their interactions are described by a theory called Quantum Chromodynamics (QCD). In practice, a direct application of QCD to calculate the properties of three-color quark matter is technically not yet feasible. Hence one must resort to models to simplify the problem.

From three colors to two

It turns out that we can use QCD directly to calculate the properties of quark matter, if we imagine a world where quarks only come in two colors. This technique is a numerical method and is called lattice simulations.

Adapted model

In a world of two-color QCD, we can compare quark-matter properties from lattice simulations with those from model calculations. In our recent paper (lenke) we have done exactly this. Generally, we obtain good agreement between the lattice results and our results.

Figure 2 shows one of the properties that we have calculated, namely the so-called Polyakov loop. This is a measure of how free the quarks are. Depending on the temperature, the Polyakov loop varies between zero for bound quarks and one for completely free quarks. The blue crosses are the data points from lattice simulations and the red curve shows the result from the model calculations, with uncertainty (yellow).

New insights in quark matter

It is straightforward to translate our model from two colors to three colors, and therefore we believe that our results ultimately will give us additional insight into quark matter in the real world and perhaps increase our understanding of neutron stars.

Figure 2. Polyakov loop as a function of the temperature from lattice simuations (blue crosses) and model calculation (red curve) with uncertainty band (yellow).


Our work is published in Physical Review D: Confronting effective models for deconfinement in dense quark matter with lattice data Authors: Jens O. Andersen (NTNU), Tomáš Brauner (UiS), and William R. Naylor (NTNU).





The traces of a two million year old supernova

Data from satellites searching for high-energy cosmic particles from space show several puzzling phenomena. This leads us to believe that the Earth is still being affected by a supernova explosion happening two million years ago.

Our Milky Way might be a dangerous place to live because of supernova explosions which happen somewhere in the Galaxy approximately every century. The blast wave of such an explosion would strongly damage life, possibly leading to a mass extinction on habitable planets within a distance of ten light years.

High-energy particles from a further, hundred(s) of light-years away supernova would still produce a noticeable (beneficial or harmful) effect on the biosphere.

This illustration of the region surrounding our Solar System shows the estimated location of the two-million-year-old supernova, lying close to the galactic magnetic field, that may have been the source for some high-energy cosmic rays observed today.


New article

In our recent article “Signatures of a two million year old supernova in the spectra of cosmic ray protons, antiprotons and positrons” we put forward the claim that such an event happened to the Earth around two million years ago.

We find several signatures of this event in the properties of high-energy particles filling the interstellar medium around the Solar system and reaching the Earth in the form of cosmic rays.

A cocoon of cosmic rays

The local supernova explosion has produced an expanding cocoon of cosmic rays and the Earth happens to be situated inside. We believe that it is the presence of this local cosmic ray cocoon that explains several peculiarities found in the flux of cosmic ray protons and also of antiparticles, such as positrons and antiprotons.

Experiments on the International Space station

In particular, we have showed that the large flux of high-energy positrons and antiprotons observed e.g. in the satellite experiment PAMELA and the AMS-02 experiment on board of the International Space Station can be naturally explained by a two million year old local supernova.

From space to the deep ocean

Complementary evidence for a recent nearby supernova explosion is contained in the deep ocean crust of the Earth: A previously found anomalous high amount of rare iron isotopes in a two million year old layer of the ocean crust might be a remaining of ejecta from the very same supernova producing the puzzling features we observe in cosmic rays.


The two main ways of producing silicon for solar cells

Quality versus quantity – the classical confrontation. You also find it within research on solar cell materials and the two main ways of producing silicon for solar cells, but the heart of the matter is the quest to produce a perfect crystal.

Let’s be unoriginal and begin this post using the starting sentence of 99% of the papers in the field: Silicon-based solar cells constitute more than 90% of the global photovoltaic market.
For the newbs, Wikipedia (our bible) defines today the photovoltaic effect as being the creation of a voltage in a material, upon exposure to light. Tomorrow’s definition may be different, but I guess it is a simple/efficient way of defining the phenomena.

The heart of the solar cell
The complete silicon solar cell production is divided in multiple steps. The forming of crystalline silicon ingots lies in the middle of the value chain, and is a critical step to achieve good quality solar cells. The ingots are formed by crystallization from the melt, and are either mono- or multicrystalline.

This blog-post will be focusing on crystalline silicon for photovoltaic, and will attempt on drawing a simple comparison between the two main material categories, mono- and multicrystalline silicon. I am aware that this is not the catchiest introduction… but please continue reading, this is more exciting than it sounds, I promise!

Professor Marisa Di Sabatino Lundberg (to the right) showing a monocrystalline ingot at the lab. Foto: Per Henning / NTNU
Professor Marisa Di Sabatino Lundberg (to the right) showing a part of a monocrystalline ingot at the lab. Foto: Per Henning / NTNU


Quartz crucible for silicon solidification. Foto: NTNU
Quartz crucible for silicon solidification. Photo:  Wikipedia

A perfect crystal

The brightest minds of the solidification group work at the Department of Material Science of NTNU to improve the quality of silicon ingots.

Whether mono- or multicrystalline: The challenge is to grow prefect crystals, containing as few irregularities as possible. The irregularities, or defects, lead to a drastic decrease of the output solar cell efficiency.


Multicrystalline silicon: Low quality, low cost

Multicrystalline silicon ingots are produced by directional solidification in crucibles  made of silica, and can weigh up to 2 tons. They contain a wide variety of imperfections, reducing their quality.

They are however relatively cheap to produce as the average multicrystalline silicon wafer price is around 1.0 $. These ingots have in addition a great improvement potential. Today’s production of silicon for solar cells is approximately 50% multicrystalline, and this ratio tends to increase over the years.

Due to the relative low quality of the material, the production costs determine the market shares, and China dominates outrageously the competition, as almost no multicrystalline ingots are solidified in Europe or US anymore.

Monocrystalline silicon: High quality, with a challenge
Monocrystalline silicon is mainly solidified using a method that has taken the name of its Polish inventor, Czochralski. This process is relatively more expensive (wafer price around 1.2 $); when successful, it leads to the production of cylindrical ingots up to 150kg.

Gaute Stokkan is a researcher at SINTEF, and has recently described these “sausage formed” ingots in Aftenposten, as being the most perfect thing humans have created.

4 billions of atoms arranged regularly in rows, with the same constant pattern and the same distance between each others. Improving the monocrystalline ingots quality certainly is a challenge! The moral is however high, and many researchers are still focused on eliminating the last remaining imperfections.

This high quality material represents a market niche for the countries where production costs are more important. Norway has in particular built a solid competence in Czochralski-silicon over the years, and two monocrystalline silicon solidification plants are found in the country, one in Glomfjord (Norwegian Crystals), and one in Årdal (NorSun).

Quality versus quantity – the quest goes on
… this is one of these confrontations. Both mono- and multicrystalline materials have their arguments, and are associated with different technological challenges and scientific problematics.

God knows what the future will be (pardon my religious tone here), but one thing is clear: the current situation certainly ensures a long life to research in the field of silicon solidification!