A coral reef with


Madelief Fisher: My CCell Experience

Madelief Fisher

by Madelief Fisher


Our latest intern, Madelief Fisher, reflects on her time at CCell and the lessons she will be taking with her.

Having just completed my high school education in the Netherlands, I had a free summer before starting university again in September. Due to Lockdown restrictions related to the Covid-19 pandemic this time had to be spent at home meaning I had lots of time to take on a new project. I also really wanted to gain some work experience.

A coral reef with

After two months with CCell our latest intern reflects on her experience

In secondary school I did all of the science subjects; Chemistry, Physics, Maths, Biology etc. and these have certainly always interested me. Add onto that my love of the sea; watching it, hearing the crash of the waves and especially swimming in it, CCell seemed the perfect fit.

The company immediately intrigued me; the concept was something completely new and it aligned with many of my interests. In the future coastal protection will become more and more important, especially with the climate crisis leading to rising sea levels and increased coastal erosion. Next to this the coral population of the sea is rapidly declining and are in great despair. CCell's technique for building reefs can bring about a huge positive change, helping to boost global coral reefs. Being conscious of the environment and the world around me, the fact that renewable energy is being used and the technology is nature-based, this coastal defence mechanism had a great appeal to me.


In my two-month experience at CCell Renewables I spend most of my time working on two big main projects. These were completely different, which was perfect because I could experience very different sides of the company and methods of working.

I started off on the physics side of the company, working with electronics. CCell works by using renewable electricity to power an electrolysis process that brings in natural seawater minerals around a steel frame. This makes rock which grows over time, providing a place to plant corals. In between capturing the wave energy, sometimes through a curved paddle but usually through solar panels or from wind turbines, and the reefs growing rock there has to be another step. This step controls the power that comes in and turns it into constant controlled power for the rock growth. To do this a Printed Circuit Board (PCB) along with numerous other parts and chips is used. You could think of PCB's as the brains of electronical products. Altium Designer is a program used to collect an overview of parts and design the PCB. My tasks included checking all schematics (diagram of the components), designing footprints and 3d-models, creating schematics for more complex boards and making summary tables. These tasks formed the basis for the further, more complex steps the rest of the team took later on. These included combining all schematics and making them fit together, like Tetris blocks, to create a schematic overview for the whole board on all layers. This can then be sent for manufacturing and used when assembling the PCB.

Altium design of a controll circuit on CCell's power management board

Part of the circuitry for our power board on which I was working.


Halfway through my internship I switched over to the chemistry side. Here I was working on a research project. This was based on figuring out the key relationships between rock growth and voltage, current etc... Research had already been done on this, but CCell wanted to properly model the relationships between different factors (temperature, pH, voltage etc) and the rock growth.

CCell grows rock on their steel reef shapes by passing a safe electrical current into them. Electrolysis takes place in the seawater, meaning both water molecules and chemicals within the seawater are broken down. At the cathode hydroxide ions are produced which react with calcium and magnesium ions. The preferable reaction is with calcium because this results in the precipitation aragonite (CaCO3) which is stronger than brucite (Mg(OH)2), and therefore a better material for the reefs. In this project I examined the different factors at work in the sea and how they affected the creation of aragonite and brucite.

This project made me get out my high school chemistry textbooks. Like all scientific research a lot of the work consisted of doing thorough literature research, mainly by reading/analyzing previous scientific papers. The process started with reading a paper, taking data from it, modeling or using data for calculations and testing the model against other findings/results. Quite often I would go into a certain direction, bump into a dead end and have to think of a different approach. A difficulty was the many dead ends because not a lot of experiments had been done in this exact area, for instance in directly telling how much aragonite rock will grow at a certain current. However, using the available data I eventually attempted to make a model, estimating percentage of aragonite rock growth in relationship to temperature, ion-concentrations, activation energy and current.


Working remotely and therefore not getting a chance to meet the team in real-life can be tricky, especially for an internship. In this case, the remoteness didn't have a disadvantage. The whole CCell team were very open and straight away gave me the feeling of being part of the team. As an intern I was allowed to participate in nearly every team meeting, and I learned a lot through this. Each morning would start with a group call to discuss what everyone had done the day before and was planning on doing that day. I think this is a great way of working, especially when everybody is restricted to working from home. It enhances the group contact and with help of a task board makes sure everybody is doing something useful. It was great to experience how a small company worked from the inside and how certain problems were approached.

Even with the remote working there was enough contact and everybody on the team was really friendly and willing to help when you needed this. Mostly I had direct contact with Will and Sam, since they were already involved in the projects I was working on. I had regular check-in calls and they both invested a lot of time explaining concepts and ways of working to me. A very positive aspect was the feeling that everything I was doing was useful to the company and a real task that had to be done, not just assignments to keep me busy. Some of the tasks were quite challenging, because most of the techniques and analysis were new to me and required a thinking step further than I had used when studying chemistry and physics. However, my understandings got greater with time and I learned a lot including how to use different computer programs (like Altium Designer), a little bit of python coding, a vast amount on doing proper scientific research and composing a useful literature overview. Next to these skills, which will certainly help me in the future, I also got a greater understanding on seawater electrolysis, coral growth and the way PCB's work.

A healthy coral reef with fish swimming around it.

Coral reefs form a natural barrier that breaks the waves. This protects the coastal areas from getting a heavy wave impact. Source: Nature

In conclusion I would say I am very happy with the opportunity to have had a two-month internship here with CCell. I believe it has prepared me a bit more for the future, by gaining skills and experience in the field I might end up in. After the summer I will be starting the university course Liberal Arts and Sciences. In this course you will have to work a lot in teams on projects and do lots of research and writing of papers. Having read through many scientific papers, analyzing them and searching for the most useful pieces of information, I believe it will help me during my further education. A fact I know for certain is that I will keep an eye on CCell, making sure not to miss exciting future developments.

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