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CML's Stans Award 2021

CML grants three Stans Awards each year, known as the best PhD paper, best student thesis and best outreach from the past year. The CML staff nominated students and colleagues and this year’s jury Prof.dr. Koos Biesmeijer and Prof.dr. Nicole de Voogd made the final decision.

Chengjian Xu

Best PhD paper 2020

This years winner is Chengjian Xu, he won the prize for the paper 'Future material demand for automotive lithium-based batteries'. Chengjian started his PhD in September 2018, so just entered his third year. 


The world is shifting to electric vehicles to mitigate climate change. Here, we quantify the future demand for key battery materials, considering potential electric vehicle fleet and battery chemistry developments as well as second-use and recycling of electric vehicle batteries. We find that in a lithium nickel cobalt manganese oxide dominated battery scenario, demand is estimated to increase by factors of 18–20 for lithium, 17–19 for cobalt, 28–31 for nickel, and 15–20 for most other materials from 2020 to 2050, requiring a drastic expansion of lithium, cobalt, and nickel supply chains and likely additional resource discovery. However, uncertainties are large. Key factors are the development of the electric vehicles fleet and battery capacity requirements per vehicle. If other battery chemistries were used at large scale, e.g. lithium iron phosphate or novel lithium-sulphur or lithium-air batteries, the demand for cobalt and nickel would be substantially smaller. Closed-loop recycling plays a minor, but increasingly important role for reducing primary material demand until 2050, however, advances in recycling are necessary to economically recover battery-grade materials from end-of-life batteries. Second-use of electric vehicles batteries further delays recycling potentials.

Best outreach 2020

This year we have a winning team for the Best Outreach prize. Sam Boerlijst, Lois van Laere, Amy Montanje and Megan Verhagen made and published the book “A Pocket Guide to Animal Asses of East Africa”. So far they have sold over 270 books and we’ve heard they are already working on the next pocket guide!   

Summary of the field guide

Most field guides require the animal to stand still to be determined up to the species level. In reality, a lot of these animals are quite shy: they run off upon being approached, leaving you wondering to what species that fine ass belongs. This extensive field describes a third of East Africa’s most commonly encoutered mammals, as well as some other creatures. It includes an easy method to discern them based on their behinds, and provides interesting fact about each species. A must-have for biologists eveywhere and a great introduction for all other nature enthousiasts! - Determination key based on buttocks & all their characteristics - 50 species, each comprehensively described (including diet, size, occurrence and fun facts) - Descriptions of all 27 animal families included with added illustrations.

Bas Roelofs

Best student thesis 2020

Bas Roelofs was one of our Industrial Ecology Master students and he won this years student award. During the awards he briefly introduced us to his thesis: "Material Recovery from Dutch Wind Energy
A dynamic material flow analysis on Dutch wind turbines towards 2050 including recycling approaches for recovery of key materials."


The transition to a renewable electricity system requires more intensive material use, causing problem shifting in environmental impacts. To conserve resources for the future and mitigate environmental impact, circular economy principles are needed. This study analyses material flows in Dutch wind energy towards 2050 to identify the potential for material recovery. This reveals material demand, stock, secondary material supply and required recycling infrastructure within environmental and economic context.
Inflows or demand for materials is increasing rapidly due to strong expected growth in the near future (2023), additional inflows are required after 2030 for stock maintenance. Outflows fluctuate, partly due to an early peak in onshore decommissioning and late peak in offshore decommissioning caused by a more mature stock of onshore wind turbines and currently developing stock of offshore wind turbines.
The outflow of scrap materials is used to determine secondary materials through various recycling routes. Due to partial foundation removal, a hibernating stock is expected for structural steel that increases towards 0.5 Mt in 2050. Composite waste management in wind energy is a major challenge as closed-loop recycling of composites is not feasible. The cascading effect of material quality results in low-value materials, with varying potential demand. Repurposing of blade segments requires minimal processing and could be implemented at present. Dutch wind energy could exclusively provide sufficient composite scrap material to run industrial-scale mechanical grinding after 2030 and pyrolysis facilities after 2040. Critical materials include vanadium, magnesium and rare earth elements. Secondary supply through recycling can mitigate this criticality by providing up to ~15% of REE, ~30 of V and ~25% of Mg demand by 2050.
This research is a first step towards circularity goals in 2050 and provides a sense of scale and timing for material demand, secondary supply and required recycling infrastructure for Dutch wind energy.

Full thesis can be found here.

Stans Award

At the initiative of one of the Environmental Science students, Dr. Constance Eikelenboom, an ecotoxicologist then nearing her retirement, in 1986 the CML Students Award is created as a motivational prize for exceptional publications. As Ms. Eikelenboom is known informally as ‘Stans’, it’s soon termed the Stans Award. It’s awarded annually and throughout the years it turned into three prizes, as we know them today: best PhD paper, best student thesis and best outreach from the past year.

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