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De meningen ge-uit door medewerkers en studenten van de TU Delft en de commentaren die zijn gegeven reflecteren niet perse de mening(en) van de TU Delft. De TU Delft is dan ook niet verantwoordelijk voor de inhoud van hetgeen op de TU Delft weblogs zichtbaar is. Wel vindt de TU Delft het belangrijk - en ook waarde toevoegend - dat medewerkers en studenten op deze, door de TU Delft gefaciliteerde, omgeving hun mening kunnen geven.

Posts by Roy Meijer

Julian Hunt on #COP17: How good was this deal really?

This opinion piece by Lord Julian Hunt was first published in The Independent on Monday 12 December 2011. Lord Julian Hunt is a visiting professor at Delft University of Technology, and vice-president of Global Legislators Organisation (Globe)

Developing countries insist their economies must grow before cuts to emissions

The current estimate for global temperature rise by 2100 is 3.5C. This is a devastating conclusion that underlines why many people, including myself, believe global warming represents the biggest threat to mankind. Continue reading

‘Rare earth’ policy omission threatens European prosperity

By Dirk Jan van den Berg and Erik Offerman
Dirk Jan van den Berg was the Dutch ambassador to China and is now president of Delft University of Technology (TU Delft).
Erik Offerman is an associate professor in material science at TU Delft.

This article was first published in The European Voice on 29th September 2011.

China is an unreliable supplier of vital materials, write Dirk Jan van den Berg and Erik Offerman. So Europe needs to find a response.

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Moeten we duurzaamheid integreren in het onderwijs?

Ellen van Bueren

Ellen van Bueren is Universitair Docent aan de TU Delft en editor van het leerboek ‘Sustainable Urban Environments: an Ecosystem Approach’ dat september 2011 bij Springer is verschenen. Deze tekst is de volledige versie van het opiniestuk dat in Cobouw is gepubliceerd onder de naam Duurzaamheid in onderwijs bijzaak (Cobouw, donderdag 22 september 2011)

Wereldwijd was het Green Building Week van 19 t/m 23 september 2011. Nederland deed dit jaar voor het eerst mee met de Dutch Green Building Week. Waarom was deze week eigenlijk nodig in Nederland? Weten we nog steeds niet hoe we duurzaam kunnen bouwen? Ja en nee, is het antwoord.  We weten het wel, maar we doen het niet, althans, we doen minder dan dat we kunnen. De kloof tussen koplopers en peloton, die al ten tijde van het kabinet Kok I werd geconstateerd, lijkt nog immer te bestaan in Nederland. En dat heeft ook te maken met de positie van duurzaamheid in ons onderwijs. Zolang duurzaamheid geen onlosmakelijk onderdeel uit maakt van ons onderwijs, kun je niet van studenten verwachten dat ze in hun werkzame leven die integratieslag wel maken. Maar zijn we al toe aan die integratie? En wat zijn de consequenties van zo’n integratie of het uitblijven daarvan? Continue reading

Dutch cities not prepared for climate change

Why we need to move towards climate-robust solutions

Dutch cities are ill-equipped to deal with climate change. Meanwhile the chances of damage due to floods, draught and excessive heat are increasing. In addition to material damage to buildings, infrastructure and green spaces, public health is also at risk. If we do not start to take measures now, the costs for governments and citizens may run up to billions of euros. 

 

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Why volcanoes are likely to continue to cause chaos in Europe

This article by Dr. Andy hooper was first published on Reuters The Great Debate on June 3rd 2011

Within the space of just over a year, aircraft have now been grounded in Europe twice by ash blowing in from Iceland.  This has caused many millions of pounds of disruption.

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EHEC en water

Prof. dr. Gertjan Medema, KWR Watercycle Research Institute & TU Delft

De uitbraak
Sinds begin mei is een grote uitbraak van nierfalen (Hemolytisch Uremisch Syndroom  of kortweg HUS) en darmbloedingen gaande in Noord Duitsland die wordt veroorzaakt door een Entero-Hemorrhagische Escherichia coli (EHEC). Op 3 juni waren in Duitsland 1733 gevallen van EHEC bekend, waarvan 520 HUS hadden ontwikkeld. De ziekte komt overal in Duitsland voor, maar vooral (72%) in de vier Noord Duitse deelstaten. De EHEC is ook aangetroffen in mensen uit andere landen (Zweden (28), Denemarken (10), Frankrijk (6), Nederland (4), Engeland (4), Zwitserland (3), Oostenrijk (2), de VS (2), Noorwegen (1) en Spanje (1). De uitbraak is nog aan de gang; elke dag worden er nieuwe gevallen gemeld. Eerder werden vooral (>90%) kinderen getroffen door HUS, nu zijn het vooral volwassen (88%) vrouwen (71%) waar de ziekte zich manifesteert. Achttien mensen zijn tot nu toe overleden aan de uitbraak.

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Wie ruimt het ruimtepuin op?

Dit opiniestuk van Ron Noomen, universitair docent TU Delft verscheen op 26/04/11 in Trouw
 
Na vijftig jaar ruimtevaart heeft de ruimte dringend een grote schoonmaak nodig. Er zwerft enorm veel puin, van afgedankte satellieten tot handschoenen van astronauten. Dat kan actieve satellieten knock-out slaan.

De vijftigste verjaardag van de eerste bemande ruimtevlucht is uiteraard aanleiding voor een groots feest. Maar het is een gouden feest met een zwart randje: de directe omgeving van onze planeet Aarde is niet meer de lege ruimte waarin Joeri Gagarin z’n rondjes kon draaien.

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Grondstoffen leerstoel waard

Dit opinieartikel van Dr. ir. Erik Offerman en prof.dr. Barend Thijsse verscheen op woensdag 13 april 2011 in FD Optiek. Offerman en Thijsse zijn verbonden aan de afdeling Materials Science & Engineering van de TU Delft

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A nuclear third way

This article by Julian Hunt and Graham O’Connor first appeared in The International Herald Tribune on Friday, March 25, 2011

Lord Hunt is a former fusion technology researcher, and a visiting professor at Delft University of Technology in the Netherlands. Graham O’Connor is a former senior scientist at the ITER (International Thermonuclear Experimental Reactor) project in France.

Nuclear power is here to stay, and the debate over its future should include ‘hybrid’ reactors.

The Fukushima disaster has inevitably prompted concern in many countries about nuclear power. But are the correct questions being asked?

A danger in the debate is that nuclear is often portrayed as a single, undifferentiated energy source. This is not only wrong, but also risks losing the opportunity we have to debate the role that new technologies – not only of fusion and fission, but also hybrid methods – can play in the energy mix in the 21st century.

Indeed, those who seek to write nuclear off completely are missing what could be extraordinary, breakthrough developments on the horizon with hybrid technologies that might – relatively shortly – completely reshape the way we think about nuclear energy.

The starting point for debate, for friends and foe of nuclear alike, should be the daunting energy problems many governments face. With growing challenges to energy security, the range of energy sources must be broadened, with greenhouse gas emissions reduced because of global warming. There is also a pressing need to reduce air, water and land pollution by coal and oil extraction and combustion (which continue to cause more deaths per year than nuclear power has in its entire history).

Renewables are a key part of the solution, but no country can be sure of the reliability of energies such as wind or solar in 20 to 50 years, given changed climatic conditions. Relying on neighboring countries for power also carries risks.

There seems to be no alternative but to include nuclear in the energy mix for at least decades to come. So, what do new generations of fission, fusion and hybrid offer?

• Fission
Modern power stations using fission, which harnesses energy from the radioactive decay of uranium and other fissile materials, are considerably safer than older ones such as Fukushima – constructed 30-40 years ago. This is because of stronger containment structures, more secure storage of spent fuel rods and emergency systems to prevent overheating. Further developments over the next 20 years will also reduce volumes of radioactive waste.

Because the supply of uranium may be limited, there are longer-term, controversial plans in some countries to construct ”fast breeder” reactors to recycle waste and use the fuel more efficiently. However, there are proliferation dangers associated with the plutonium byproduct.

Fission will only continue to be acceptable if the immediate risks of the current and planned systems are reduced. Despite improved safety, the rare, but catastrophic failures of technological and human operations such as Chernobyl cannot be dismissed. As Fukushima showed, there are also remaining risks from earthquakes, tsunamis, severe storms and even aircraft crashes – plus the dangers of fission associated with the storage of waste for over 10,000 years in geological repositories.

• Fusion
The principle of controlled thermonuclear fusion is to extract energy from processes similar to those occurring inside the Sun, where hydrogen atoms are fused together to form helium. This is a ”clean” process with negligible long-lived radioactive waste.

However, because of the great size needed for a ”pure” fusion reactor and the unsolved problem of fabricating materials to withstand the heat, the development challenges are substantial and may take decades to overcome.

• Hybrid
The long-term future of nuclear may lie with a still-little-known third option: combining nuclear fission (atoms splitting) and fusion (atoms merging) in a single ”hybrid” reactor. Indeed, without publicity, governments, agencies and research institutes are already moving tentatively in this direction.

Hybrid fusion was first proposed by the American Nobel laureate Hans Bethe to enable more widely available reserves of nuclear fuels other than uranium, such as thorium, to be used. Hybrid could become a reality within the next two decades – the Institute of Plasma Physics in China is planning to build a proof-of-principle prototype experiment by 2025.

The basic principle is that neutrons generated by fusion in the plasma core stimulate fission in the outer ”blanket” that contains uranium or other fissile materials (which could include nuclear waste). Because there is relatively less energy extracted from the plasma than in pure fusion, continuous operation can be engineered more readily.

The fission is well below critical mass and only operates when there is a current flowing in the plasma. This is why the system is safer.

The technology of maintaining the hybrid reactors has many advantages, and it uses a wider range of fuels. They do not produce the long-lived waste produced in fission because the high-energy neutron flux from the fusion process ”transmutates” these into isotopes that decay over a hundred rather than tens of thousands of years.

Not only does this eliminate some nuclear waste problems; it helps to rid the world of plutonium and other weapons-grade materials. Furthermore, if thorium is used, it cannot be converted into weapons-grade uranium.

While even modest-sized hybrid reactors could provide affordable and almost limitless energy, their power output can be controlled through the fusion process. Thus the operation is safe enough for a power station to be located even in countries prone to natural hazards.

Furthermore, the controllability would allow fusion-fission power to be used either as base load or more flexibly in combination with renewable energy, which is inherently more variable.

Many aspects of hybrid nuclear require further intense research – and economic analysis. Current collaboration between groups in Russia, China, the United States, South Korea and Britain needs to involve more countries.

While workable hybrid technology is still some way off, timeframes could be accelerated with the right commitments from the public and private sector.

This ”third nuclear way” deserves much wider understanding and support from governments, scientists, engineers and environmentalists alike if we are going to have the maturity of debate we so badly need about the role that nuclear can play in the energy mix over decades to come.

Domino-effect Japan kan ook in Nederland voorkomen

Dit artikel verscheen op WaterForum op 22 maart 2011

De gevolgen van de tsunami in Japan strekken zich uit tot ver buiten het getroffen gebied en treffen kerncentrales en de nationale energievoorziening en economie. Ook bij een watersnood en andere grote rampen in Nederland zijn zulke keteneffecten te verwachten, stellen onderzoekers Bas Jonkman (TU Delft/University of California, Berkeley) en Ties Rijcken (TU Delft).

Lees verder op de site van WaterForum.

Update 28 maart: Ook Cobouw besteedde aandacht aan dit onderwerp: ‘Effecten tsunami kunnen ook in Nederland voorkomen’

© 2011 TU Delft