Category Archives: 2017

Your final good deed

A wooden casket with on top gorgeous floral arrangements is being carried across the cemetery. Followed by a procession of mourning silent people the casket arrives at the grave where tombstone marks the final resting place of the deceased. We want to give our loved ones a funeral they deserve. However, such “traditional” Western burial is the worst ways to dispose of a body.

The impact of a funeral

Reports of Netherlands Organisation for Applied Scientific Research (TNO) show that burial is the most stressful for the environment, followed by cremation. The least stressful is a technique called alkaline hydrolysis. With this technique the body is being dissolved under pressure in hot water with potassium oxide.

Watch this video on how alkaline hydrolysis works

In the reports the impact on the environment is indicated among other things in shadow prices. These prices are the costs that have to be made to compensate the effects of the funeral techniques on the environment in euros.

The total environmental impact of the funeral techniques is between €2.59 for alkaline hydrolysis and €50.83 for a burial for an average deceased person. Cremation lies between those two, €48.47.

With burials, the biggest factor of impact is the space it takes to bury someone, costing 19.26 euros to compensate. The second biggest factor is particulate formation, 13.44 euros, followed by water supply depletion, 10.58 euros.

The biggest factor with cremation is particulate formation, costing 18.37 euros. Also cremation has a big effect on the water supply, its shadow price is 10.35 euros. Eutrophication, the enrichment of a water body with nutrients causing loss of biodiversity and depletion of oxygen, comes third with a shadow price of almost 7 euros.

The shadow price of just 2.59 euros for alkaline hydrolysis doesn’t mean the process isn’t stressful for the environment. It means that costs are compensated. Some of the effects categories have negative values. The water supply depletion costs for alkaline hydrolysis are 4.53 euros, but the costs for human toxicity are -2.15 euros. Together with the negative value for particulate formation, -2.07 euros, and the values of other effects categories, makes that alkaline hydrolysis has a net shadow price of 2.59 euros.

Screen Shot 2018-01-14 at 20.37.20
The environmental impact in shadow prices of burial (left), cremation (middle) and alkaline hydrolysis (right) (TNO 2014 R11303)

So what to do?

Keeping in mind that an average burial costs between €8,500 and €11,000, why don’t we all choose for the greenest and much cheaper version? The main reason could be the fact it is not legal in the Netherlands. The research done by TNO has been conducted on behalf of Yarden, a Dutch funeral organisation and insurer. The aim of the research is to provide information needed to change the law regarding funeral techniques in the Netherlands. This law states that one’s body may be buried, cremated or donated to science.

The two funeral techniques apart from burial, provide the great advantage of being able to recycle metals which otherwise would be lost in the ground. With alkaline hydrolysis this advantage is extended to the capability of recycling noble metals. This recycling results in a compensation of environmental effects.

For now, we can only hope that when our time has come the law permits us to do our final good deed for this world.


This is what a energy-neutral Leiden look like.

Nowadays it’s a trend for every country, company, organisation and municipality to set as ambitious goals on sustainability as possible. Most of the time however, those goals are put on the back burner. The methods to reach the goals are kept vague and the goals are often not reached in time. The municipality of Leiden seems to be going down a different path.

Leiden also set some ambitious goals on sustainability. One important goal is to realise a netto energy-neutral Leiden by 2050. But, directly after setting this goal, the municipality of Leiden and the Dutch ministry of infrastructure and environment commissioned several companies and organisations to join hands and to develop an energy transition map of Leiden and its surroundings. This map shows a scenario of what Leiden would look like if this goal indeed would be reached by 2050. You can check out the map below.

map-leidenFor a bigger version of this map click here

This map clearly shows that the transition to an energy-neutral Leiden requires quite some rigorous changes. I’ll discuss the two most comprehensive ones here:

1. Complete new heating infrastructure

To reach the goal set for 2050, Leiden and its surroundings will need to get rid of fossil gas used for heating. Instead, there’s a need for a completely new heating infrastructure, fuelled by geothermal heat ánd waste heat from the Rotterdam industrial area. Realising this infrastructure will take an enormous effort. However, Leiden and some partners have already started the realisation of this network in a big project. Check out the video below to learn more about this project (in Dutch).

2. Placing hundreds of wind turbines

To generate enough energy to make Leiden energy neutral, a huge amount of energy needs to be generated inside the area. To achieve this, there need to be placed hundreds of wind turbines. In the scenario presented in the map, the wind turbines will create a thick belt through the area, ‘separating’ the urban area from the nature area. Some other wind turbines will be placed in the dunes, a almost sacred place for a lot of citizens. To convince people of the urgency of those placements as well as to fund this expensive project will probably be a tough task for the involved parties.


So to conclude, the municipality of Leiden took a bold step by developing this map which shows how radical the transition towards 2050 will need to be. This transition brings great challenges and I’m really curious on how Leiden will take these on.
What do you think? Will Leiden be able to reach their ambitious goal, based on the map that is presented? Can you find any underexposed solutions on the map? Feel free to let me know.

Cycling through a sustainable Leiden

The city council of Leiden is working on a liveable and promising city through the years.
At the moment they set up a plan for 2016 until 2020 to focus on a more sustainable city even more. The idea seems really nice, but the big question is: Will it be  achieved?

To realise such an achievement, you will need the contribution of the citizens.
Because they are the biggest player in the sustainable game. To make them act towards the sustainable plan of the council, you will first have to show them that it is really possible to do something for a more sustainable city.
And people in the city are allready on the right track actually!
I would like to give you a short preview on how citizens make Leiden more sustainable starting with a small contribution.

Everything in Leiden is very close to each other, this makes it very attractive for people to take the bike instead of their car. Actually almost fifty percent of the people takes their bike to go to work or school.
And that school part is very important in Leiden, because there are a lot of students living in the city. Almost every student has one bike (or more). But you would be a fool to buy the most beautiful bike you can afford, because the chance that it will be stolen is very high.

But a lot of students on crappy bikes also means a lot of bikes which break down. Those bikes will often not be repaired, because its easier to buy a cheap new bike.
Bikes that broke down will stay where they are, which most of the time means next to a canal (and after an amount of time end up in the canal)
Those bikes have a large impact on the environment because they release iron while rusting. Once a year these bikes have to be dragged out of the water, which costs a lot of money.

Two students in Leiden thought that something should be done about this problem.
They wanted to offer a very quick bike fixing service and also to stop waisting old bikes which aren’t used anymore. A new company arose at that moment, EasyFiets.
They started to collect old bikes through the city which owners could address themselves. Those bikes were repaired and put back on the market again for leasing, or renting for a day. You can easily recognise them on the red handles and saddle. 

Remarkable red saddle and handles (EasyFiets)

This is an example of a small start to contribute to a circular economy.
Ofcourse not all the old bikes will be collected by the company and re-used. But still, once you know about the concept you see the remarkable bikes everywhere you go.And every time you see one, you will be remembered about the easy way to contribute to a more sustainble city.

It’s only one example of a contribution by citizens, but ofcourse there is more. This example is just to show that people are willing to change and work with the council to make the city of Leiden more liveable and promising.


Leiden: Leading in sharing

Modern problematic

Living in a modern world we, as human beings, have exceeded our potential of connecting to (and sharing with) one another by the means of internet, smartphones and most of all an intensive use of social media. Despite its underlying philosophy of bringing people together and creating a sense of community, people still are feeling lonelier than ever and feel more unsafe than they did in earlier times. Even though the latter might be true looking purely from an environmental perspective, one could say we live in prosperous times in which the world is safer than it ever was before. To kill two birds with one stone, moving towards a sharing economy can contribute to a sustainable future while recovering our sense of community and feelings of safety.

How a sharing city works

Basically, a sharing economy works according to the principle of sharing products or services through the concepts of peer-to-peer or peer-to-business-to-peer sharing or renting (such as Airbnb). In doing so, it can reduce the demand for new products and therefore reduce a populations resource consumption. Furthermore, the sharing or temporarily trading of a product or service with ones close by neighbors would result in more communal solidarity. When implented on a large scale in a city, we can speak of a sharing city. As a leading example, Seoul is currently the front-runner on becoming a sharing city. They have implemented interesting ideas such as:

  • Using “sharing libraries” where people could deposit and borrow tools or books for free.
  • Car Sharing
  • ShareHub: a place to find all that can be shared.

The transition towards a sharing economy isn’t only happening in South Korea, but also here in the Netherlands in both Nijmegen and Amsterdam. One could argue that if Amsterdam could implement innovative ideas towards becoming a sharing city, Leiden could most certainly succeed just as well. As Leiden is a lot smaller and less, the possibilities are endless to make the transition.

Leiden towards becoming a sharing city

To make the transition towards becoming a sharing city one could think of several applications in the city of Leiden. For starters, Leiden has a lot of empty buildings that could function as sharing hubs or as headquarters for startup companies that could work on the transition. For instance, the old V&D building on the Nieuwe Rijn/Breestraat which is now being used for pop-up stores could be the new center of sharing. By dividing this massive building into separate supervised corners which all have an own product category (e.g. tools, clothes, electronics), you create an accessible and fundamental place for sharing.

Another way of making it possible for Leiden to become a sharing city is by developing an overarching website or app which includes all categories of products and services which could possibly be shared among the city’s citizens. By including as much companies and students in the development of this application as possible, and by sharing the service throughout the city’s universities, popular visited locations and through the inhabitants mailboxes, this application might result an a success.

To make the transition towards a sharing economy lot of extra services will need to be implemented to make it a succes. For instance, a workforce that examines the products for any damages to a persons product needs to be implemented. Next to that, people would want to be sure that their product always returns to their rightful owner, meaning that people would have to register to be able to share or borrow a product. Of course the transition towards a sharing economy isn’t something that happens overnight and takes time and effort (meaning job opportunities!) to make it all possible. Nevertheless, a sharing economy is an interesting concept that could change our end of life economy  to a more communal and sustainable way of living.

The city as goldmine of both materials and knowledge

What’s wrong?

Today, production and consumption of goods in all corners around the world is more extensive than any time before.1 The problem is that our global economy has always been a linear system. We extract raw materials, transform it into something useable and then, after a relatively short lifetime, turn it into waste. But what if I told you that we no longer have to extract raw materials from Mother Earth and have the opportunity to turn our waste into a resource? Intrigued yet?

That sounds better!

Fortunately, businesses are innovating a new industrial paradigm: closing loops. The driving force behind this? Our economy is approaching a tipping point where the old take-make-waste business model is a dead end. Finished, finito and no longer lucrative. Businesses are forced to rethink their products, as the global population is growing and urbanizing and resources are not infinite.

What do cities have to do with this?

Taking into account that cities accommodate a vast amount of the people that design, create and use these products that are eventually thrown away, I argue that cities cover a great part of the solution to make these products available for reuse. Half a century ago, urbanist Jane Jacobs already exclaimed that “cities are the mines of the future”. This approach of urban mining is seen as a way to recycle metals from city waste like buildings, infrastructure and devices.2 The resource stock that has been mined from underground into the human society now has a chance of circularity. Let’s see what’s in this for Leiden!

“As a city of knowledge and innovation, Leiden should be a frontrunner when it comes to sustainability” – Leiden Duurzaam 2030

Abuse the city’s students!

Life in Leiden is highly influenced by the relatively large number of students, as most of them live and study in de city.3 I have always believed that students can offer great help in society’s contemporary problems when it’s in their field of expertise. Because, as cheesy as it may sound, today’s students are tomorrow’s future. And other than that, it is both cost effective and awesome for municipalities or companies to collaborate with a university or a particular group of students.  When you ask students to get the job done you don’t have to hire an over-priced consultant and you are guaranteed that quality will be delivered, as these students will be advised by the country’s best-educated people: their professors.

Can you get back to the point?

Linking the latter story to urban mining in Leiden, there are a couple of things that can be done. Since students are the future’s leaders, scientists, inventors, entrepreneurs and engineers, it’s clever to get them to work together from a systems perspective. We are still counting on technological advancements, pollution-control technologies and public awareness when it comes to determining what forms of urban stocks exist, when these urban stocks will become available for reuse and how these can be reused.

N.B. I would like to remind the municipality and/or companies not to forget to reward these students with an excessive amount of ECTS.


1 J. Li (2015) Wastes Could be Resources and Cities Could be Mines. 

2 P. Brunner (2011) Urban Mining A Contribution to Reindustrializing the City.


Generating energy; what other sustainable options are there besides solar and wind energy?

When we think about generating energy in a sustainable way –thus no use of fossil fuels- most people think about solar panels and large (ugly) windmills. Of course not without a reason, because both options have already been proven to be very efficient and have become cheaper and better every year. But to generate energy there are so many other nice possibilities that each have their own set of extra benefits. It would be a shame to neglect these options.

What about all the people that work there asses off in the local gym? Why is the power generated by all their hard work not being used to burn our lights yet? About 20 % of the population in the Netherlands over 15 years has a gym membership.That’s about 3.2 million people if they all run say, one hour per week on a treadmill. That would already be 3.2 million*52 hours= 166.4 million hours on a treadmill. One hour on a treadmill gains you about 400 watts. So that’s 166.4 million *400 watt. That can be used. The bonus here of course is that people also get healthier!

Honey, I’d like to charge my phone tonight, could you please go on the treadmill this time?

Another idea could be to take an advantage out of our ageing problem. We have more and more elderly people with failing body’s like for example incontinence. In Japan diapers of elderly people are being used to recycle the paper and plastic from the diaper, but they have found a system which can separate the faeces in the diaper and use the methane to heat the roads or to heat greenhouses.

Japans system of diaper energy

Or what about energy generating speed bumps? We have tons off them in the Netherlands so why not implement an energy generating system out of those annoying car wreckers.  In England they have already started installing ‘’electro-kinetic road ramps’’ as they are romantically called. The bump contains some kind of a metal plate. Whenever a car drives over the bump an internal generator will be powered. Of course it depends on the weight of the car and the passenger (do they generate energy as well in the gym or not?) how much kilo watt the bump generates, but it can go up to 50 KwH per vehicle! All this energy could be used by traffic lights for examples of LED road signs

As my last example of multi-beneficial sustainable energy generating I would like to give some attention to a quite simple implementation that Sweden did. They use confiscated alcohol, which would normally be poured down the drain, as a way of generating energy. How amazing is that! In the Netherlands we have a lot of festivals every year, where people bring their own booze. And although I am sure that many people actually can smuggle their alcohol into the venue, there are also enough that get caught. In Sweden the alcohol they confiscate (700.000 litres last year) is converted to biogas and will subsequently be used for trucks, buses and trains.

And there are so many other bizarre ways of generating energy that could be used. In a sense everything that moves, contains energy. In my opinion it would be a waste to not use all these options that are already there anyway. We just need to make some slight adaptions. And most importantly we need to keep thinking out of that box!

Solar power, answer for Leiden’s renewable energy source?

Our primary energy generation still relays on fossil fuels. Approximately 80% of the world’s energy supply comes from fossil fuels. However, fossil fuels will soon or later depleted. Therefore, energy generation by non-fossil fuels should be implemented on large scale. Solar energy has a large potential to generate a considerable amount of energy in the world. The potential of solar energy can be seen in figure 1.

Figure 1. Solar energy potential in the world.

Energy generation still also relays primarily on fossil fuels in The Netherlands. In 2014 only 5.5% comes from renewable sources. The government has set a target of 20% renewable energy sources in 2020. In the next coming years we have to increase our renewable sources by 14.5% of our total energy generation. Currently, biomass and wind energy accounts for the majority of renewable energy in the Netherlands. Solar power has relatively a small share in comparison to biomass and wind energy. This can be seen in figure 2.

Figure 2. Shares of renewable energy sources in the Netherlands.

However, in recent years the use of solar power has significantly increased from 88 MW in 2010 to 1405 MW in 2015. Solar power will contribute a significant amount of renewable energy. In order to reach the target of 20% renewable energy sources in 2020, solar energy has to expand in The Netherlands. Solar power has potential to generate energy as can be seen in figure 3.

Figure 3. Solar power potential by annual sun hours.

The potential is not that high as in countries with more sun hours per annum e.g Australia. However, Germany installed an enormous number of solar power systems. In 2015 the installed capacity was 40782 MW.[i] This accounts for approximately 7% of the total energy generation in Germany. The amount of solar energy generation is almost neglectable. Germany has a similar sun energy potential as in the Netherlands; we have a similar climate and sun hours per annum. Therefore, it is likely to implement similar solar systems in the Netherlands as in Germany to increase the share of renewable energy sources.

Solar energy has a small share in renewable energy in the Netherlands. However, let’s zoom further in local municipalities in the Netherlands. The city of Leiden has an ambitious target to reduce CO2 emissions by 40% compared to 1990 in 2030. They also want to increase the use of renewable energy sources. The percentage of renewable energy was 6.1% in 2014 in Leiden according to klimaatmonitor. The share of renewable energy usage is slightly higher than the national average. However, Leiden has less solar polar per inhabitant than the national average. This can be seen in figure 4.

Figure 4. Comparison Leiden-the Netherlands solar power per inhabitant

This suggests the city does not invest enough in solar systems. According to figure 3 Leiden has a higher solar potential than other cities in the Netherlands. Moreover, Lots of roofs are suitable for installing solar panels. In order for Leiden and the Netherlands to reach its targets, solar energy could attribute significantly more to renewable energy sources than our currently capacity of solar energy.