What if cities tomorrow were using all their waste as resources to the circular economy ? This would entail quite a dramatic change from the current – unsustainable – way of doing things. Instead of sending valuable materials to a landfill where they could take centuries if not millenia to degrade, they could be used to further benefit our communities.
According to data from the European Union, each EU citizen currently generates 505 kgs of municipal waste per year (or 1.38 kg per day!) and less than half (48%) of all this is either being reycled or composted. As seen from the image below, if recycling, composting and incineration have grown while landfilling as decreased drastically. But there is still a lot of things to improve on this topic.
Most municipal waste – except things such as batteries, electronics and so on that are taken care of separately – can be sorted out in three broad categories. Each can be seen as a kind of nutrient for the circular economy.
Food scraps, food waste and other putriscible materials such as yard waste can go to biodigestors or composting solutions. Anaerobic biodigestors collect methane which is burned as biogas to generate both electricity and heat in cogeneration plants.
Composting is another valuable solution to feed local plants, trees and even cultures. Valuable nutrients help plants grow and suck more carbon locally. Even better, compost can help rebuild poor soils damaged by intensive agriculture.
Even if the massive quantities of food waste were halved this decade as it is stated in the 12th UN Sustainable Development Goals, there would still be ample materials to generate biogas and compost as to date, in the European Union “nearly 57 million tonnes of food waste (127 kg/inhabitant) are generated annually with an associated market value estimated at 130 billion euros.” (source)
Papers, cartons, glass, metals as well as some plastics are all recyclable. After being properly sorted out they should be recycled and reused locally by industries that are building new materials. Recycling allows for cheaper, less energy intensive and less polluting materials.
Glass and aluminium can be reused and recycled ad aeternam, paper and cartons can be recyled or transformed into cellulose wadding insulation to make buildings greener and more efficient…
But these days, recycling has a lot of issues and some of it is not only being recycled but shipped to developping countries where it ends up in landfills. Mongabay has an interesting series of articles and podcasts on that very topic.
There I learned that “The European Commission estimates that the illegal handling of recycling and other wastes represents around 15-30% of the total EU waste trade, generating EUR 9.5 billion annually.”
All the rest should be burnt in waste to energy plants as it is done in Denmark. According to Politico, “Denmark is Europe’s top waste burner. Incineration accounts for about a fifth of district heating and about 5 percent of its electricity”.
Nowadays technology allows us to burn almost anything without having to fear nefarious air pollutants like dioxins. If a City- State of the level of wealthy Monaco is doing it, it is safe to say it can be done anywhere. An added benefit of this is that the heat generated can be used to heat nearby habitations and buildings in a sustainable way.
Of course, this solution is far from ideal, but we are not living in an ideal world. As we are drawning in waste, this should be seen as a stopgap measure until our societies evolve to produce much less waste.
This is why we need to improve the day to day practices by our fellow citizens – reduce, reuse, repurpose… This will take education as well as systemic change. Changing our laws, changing our daily lives are imperative if we are to produce much less waste. Doing so would make our communities and cities more sustainable and cleaner.