Interview to Gerasimos Lyberatos for “Waste4Think”


 Waste4Think is a term that has been dynamically in our life in the last year and is expected to concern us even further in the near future. Why is there so much talk about this in our city? What reasons does Halandri boast of having integrated a European program into the local waste management plan? ; How does this city aspire to … remove its garbage by converting the excess of its food into alternative energy?

In these and other important questions, the municipal consultant and scientific officer of the Waste4Think program, NTUA Professor Gerasimos Lyberatos, said that the pioneering program soon came out of its pilot phase to gradually become generalized throughout the city.


Waste4Think-Horizon 2020 is a pioneering waste management program implemented in Halandri and three other European cities. What makes it so innovative and what are its benefits?

Waste4Think looks at modern and promising innovative waste management solutions. Especially in Halandri, we focus on the management of food waste, which accounts for a large proportion of the solid waste we collect, and until recently it was the only waste fraction that was not recycled. With the Waste4Think program, this material, which we collect by sorting at source, is converted, by drying and shredding, to a feasible biomass product, FORBI (Food Residue Biomass).

Such management, coupled with upgraded recycling into separate streams of blue and yellow buckets, is able to reduce waste resulting in landfills to less than 10% of their current amount. By the way, this reduces the cost of disposal and disposal of waste. “FORBI” can then be used either as a fuel in the cement industry or as a solid fuel pellet, as a biofuel gas or a mixture of hydrogen and methane for vehicle traffic – something to be tested soon as a municipal waste incinerator – as a liquid fuel (bioethanol) to be added to petrol, as a compost, as a feed or for the production of activated carbon for liquid waste. All these alternatives under the program will be evaluated and compared with each other for the most environmentally and economically advantageous. This approach is a global originality.

What is the importance of active citizenship in the process?

Citizen participation is crucial and the whole success of the venture depends on it. The “key” of this approach is kept by the citizen participating in the program and has the waste in a controlled manner in lockable bins. At the same time, the citizen becomes more aware of the issue of environmental protection and takes an active part in it.

How did the households that participated in the pilot phase of the program do so far?

The quality of the collected material after about one year of operation is excellent with less than 2% of misplaced material. The great success of our pilot project already leads us to design the next phase that will be the universal implementation in a municipal apartment- that is to say by increasing participation in 10% of the total population of the city. After completing this phase, we will be able to apply it to the entire municipality.

How much has Waste4Think benefited NTUA’s research on waste management for alternative energy production? What is the ultimate prospect?

We have been working on the use of organic materials for the production of biofuels at NTUA for many years. The application and development of these technologies to the organic (fermentable) fraction of municipal solid waste, through Waste4Think, leads to further development and optimization of these technologies. However, we must emphasize that Waste4Think was not created with the primary objective of being a pillar of support for NTUA research. The program is integrated into the local waste management plan of the city – voted unanimously by the city council – and exploits the expertise and experience of the NTUA with the ultimate goal of improving the quality of life in our city leading, coupled with the recycling of the two currents, almost to the elimination of waste. Already today, the ratio of green bins to recycling (blue and yellow) is 1 to 1 while in the past each 4.5 recycle bin corresponded to 4.5 green. The significance of Waste4Think is more elevated simply because it faces in the city with the cooperation of the NTUA the most difficult part of alternative management: bio-waste.

What does Halandri mean for the know-how and the culture it acquires through the implementation of the specific program?

Until recently, our municipality, like most of the country’s municipalities in the waste sector, was limited to collecting them. Through Waste4Think, which is part of the local waste management plan, the Municipality of Halandri acquires immeasurable know-how and plays a role in the treatment and recovery of waste, which is transformed by a garbage producer into a producer of products with great social, economic and environmental benefits, which were reported. A secondary but not negligible benefit to our city is also offered by the municipality’s involvement in a research project of international standards, which can significantly improve the quality of the services provided by the municipality to the citizen.