At Greenfish, we actively look for the latest innovations and trends in sustainability. Each month, we organise our Impact Sessions, a sort of mini conference that aims to share knowledge and debate with specialists on sustainability-related topics. This is an opportunity for our consultants to learn more about their field and feel more integrated into our Greenfish community.

Our #5 Impact Session took place on the 20th September at Greenfish’s headquarters in Brussels. As guest speaker, we had the honour to welcome Hervé Jeanmart, teacher at UCL. Topic of the presentation was focused on “A 100% renewable energy world in 2050”.

From 1965 to 2015, the population has been multiplied by 2,2 and our primary energy consumption by 3,7: we consume more than what we need. During his presentation, Hervé Jeanmart explained that if we want to solve the climate issue, not only do we have to change the way and the quantity of energy we’re consuming, but we also have to switch from fossil energies to renewable ones. Electrifying the system helps reducing primary energy use and develop renewable energy.

Worldwide, going to 100% renewable energy for all needs seems feasible, relying mainly on wind and solar. Looking ahead to 2050, many countries intend to use wind as prominent energy source. Predicting a realistic maximum yield of onshore and offshore wind will play a key role in establishing what technology mix can be achieved, specifying investment needs and designing policy. But the number of facilities to build is huge, raising the question of practical feasibility. For Belgium only, a move to nearly 100% renewable electricity implies already 300km2 of PV panels and 2.500 wind turbines (5MWe each) in 2050. This scenario demands a huge effort in term of investments, and takes as an assumption that energy demand won’t rise between today and 2050, which in fact will probably not be the case.

The quality of energy facilities can be assessed using the EROI (Energy Return On Investment) and the NE (Net Energy) analysis. The EROI depends on the technology with renewable energies on the lower side. It depends also on the exploitation rate of a resource and on the technological progress. The worldwide wind potential is heavily affected by the EROI threshold.

Finally, Hervé Jeanmart explained that there is at strong link between energy and economy. Efficiency is increasing (and intensity is decreasing) but with diminishing returns. As GDP and energy consumption are highly correlated, we won’t be able to economically grow furthen than what our energy supply allows us to do. Another paradox is that energy efficiency won’t help us in that regard, since the money saved thanks to energy efficiency will be spent to consume energy in other ways (buying a news car or going on holidays by plane …).

Below a given EROI threshold, our society would not be able to maintain what we take for granted. By taking the dynamics of the EROI into account, the total energy yield is sooner or later decreasing, as also predicted more than 40 years ago…

Next impact session will be held today, the 02nd of October, with Raymond Bradley talking about the climate: “Where do we stand on global warming?”