Solutions to produce clean energies are multiplying. And if they have a positive effect on the environment, some of them still have a heavy liability.
Climate change is forcing manufacturers to invent new technologies in order to make our way of life less polluting. Thus, the production of electricity, our movements and our food consumption are now judged through the prism of their energy impact.
In recent years, the so-called “non-polluting” technologies such as wind turbines, solar panels and electric cars have exploded. And while these have a lower ecological impact than traditional technologies, they are not completely neutral.
Heavy metals in wind turbines
Wind turbines, for example, provide renewable energy as they use wind, just as solar panels take advantage of sunlight. But if these technologies, once installed, seem to have a positive impact, that their manufacture, on the other hand, is very different.
Thus, solar panels are made from a rare metal, silicon, whose extraction uses many complex chemical processes and requires to go for the metal in the middle of the rock. To do this, the use of machines operating with fossil fuels is necessary.
Likewise, magnets that rotate wind turbines are also made from rare metals, such as lutetium. To obtain a kilogram of this metal, 1,200 tons of rock must be extracted.
Urban hives compete with wild ones
Similarly, the installation of hives in urban areas starts from a good feeling, with the will to repopulate areas that suffer from the gradual disappearance of pollinating insects. Especially since the city centers are gradually blooming again and they offer to the bees a particularly favorable ground of life.
Yes but everything is not so simple. Because city bees and their wild cousins are in fact completely different species, with distant lifestyles. And the different species end up competing, the amount of available flowers is not extensible.
Many scientists therefore call for caution when it is decided to implant hives in cities, in order not to precipitate the extinction of different wild pollinators.
Essential desalination, but …
The environmental impact of desalination, a process for obtaining drinking water from seawater, is even more dramatic. 16,000 units are active worldwide producing 95 million cubic meters of drinking water per day.
But to produce this indispensable water in many parts of the world, 142 million cubic meters of brine are produced. This substance, loaded with salt and chemicals, is released into the sea or into evaporation ponds.
It is the Persian Gulf countries that are the most dependent on this technology, and they alone reject 55% of the global brine. And these discharges have a strong ecological impact in the seas where they are rejected.
Biodiesel, batteries of electric cars are also technologies that scientists hope to further improve the environmental impact in the coming years. So that these green technologies remain so.