The common sense of sustainability is to prioritize the reduction, reuse and recycling of waste, but ultimately envisages its value as a valid option to avoid ending up in a landfill.
The process of using waste to produce energy is called recovery, which is nothing more than obtaining energy from waste that can not be separated and is not recyclable. These are transferred to biomethanization plants where they are transformed into biogas or burned to produce energy.
For example, in the case of plastics, do not forget that they are made mostly of oil, so when burned, “generate as much heat as natural gas or diesel, and can be used to produce electricity and heat”, point out from the Energy Foundation of the Community of Madrid.
To give you an idea, of the two million tons of plastic waste of domestic origin that are produced annually in Spain, about 14% is used to generate energy. And is that “the combustion of a ton of plastic bottles generates as much energy as burning 1.4 tons of coal,” says Fenercom.
The same sources assure that only with the plastic film that arrives at the landfills could be obtained more than 185 million liters of diesel recovered per year, enough to supply heating to some 50,000 homes.
This process is also part of the concept of “circular economy” that tries to make the most of all the resources we put into circulation instead of using new ones, a bad habit that destroys the planet’s biodiversity.
In the case of organic waste, which accounts for almost half of the total weight of garbage that we generate in our homes, it can be burned in incineration plants and produce electricity or also be used to produce bioethanol and biodiesel, and use them in place of the gasoline and diesel. This last option is more efficient because when retaining a lot of humidity they do not generate much heat when they burn, explain the same sources. Every 10 kilograms of organic waste we can obtain up to 500 cubic meters of biogas.
Likewise, organic waste is used to obtain biogas, which is as good as fuel for transport as for heating or electricity. One cubic meter of biogas equals 0.6 cubic meters of natural gas, and for every ton of waste, up to 500 cubic meters of biogas can be produced.
The point is that if the biogas that is generated in the landfills is not captured and used -this is done in about 34 of the 183 landfills we have in Spain- it ends up being burned or allowed to escape into the atmosphere, with what this means in emissions of greenhouse gases, the main cause of global warming.
In any case, remember that the most important thing is to respect the “Rule of Three Rises: reduce, reuse and recycle”, in this order, since when we apply it we recover much more energy than we get when we use waste as energy. For example, making paper from a used one requires 65% less energy, and so with everything…