Material and Energy Recovery from the Final Disposal of Organic Waste

While receiving nearly 10,000 times the energy that we presently need from the Sun, almost 600 EJ/a, developed and developing countries continue to mostly use fossil fuels even though the technologies available and the adaptation of individual and collective behaviours could make it possible to use only solar energy [...]

While receiving nearly 10,000 times the energy that we presently need from the Sun, almost 600 EJ/a, developed and developing countries continue to mostly use fossil fuels even though the technologies available and the adaptation of individual and collective behaviours could make it possible to use only solar energy.
For example: in developed countries, the drinking water consumption has exceeded 0.2 m 3 per capita per day, even in arid areas where it is produced using a large amount of fossil-based energy; the consumption of fossil-derived fuels for automotive industries reached a level that was unimaginable until a few decades ago; food is produced and marketed, throwing half of the raw material. Additionally, it is absurdly packaged and consumed for a share that does not exceed 50% after keeping in the refrigerator, without any concern for the energy consumption.
All this and much more are part of a long list of irrational and unnatural behaviours and habits.
Each year, the solar energy accumulated as biomass is eight times greater than the current global energy consumption. Still, few appreciate this gift that nature continues to give us. Most of this precious and energy-intensive material is just discharged into the environment or landfilled as waste, thus losing its GHG emission neutral energetic content and the possibility of its mining for producing a variety of precious and renewable compounds.
Waste-to-energy can potentially contribute about 5% to energetic global consumption, and this is not such an enormous contribution; it would be better to avoid or reduce the production of waste drastically. However, some constraints, such as urbanization, make this impossible. Furthermore, the irreversible habits typical of modern living does not allow this. However, we have a moral duty to use the best technologies and strategies to value biomass waste.
We suggested that this Special Issue should meet this moral duty and received ten exciting contributions. Operational Parameters of Biogas Plants: A Review and Evaluation Study [9].

Pilot-Scale Experiences with Aerobic Treatment and Chemical Processes of Industrial
Wastewaters from Electronics and Semiconductor Industry [10].
As can be seen from the titles of the papers, many problems have been addressed, and different technologies were critically evaluated to successfully afford the final disposal and valorization of a variety of waste biomass.
We have worked through the pandemic crisis with incredible difficulty: inaccessible research laboratories, complicated relationships, and very low morale. Nevertheless, we are happy with this work and this example. We extend thanks to all authors from different countries (Romania, Russia, Ukraine, Poland, Germany, Jordan, and Italy) with different degrees of development and problems and aims.
The involvement of many universities, national academies of sciences, and research centers give this Special Issue the unique value that comes from combining different experiences and ways of affording success and solving complex problems.
We hope that everyone will share the desire to name this Special Issue of Energies after Ida, a brilliant young colleague. She contributed to this work but failed to overcome a dark evil and gracefully walked away.
Funding: This research received no external funding.