Popis: |
Despite all efforts, there is currently no sustainable city in the world. In some cities there are positive changes towards sustainability (RES instead of fossil fuels, using electric cars, waste recycling, reduction of CO2 emissions, etc.), but in order to achieve the sustainability of the Earth as a planet, all cities in the world should be made sustainable, as they account for about 80% of total energy consumption. This means that future sustainable cities will be able to produce all the necessary energy and drinking water using the RES system, applying pump storage hydroelectric (which technology can balance seasonal surpluses and shortages of solar energy), as well as applying seasonal heat storage technologies. On the other hand, despite the efforts of the signatories of the Paris Agreement, it is questionable whether these objectives can be achieved at all due to political, economic and other obstacles. In addition, current EU policy might even take a step backward by trying to introduce a green label for nuclear energy and natural gas (European Commission taxonomy proposal), which calls into question the implementation of The European Green Deal by 2050. Recognizing the importance of this historic moment in stopping climate change, the paper presents a way to address the sustainability of cities in the world, proposing a systematic approach to this problem, taking into account the most relevant criteria: size, climate and natural disasters. Considering that about 50% of the world's population lives within the area 20˚ N and 40˚ N and that over 30% of the population lives in cities with less than a million inhabitants ; but also the fact that cities outside this geographical area may also have relatively large amounts of direct solar radiation ; the cities of Zagreb and Copenhagen (which cities have practically the same amounts of direct solar radiation) were selected as case studies, for which original solutions for achieving overall sustainability were given. In doing so, Seawater Steam Engine (SSE) technology, which uses renewable energy for simultaneous energy and drinking water production, is presented, as well as original strategies for solving the problem of accommodating SSE collectors in cities (with canopies), but also the original concept of energy and drinking water distribution (with loops). However, just as SSE technology is basically open source technology that can use other renewable energy sources, it also means that it could make other cities in the world up to a million inhabitants without enough solar energy completely sustainable, whereby other RES would be used. In addition, the paper presents strategies for resolving cities with more than a million inhabitants all the way to the metropolis. This paper also introduces the next generation of RES technologies, whose originality lies in the fact that, in the future, they can simultaneously produce energy and drinking water which is fully consistent with the new “Philosophy of Sustainability”. With this concept, the cities in the world could become the “basic building blocks” that would "build" the overall sustainability of the Earth. |