There is so much talk about green and renewable energy nowadays, but it usually covers the most common ways of alternative energy sources. Many people are unaware of the great diversity of ways to generate energy, but here I bring you some of these. Some of them are quite promising.
Piezoelectricity uses a simple principle of generating energy by applying pressure in certain electromagnetic or piezoelectric materials, like ceramics and crystals, which store the resulting stress as electric charges. This method is nothing new, as it was discovered more than a century ago by Jacques and Pierre Curie, allowing different applications that convert simple mechanical forces to energy. We could also use the pressure from cars on the road and use the generated energy to power the illumination of signs and traffic lights, and according to some tests, we could generate an output of 200KWh from a kilometer of a single line road.
Another example includes the use of disco floor on nightclubs, and sidewalks or staircases on the street, using the pressure of footsteps to generate local energy power, or store it to transfer to other locations. Despite its simplicity and recent gain of popularity, this approach for a renewable source of energy still facing some resistance and low adoption today, despite its low cost and small space required for implementation. In the future, we may discover even cheaper and more efficient ways to operate using this method.
The biomass energy is generated from the organic waste of animals and plants, like trees, crops, landfill waste, and manure. It is a good fit for the replacement of the non-renewable fossil fuels, like coal and gas, as they don’t generate carbon or greenhouse gas during its production. Woods are usually the most common source of biomass fuel, and it is usually clean and easy to replace and recycle.
The use of biomass fuel is still controversial in some environmental aspects since it requires the use of large areas and more deforestation, and the development of the whole process is usually quite expensive. This also includes storage and transportation costs, as well as the usage of crop space for different purposes other than food harvesting. Besides, some biomass products, like the ethanol, are not as efficient as the alternatives, like gasoline.
The storage of nuclear waste has been of great concern to many nations for a long time, which can reach more than 90% from the whole production. The idea behind this procedure is to convert the waste, like uranium and plutonium, through several chemical phases and produce energy back to the power plants. The reuse of waste for nuclear plants would extend its usage and efficiency as a whole, and reduce the lifetime of radioactive materials to just a fraction of it.
Some consider the process of recycling of nuclear fuel very costly and not worth pursuing, and there have been a lot of resistance in the United States on this matter, mostly due to the fear of the production of nuclear weapons from stolen material. But other countries like France and Japan already adopt these renewable measures, generating as much as 80% of the total energy for nuclear power.
The use of the sea movement to generate energy looks really promising. It can be achieved in two ways: (1) harnessing the movement of the ocean tides on seashore areas and convert it to energy through mechanical machinery operation; (2) exploiting the tidal currents, mostly on deep oceans, to spin submerged turbines that will generate and store the energy using the same mechanical principle. As it only depends on the kinetic energy from tides and the influence of gravitational pool on Earth, it is a potential and favorable choice for mass energy production.
If this process becomes easily scalable, it could greatly reduce the power demand problems in both urban and rural areas, and also avoid or reduce drastically the possibility of a global energy shortage in the future. Unfortunately, since the infrastructure is very expensive to build, there are usually a few trade-offs involved, like the tidal waves movement in the location and the distance from storage to usability areas. France is probably the country that makes the most use of this kind of energy source alternative.
Space Solar Power
This approach consists of harvesting solar power from a geostationary array that orbits outside the Earth and transmitting the energy back to it wirelessly through microwaves or lasers. This interesting idea has been available since the beginning of the space era by Isaac Asimov, and in theory seems straight out of a science fiction, but it is far more plausible than it sounds. The directing solar radiation would allow us to capture far more energy from solar panels, and we don’t even have to worry about taking so much space to install the whole structure.
For the alternatives of transferring the energy back to the stations on Earth in order to generate electricity, the laser option is more accurate, but some obstacles may prevent its transmission. Microwaves, on the other hand, can go through solid objects, but may also cause radio interference and affect different sources of communication. This concept may seem too far in the future, but the recent space breakthroughs make it seem far more viable. Japan recently showed some interest in this subject and is already considering a power station orbiting the planet in 10 years.
There is a long way until we find the best choices of sustainable and renewable energy sources. Many factors come into play when we consider the mass adoption of these approaches, like location, availability, and renewability. Hopefully, we will be able to reach this new era of renewable resources before a world crisis emerges.