In the field of renewable energies, there are other renewable technologies in the development phase. Cellulosic ethanol, geothermal energy from hot and dry rock and marine energy are technologies that can complement traditional photovoltaic solar energy, wind energy or hydropower, for example.
However, these technologies are not yet sufficiently developed or have limited commercialization. Many of these new sources of renewable energy have great potential, but they still have a long way to go in research and development.
There are numerous organizations within the academic and commercial sectors that carry out large-scale advanced research in the field of renewable energy. This research covers several areas of focus across the renewable energy spectrum. Most of the research is aimed at improving energy efficiency and increasing overall energy efficiency.
Improved geothermal system.
Improved geothermal systems are related to geothermal energy. These systems do not require natural convective hydrothermal resources. The vast majority of geothermal energy is found in dry and non-porous rock. These geothermal technologies improve and / or create geothermal resources in this "dry and hot rock" through hydraulic stimulation.
It is expected that improved geothermal energy technologies, such as hydrothermal geothermal energy, are basic load resources that can produce energy 24 hours a day as a fossil energy plant.
This renewable energy technology can be used anywhere in the world, depending on the economic limits of the depth of drilling. The good locations are on deep granite covered by a thick layer (3 to 5 km) of insulating sediments that retard heat loss.
Floating solar panels
Floating solar panels is a variant of solar energy. These panels are photovoltaic systems that float on the surface of drinking water reservoirs, quarry lakes, irrigation canals or remediation ponds and tailings. There are a small number of such systems in France, India, Japan, South Korea, the United Kingdom, Singapore and the United States.
It is said that the systems have advantages over the photovoltaic on land. The cost of land is more expensive, and there are fewer rules and regulations for structures built on bodies of water that are not used for recreation. Unlike most terrestrial solar plants, floating matrices can be discrete because they are hidden from public view. They achieve greater efficiencies than photovoltaic panels on land, because water cools the panels.
The photovoltaic panels have a special coating to avoid oxidation or corrosion. Floating photovoltaic installations at utility scale begin to be built. Saltwater resistant floating farms are also being built for use in the ocean. The largest floatovoltaic project so far announced is a 350 MW power plant in the Amazon region of Brazil.
Solar power tower
The solar power tower is a renewable energy power plant to generate electricity from thermal solar energy at low temperature. Solar radiation heats the air under a very wide roofed collector structure similar to a greenhouse surrounding the central base of a very tall chimney tower. The resulting convection causes an upward current of hot air in the tower due to the effect of the chimney. This airflow drives the wind turbines placed in the rising current of the chimney or around the base of the chimney to produce electricity.
Plans for expanded versions of demonstration models will allow for the generation of significant energy and may allow the development of other applications, such as water extraction or distillation, and agriculture or horticulture.
Marine energy (also known as ocean energy) refers to the energy transported by waves, tides, salinity and differences in ocean temperature. The movement of water in the world's oceans creates a vast reservoir of kinetic energy or energy in motion. This energy can be used to generate electricity to power homes, transport and industries. In a certain sense, this renewable source can be considered a variant of hydraulic energy.
The term marine energy encompasses both wave power (surface wave power and tidal power) obtained from the kinetic energy of large bodies of water in motion. Reverse Electrodiálisis (RED) is a technology to generate electricity by mixing fresh river water and sea saltwater in large power cells designed for this purpose; as of 2016 it is being tested on a small scale (50 kW).
The oceans have a huge amount of energy and are close to many, if not the most concentrated populations. Ocean energy has the potential to provide a substantial amount of new renewable energy worldwide.
Offshore wind energy is not a form of marine energy, since wind energy is derived from wind, even if wind turbines are placed on water.
Experimental solar energy
Concentrated photovoltaic systems use concentrated sunlight on photovoltaic surfaces for the purpose of generating electricity. Thermoelectric or thermovoltaic devices convert a temperature difference between different materials into an electric current.
This renewable energy technique is based on the processing of biomass to convert it into ethanol and the production of certain enzymes. There are several refineries that can process biomass and turn it into ethanol, while other companies produce enzymes that could allow their future commercialization.
The change from raw materials for food crops to residues of native residues and pastures offers significant opportunities for a variety of actors, from farmers to biotechnology companies, and from project developers to investors.
Solar heat pump
A heat pump is a device that provides thermal energy from a heat source to a heat sink. Heat pumps are designed to move thermal energy in the opposite direction to the direction of spontaneous heat flow by absorbing heat from a cold space and releasing it to a warmer one. To carry out this thermodynamic process, an external energy contribution is required since, on the contrary, it would not comply with the laws of thermodynamics.
A solar-assisted heat pump represents the integration of a heat pump and thermal solar panels into a single integrated system. Normally, these two technologies are used separately (or only placed in parallel) to produce hot water. In this system, the solar thermal panel performs the function of the heat source at low temperature and the heat produced is used to feed the evaporator of the heat pump. The objective of this system is to obtain a high COP and then produce renewable energy in a more efficient and less expensive way.
It is possible to use any type of solar thermal panel (sheets and tubes, roll-bond, heat pipe, thermal plates) or hybrid (mono / polycrystalline, thin film) in combination with the heat pump. The use of a hybrid panel is preferable because it allows to cover a part of the electricity demand of the heat pump and reduce the energy consumption and, consequently, the variable costs of the system.
A new form of renewable energy is algae fuels.
The production of liquid fuels from varieties rich in algae oil is a subject of ongoing research. Several microalgae cultivated in open or closed systems are being tested, including some system that can be set up in abandoned industrial areas and in desert areas.
In 2016, Solar Impulse 2 was the first solar powered aircraft to complete a circumnavigation of the world.
An electric plane is an airplane that runs on electric motors instead of internal combustion engines, with electricity coming from fuel cells, photovoltaic cells, ultracapacitors, radiant power, or batteries.
Currently, the manned electric planes that fly are mostly experimental demonstrators, although many small unmanned aerial vehicles operate on batteries.
Artificial photosynthesis uses techniques that include nanotechnology to store solar electromagnetic energy in chemical bonds by splitting water to produce hydrogen and then using carbon dioxide to produce methanol.
Researchers in this field strive to design molecular imitators of photosynthesis that use a wider region of the solar spectrum, employing catalytic systems made of abundant and economical materials that are robust, easily repaired, non-toxic, stable in a variety of conditions. environmental and performance are more efficient, which allows a greater proportion of photon energy ends up in the storage compounds, ie carbohydrates (instead of building and maintaining living cells).
Solar energy based on space
This form of use of solar energy has the disadvantage of the difficulty of transporting the electricity generated to the Earth.