Renewable Energy Source

Global and regional trends indicate that energy demand will soon be covered by a widespread deployment of renewable energy sources. However, the weather and climate driven energy sources are characterized by a significant spatial and temporal variability. One of the commonly mentioned solutions to overcome the mismatch between demand and supply provided by renewable generation is a hybridization of two or more energy sources into a single power station (like wind-solar, solar-hydro or solar-wind-hydro).
In the last decades, energy scarcity has become an important issue globally. Renewable energy sources have gained importance due to limited fossil fuel reserves and increased concerns on climate change. In this regard, municipal wastewater is a remarkable energy source since huge amounts of wastewater are generated and treated all over the world every day. Conventional activated sludge (CAS) process, which has been in use for more than a century, is the most widely applied treatment method for municipal wastewater.
In the last decades, energy scarcity has become an important issue globally. Renewable energy sources have gained importance due to limited fossil fuel reserves and increased concerns on climate change. In this regard, municipal wastewater is a remarkable energy source since huge amounts of wastewater are generated and treated all over the world every day. Conventional activated sludge (CAS) process, which has been in use for more than a century, is the most widely applied treatment method for municipal wastewater.
Global anthropogenic activities resulting in the emission of harmful greenhouse gases (GHGs) to the atmosphere have increased the challenges faced from climate change. The greater awareness of the need to mitigate climate variability has brought about intense focus on the adverse impacts of fossil-fuel based energy on the environment. Being the single largest source of carbon emissions, energy supply has attracted much attention and more so that, climate change impacts extend beyond national boundaries.
Elsevier, Renewable and Sustainable Energy Reviews, Volume 71, 2017
In this paper, five most emerging renewable energy sources are analyzed. These emerging renewables are either special or advanced forms of the mainstream energy sources (solar, wind, geothermal, biofuels, biomass, and hydro) or brand new technologies. The five emerging renewable technologies discussed in this paper include marine energy, concentrated solar photovoltaics (CSP), enhanced geothermal energy (EGE), cellulosic ethanol, and artificial photosynthesis. Marine energy is divided into wave energy, tidal energy, tidal/ocean currents, salinity gradient, and ocean thermal energy conversion.