A 'feasibility space' as a goal to be achieved in the development of new technologies for converting renewable energies.

This method article proposes the establishment of a feasibility space as an objective to be achieved during the development of new technologies to convert energy from renewable resources. The feasibility space can also be a reference when designing an energy system based on renewable resources. The feasibility space is a set of parameter values for the design stage that define the economic and technical feasibility of an energy system or a new technology, which must be satisfied when the energy system comes into operation or when the new technology for converting power goes into operation.

Spatial representation of temporal complementarity between three variable energy sources using correlation coefficients and compromise programming.

Renewable energy sources have shown remarkable growth in recent times in terms of their contribution to sustainable societies. However, integrating them into the national power grids is usually hindered because of their weather-dependent nature and variability. The combination of different sources to profit from their beneficial complementarity has often been proposed as a partial solution to overcome these issues.

Simulating hybrid energy systems based on complementary renewable resources.

The complementarity between energy resources can influence the performance of hybrid generation and storage systems, and can also decisively influence their design. Renewable resources may have intermittent characteristics that make the study of the influence of complementarity on the performance of hybrid systems quite difficult. The establishment of a performance limit of hybrid systems based on renewable resources and the study of the effects of complementarity considering this limit can provide interesting results.

Simplified evaluation of energetic complementarity based on monthly average data.

Energetic complementarity is a subject that has been holding more and more attention from researchers in recent years, being a concept that can be applied both in energy planning stages and in phases of operation of energy systems based on renewable energy resources. The complementarity between two renewable sources of energy has three components: time-complementarity, energy-complementarity and amplitude-complementarity, and can be determined between raw energy availabilities or between energy generated by power plants. Complementarity can be evaluated between two renewable resources in the same place or between two renewable resources in different places and these two types can be denominated respectively as temporal and spatial complementarity.

Qualitative evaluation of spatial complementarity between renewable energy resources with complementarity roses.

Energetic complementarity is a subject that has been concentrating more and more attention of the researchers around the world in the last years, a concept that can be applied both in energy planning and in operation of energy systems based on renewable energy resources. Spatial complementarity is the energetic complementarity evaluated between two renewable resources in different locations and, as well as the complementarity evaluated between resources in the same location, has three components: time-complementarity, energy-complementarity and amplitude-complementarity. At the same site, however, complementarity assessment can involve multiple resources simultaneously, and the study of these circumstances requires appropriate tools to handle such information.

Energy at the Junction of the Rivers Negro and Solimões, Contributors of the Amazon River, in the Brazilian Amazon.

The Negro and Solimoes rivers join in front of the Brazilian city of Manaus to form the Amazon River. This "meeting of the waters" is a natural phenomenon of great aesthetic beauty that has been the focus of attention of researchers all over the world in various scientific fields. The waters of the Negro are darker and warmer, while the waters of the Solimoes are lighter and cooler.