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The use of renewable energy, notably solar and wind energy, has grown exponentially in Brazil. Consumers can generate their energy using renewable sources, whether interconnected to the distribution system (on-grid) or not (off-grid). In this paper, a fuzzy method is developed for the recommendation of solar and wind sources, for any location in the Brazilian territory. In many aspects, it can be viewed as a representation of human decision-making using sets and inference rules and also can be with vagueness and uncertainty, being very useful to idealize recommendation systems. Georeferenced and historical data were obtained from 2003 to 2019 on solar irradiation and wind speed, and electricity consumption until 2021. With the energy generation data from photovoltaic panels and wind turbines, this method allows us to propose installed areas by each technology and obtain the membership of fuzzy recommendation between solar, wind, both solar and wind, unfeasible or hybrid. In addition, a long short-term memory neural network and the seasonal autoregressive integrated moving average model were used to predict consumption for more than 30 months ahead, allowing the recalculation of fuzzy memberships and updating the installation area by respective technologies. As a result, the recommendation is given as the installed area (m2) of each technology per km2 of consumer units, as a function of the regional consumption density (MWh/km2). It can be concluded that it is possible to plan the viability of the type of renewable energy used, according to regional characteristics for smaller consumer units (farms, cooperatives, industries, consortiums), given the diversity of these factors in the huge Brazilian territory. This methodology is in line with the Brazilian Normative Resolution that authorizes the generation of energy by landowners. [ABSTRACT FROM AUTHOR]

The world is moving towards a low-carbon economy through renewable energy sources. In this context, concentrating solar power (CSP) technologies can exploit the rich solar resource in Brazil, diversifying the national electricity mix. The aim of this paper is to support the insertion of CSP generation in the Brazilian bottom-up model MATRIZ by analyzing the environmental performance of three CSP technologies: (i) solar tower power (STP) with a thermal storage system (TSS) of 7.5 h; (ii) solar thermal parabolic trough (STPT) with a TSS of 6 h; and (iii) STPT without TSS. From a life cycle perspective, their freshwater consumption and greenhouse gas (GHG) emissions are addressed by employing the software SimaPro, the Ecoinvent database, and the ReCiPe 2016 method, as well as information from the system advisory model (SAM) and the literature. As a result, STP is the most environmentally sound CSP alternative, presenting lower GHG emissions and water consumption than the two STPT technologies. In general, CSP generation proves to be more environmentally attractive than some fossil-fired power plants and renewable energy sources. Moreover, moving the manufacturing of CSP technologies to Brazil has the potential to reduce GHG emissions from the upstream processes of their value chain. [ABSTRACT FROM AUTHOR]

Brazil has great potential for diversification and decarbonization of its energy matrix, with the insertion of a clean and renewable energy source such as hydrogen. This paper seeks to evaluate the surplus energy potential of solar and nuclear plants installed in the country for the production of green and purple hydrogen using high and low temperature electrolysis methods. Based on official reports and databases of energy production and demand, the results indicated that the total potential of surplus solar energy is equal to 4.29E+07 (kWh.d−1). Further, the total potential of electricity production from the hydrogen obtained through surplus solar energy was equivalent to1.87E+07 (kWh.d−1); and the total cost of producing solar hydrogen is equal to 1.07E+03 (USD.kWh−1). In conclusion, the study contributed to demonstrate the pathways to the establishment of strategies that assist the transition to a hydrogen economy in Brazil. [Display omitted] • Surplus energy potential of solar and nuclear plants for green and purple hydrogen production. • Potential of surplus solar energy is equal to 4.29E+07 kWh.d−1. • Electricity production equal to.87E+07 kWh.d−1. [ABSTRACT FROM AUTHOR]

• A new Angle Difference Controller to adapt the power order of embedded HVDC links. • Simulations with the proposed ADC in the official Brazilian Power System model. • Performance comparison of the ADC implemented in LCC HVDC link and VSC HVDC link. • A tutorial example to make it clear the appearance of loop flows in AC-DC systems. This paper discusses the power flow control of embedded HVDC links in the Brazilian grid, with special attention to the requirements of intermittent energy sources where frequent load changes are needed, including power reversal, and automated action is called for. Recently two North-South bipoles, 4000 MW each, ±800 kV, have entered into service, these being embedded in the grid and with separate receiving end converter stations. In this case "reverse" power flow is foreseen, but only on a seasonal basis when water flow is low at the North region. The increasing capacity in wind and solar energy, especially in the Northeast region and the possibility of a new embedded HVDC link to carry the surplus power from this region, call for an adaptable power setpoint in the DC links in order to avoid adverse effects as loop flows and increased losses. The paper investigates the use of angle difference control and proposes a new controller to mitigate those adverse effects. [ABSTRACT FROM AUTHOR]