The search for alternatives to traditional sources of electric energy opens the way for a new market in the world, and for Brazil in particular. Still in its first steps, but with immense potential, the generation of energy from solar irradiation and hydroelectric plants in hybrid systems is an important alternative. On the other hand, single source power systems, when designed to meet a particular demand without fail, lead to low market acceptance due to the availability of resources and low efficiency in performance that rewards high initial investment costs. One solution to balance and optimize energy supply is the use of more than one energy resource when sources can be complementary. Among several possible combinations reported in several studies, the hybrid photovoltaic hydroelectric system is considered to be an optimal and interesting combination. In this context, the present article makes a technical and economic pre-feasibility analysis of a hydroelectric photovoltaic hybrid system, operating photovoltaic panels on floating structures on the water surface to allow the use of the Laranjeiras dam. The study was conducted based on simulations with HOMER. The solution indicated as optimal was the installation of a hybrid energy system, implementing a hydroelectric power plant at the base of the dam, with 1497 kW of installed capacity, operating simultaneously with a set of photovoltaic modules, on the water surface of the dam, with 180 kW of installed capacity, and a power limit for the purchase and sale to the grid equal to 400 kW, to supply the demand of consumer loads up to 40 MWh per day. This combination would result in an initial cost of US$3984.885 per kW and an energy cost of US$0.026 per kWh.

In recent years, renewable resources have become an important alternative to increase the capacity of power generation. Among the resources available, the energy in the oceans have attracted more interest and experiencing a period of strong development. Wave energy is the one that is currently closest to reach a stage of technical and economic maturity. In this process, computational tools to facilitate evaluation of the feasibility of power systems including ocean wave power plants are critical. This paper presents the use of software Homer, version Legacy, for evaluation of technical and economic feasibility of hybrid energy systems including contribution of wave energy. Homer is a software designed for the optimization of micro power systems that has a very broad spectrum of applications. A case study in southern Brazil is presented, studying the inclusion of an ocean wave power plant in a wind biodiesel hybrid system and showing the functionality of Homer for this purpose.

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The use of renewable resources for power supply in family homes has passed the stage of utopia to became a reality, with limits set by technical and economic parameters. This paper presents the results of a project originated from the initiative of a middle-class family to achieve energy independence at home. The starting point was the concept of home with “zero energy” in which the total energy available is equal to the energy consumed. The solution devised to meet the energy demand of the residence in question is a PV wind diesel hybrid system connected to the grid, with the possibility of energy storage in batteries and in the form of heating water and the environment of the house. As a restriction, the family requested that the system would represent little impact to the lifestyle and landscape. This paper aims to assess the consequences of reductions in the cost of the PV modules on the optimization space, as conceived by the software Homer. The results show that for this system, a 50% reduction in the cost of PV modules allows all viable solutions including PV modules.

The oceans can provide us with several direct sources of renewable energy, such as wave energy, energy from currents and energy in thermal gradients among other energy resources. The uses of these resources have not yet reached technical and economic maturity, but they have experienced significant advances in recent years. In this process, tools for feasibility analysis of hybrid systems including specific power plants are important. This article is dedicated to the feasibility study of hybrid systems containing power plants based on the energy of ocean and tidal currents. The software currently available for feasibility studies do not present specific models already developed for the simulation of this kind of power plants. Thus, this technical note shows how Homer software (Legacy version) can be used to conduct this type of study in pre-feasibility level. This article also presents a case study in which Homer is applied, focused only on Homer adaptation but without exhausting the subject, showing a feasibility window that would include current power plants with certain cost and efficiency in an existing PV wind biodiesel hybrid system.