By considering technical, economic, and socio-environmental criteria, in addition to the natural resources of each location, the assessment of wind and photovoltaic generation potential provides an opportunity for the conception, adaptation, and improvement of methods and models, preventing severe compromises to the realism of problem solutions regarding: i) the siting of a new hybrid energy generation power plant, and ii) the sizing of the power plant and its connection to the grid. The proposal is to integrate these problems into a model that preserves their nature, allowing them to be solved by distinct methods that are best suited to each. The sizing and connection problem is a mixed-integer optimization problem to be solved by MILP. A metaheuristic is applied to solve the siting subproblem and process the optimization as a whole. The Differential Evolution metaheuristic was tested to validate the model and applied to a real-world case study for prospecting renewable energy sources (RES) to be harnessed with an optimal return on investment. In practice, the proposal allows for a much more realistic model of the problem by considering, for example, the connection costs of the new power plants. The results found herein confirm the viability of the proposal.