Isolated systems are those places not connected to the national grid, for technical or economic reasons and supplied by local generation. Nowadays in Brazil, there are about 250 isolated systems, concentrated in the Northern region, which sums only 1 percent of the electricity total consumption of the country, but represents around 40 percent of the territory. Most of these systems are supplied by diesel power plants, with a few examples of generation by natural gas, biomass or small-hydro. Historically, the diesel gensets have been an easy solution, due to its facility to build, operate and maintain. Also, these power plants do not require complex projects and large areas and have relatively low investment cost associated. Despite the complex logistics of fuel supply, mostly done by boats along Amazonian rivers, the energy generation has worked quite well in the last decades. However, the operational costs, especially those related to the fuel, are very high. In some places, depending on the season and navigability, it can reach R$ 10/liter (around US$ 3/l), resulting in high generation costs, that can achieve R$ 1,600/MWh (around US$ 450/MWh). All electricity consumers in Brazil share a great part of this cost. Other problems related to the diesel-based generation are the pollutant and greenhouse gases emissions, in the middle of the Amazon forest, where most of the isolated systems are located. Some effort has been made to connect isolated systems to the national grid, reducing the local generation, and consequently, its costs and emissions. However, the expansion of conventional power grid has high costs and, in some cases, technical and environmental constraints (Ribeiro, et al., 2012).