Abstract: This research compares the building energy consumption and the photovoltaic economic analysis between residential buildings in Santiago de Chile and Santo Domingo of the Dominican Republic. The methodology considered thermal simulation, sizing of a solar PV system, an economic analysis and CO2 emissions given the solar resources of both countries. A scenario where the constructive systems are switched between the countries was also analyzed. A comparison of the energy performances of the houses exposed to other climate conditions. Results show that housing in Santiago de Chile required less energy than housing in Santo Domingo due to the fact that the thermal transmittance of the enclosures of the Chilean housing has better thermal behavior, compared to the materials of the Dominican housing. Dominican houses need a higher amount of electricity for air cooling due to the high temperatures in the tropic. Meanwhile, Chilean countries requires a higher amount of gas for heating purposes. The Dominican Republic lacks thermal regulation for construction material, and applying Chilean standards in Dominican houses, helped to lower the yearly electricity demand by 19%. Dominican constructions materials improvement could have an important impact in the country's overall goal to lower CO2 emission and in-house energy savings. The economic analysis showed that the Dominican Republic renewable energies incentives contribute to the development of very attractive PV projects, meanwhile in Chile, the use of net metering instead of net billing could increase by 11 times the net present value of PV projects.