Among the major challenges for the power systems of the future, one mayfind the arise of a new approach of electricity production - the Distributed Generation (DG) systems - and photovoltaics (PV) is the main technology for this new approach. In this scenario, a new electricity market agent appeared - the prosumer - consumers that can also produce their own energy. The retail price is one of the main factors that encourages PV systems adoption under a net metering scheme. The present work shows an investigation on the influence of regulated electricity tariffs as volumetric charges structure on the residential DG PV systems adoption in a developing country context. I use a panel data from 2013-2017 with 5570 municipalities in Brazil, having as response variable the number of new PV installations and as explanatory variable the electricity tariffs among 105 different distribution companies. The results imply that for each one BRL cent of tariff increase, there will be an expansion of about 5.3% in new residential PV projects in the following year.