Distributed Generation in Costa Rica: how do regulation changes move the numbers in the residential sector?

Costa Rica has undergone significant changes in regulations related to distributed generation (DG), particularly regarding photovoltaic (PV) systems. In 2022, a new law was approved, including the possibility for energy consumers and producers (prosumers) to sell excess energy to utility companies, which was not previously allowed. While the law aims to promote and regulate distributed generation, there is growing concern among prosumers and installers that the new regulation is less financially advantageous compared to the previous one. This paper quantifies the financial impact of these regulatory changes on prosumers, using modeled and field–measured residential energy loads to provide a practical comparison. Specifically, two residential scenarios were modeled: one with a typical average monthly consumption of 250 kWh and another with a field– measured 464 kWh. The financial outcomes, including annual savings and payback periods, were analyzed under old and new regulations. Our results demonstrate that while the new law permits energy sales, it results in less favorable economic outcomes for prosumers, raising critical questions about the effectiveness of this policy shift. The findings suggest regulatory updates are necessary to fulfill the regulation’s initial objectives.