The State of Solar Energy Resource Assessment in Costa Rica
Abstract
It is traditionally assumed in Costa Rica that given its geographical location there must be a large potential for electricity generation from solar energy. However, this potential has not been properly assessed with measurements of high quality up to modern standards, and therefore the country still lacks the information needed to either establish public policies to promote solar energy utilization or support the development of commercial projects. The current trend of increasing energy consumption in the country and the existing interest on increasing solar energy utilization require an updated analysis of the available solar resource in order to generate meaningful data that can be used by government and private parties. Costa Rica has been measuring global horizontal irradiation for over 20 years in several stations distributed throughout the country, although in most cases the measurements have been conducted without quality control checks and postprocessing. This network of radiometric measurement stations was set out to identify regions with adequate levels of average daily sunlight in order to define regions in which solar energy systems could find engineering applications. Currently the measurement network is operated for the ICE group (Costa Rican Institute of Electricity), and consists of Second Class Pyranometers CHP3 and First Class Normal Incidence Pyrheliometer CHP1, both from Kipp and Zonen brand. The information is stored as minute-averages and spans a period of four years. No locally developed and validated satellite estimation models have yet been reported, and instead the country relies on commercial data. There are no measurements of either diffuse or direct normal irradiance. A more complete climatological characterization of the solar resource is possible by using the measured data of global horizontal irradiance coupled with the existing diffuse fraction models such as (Boland, Lauret, & Ridley, 2010) and (Jing, Boland, & Ridley, 2012), which allow decomposing the Global horizontal into its direct and diffuse components. This represents a significant improvement in the amount and quality of solar information that is available for solar engineering applications in Costa Rica and can be published for public access.
Keywords
Solar data, Irradiance, Radiation, Solar energy, Resource assessment & climate, Solar potential, Central america