Technical design and characterization of a ground based solar metrology network on Reunion Island

Paper presented to the 3rd Southern African Solar Energy Conference, South Africa, 11-13 May, 2015.The roadmap of Reunion Island regarding energy is to reach autonomy by 2030. Obviously, renewable energies will play a key role in this ambitious project. However, a couple of years ago, a limit set by the French government relatively to the amount of lethal power injected on the electrical grid stopped the thrust: at any time, intermittent sources should not exceed 30 % of the whole production. This is due to the fragility of the grid: rugged topography, no interconnection. The University of La Reunion through the LE2P lab (Energy, Electronic and Process) decided to search a solution by predicting the solar resource in order to erase part of the intermittency of the production coming from the solar plants. Along this track, the first step is to evaluate precisely the resource and study its spatio-temporal variability. To do so, the LE2P gets engaged in deploying, at ground level, a network of monitoring stations. These units should be capable to produce field data responding to specific requirements in terms of acquisition frequency and quality, compatible with the clustering tools and mapping programs developed beside. Today, LE2P team manages a fleet of more than 15 stations, with various configurations, all over Reunion Island and plans to extend its network to neighboring territories. This article proposes to present in details the different components of a typical station, how they have been selected and how they are maintained. We will also see how the lab gets organized in order to propose top quality data to the solar scientific community.cf201

Technical design and characterization of a ground based solar metrology network on Reunion Island

Paper presented to the 3rd Southern African Solar Energy Conference, South Africa, 11-13 May, 2015.The roadmap of Reunion Island regarding energy is to reach autonomy by 2030. Obviously, renewable energies will play a key role in this ambitious project. However, a couple of years ago, a limit set by the French government relatively to the amount of lethal power injected on the electrical grid stopped the thrust: at any time, intermittent sources should not exceed 30 % of the whole production. This is due to the fragility of the grid: rugged topography, no interconnection. The University of La Reunion through the LE2P lab (Energy, Electronic and Process) decided to search a solution by predicting the solar resource in order to erase part of the intermittency of the production coming from the solar plants. Along this track, the first step is to evaluate precisely the resource and study its spatio-temporal variability. To do so, the LE2P gets engaged in deploying, at ground level, a network of monitoring stations. These units should be capable to produce field data responding to specific requirements in terms of acquisition frequency and quality, compatible with the clustering tools and mapping programs developed beside. Today, LE2P team manages a fleet of more than 15 stations, with various configurations, all over Reunion Island and plans to extend its network to neighboring territories. This article proposes to present in details the different components of a typical station, how they have been selected and how they are maintained. We will also see how the lab gets organized in order to propose top quality data to the solar scientific community.cf201

Research collaboration in solar radiometry between the University of Reunion Island and the University of Kwazulu-Natal

Paper presented to the 3rd Southern African Solar Energy Conference, South Africa, 11-13 May, 2015.Since 2012, the Universities of KwaZulu-Natal and Reunion Island have collaborated on a joint programme of solar energy research. The initiative has two principle aims: the development of solar forecasting techniques and the expansion of solar monitoring capabilities from continental Africa into the southern Indian Ocean region. In this paper, we introduce the programme and review the progress made. A key activity is performance validation of a low-cost radiometric sensor, the Delta-T Devices SPN1, which has been operated at a UKZN ground station for comparison against reference sensors. The instrument potentially represents an opportunity to expand existing radiometric networks by reducing the cost of ground station facilities. A novel feature of the device is its use of seven thermopile sensors and a stationery shading mask which together enable the simultaneous measurement of global horizontal and diffuse horizontal irradiance. It is important that the instrument performance should first be assessed, however, so that its measurement uncertainty is known ahead of deployment. Data from the UKZN trial are included in the paper, along with a description of a meteorological classification system that may be used in solar forecasting systems. The system is based on the direct solar fraction, that is, the ratio of direct horizontal irradiance to global horizontal irradiance. A clustering methodology is described and sample data are provided to illustrate the ability of the method to segregate days into statistically significant bins.cf201