Following the global trend, solar photovoltaics (PV) is playing a substantial role in electricity generation in Mauritius as rapidly falling costs have made unsubsidised solar PV-generated electricity cost-competitive with fossil fuels. During the last decade, solar PV marked records every year, with an estimated 25% increase annually reaching the 300 GW mark in 2016. Even in Mauritius, renewable energy promotion mechanisms introduced since 2011 have led to more than 18 MW of PV installed by the end of 2015 with almost 60 MW yet to be connected in the coming years to reach almost 100GW by 2020. But for proper planning of PV systems integration a solar map for Mauritius is crucial. Solar maps help keep track of progress on sustainability goals for the country and will also educate citizens of the possible rewards of using solar power instead of other conventional sources of power. The solar map for Mauritius can be reliably used to help in choosing the appropriate site for PV plants and as well will help financial appraisal of PV projects.
In addition PV system design requires information on daily solar energy, peak levels of solar power as well as information on temperature variations. The latter can only be achieved through high-precision on-site measurements of solar radiation under the local environmental conditions.
Under the UNDP/GEF funded “Removal of Barriers to Solar PV Power Generation in Mauritius, Rodrigues and Outer Islands” project, the Ministry of Energy and Public Utilities (MEPU) and Central Electricity Board (CEB) have requested the services of the University of Mauritius (UoM) for the development of a Solar Map. The objective of this project is to accelerate sustainable on-grid PV electricity generation in Mauritius, Rodrigues and Agalega through the deployment of an online GIS Solar map which is freely accessible to public.
Solar stations have been deployed in 9 sites across Mauritius, 2 Sites in Rodrigues and 1 site in Agalega in order to measure the following quantities: global horizontal irradiance (GHI), plane of array irradiance (PoAI), ambient temperature and cell temperature. These parameters are essential for design, evaluation and financial appraisal of PV systems and projects.
GHI is measured at high frequency sampling rate of one minute using ISO 9060 secondary standard broadband EKO MS 802 pyranometers. MS 802 is widely used as standard reference sensor for PV research and climatology. It has fast response time, temperature compensation over a wide temperature range and high quality optical dome. PoAI is measured using Si-O2-Pt mono-Si reference with integrated cell temperature sensor. Ambient temperature is measured with the aid of temperature sensors. Frequency of measurement will be adjusted to 1 minute. The sensors at each station are connected to a signal conditioning element and a web based data logger that transmit all measured data to a central server located at the University of Mauritius. The data are then processed and used to generate GIS solar maps for Mauritius, Rodrigues and Agalega.
The reference cells are calibrated as per IEC 60904-3 under outdoor conditions. The thermopile pyranometers are calibrated as per ISO 9847 – Calibration of Pyranometer using reference Pyranometer and as per ISO 9846 - Calibration of Pyranometer using pyrheliometer.