Power-system-wide analysis of the benefits of reserve provision from solar photovoltaics in South Africa

Abstract

Reserve provision from standalone solar photovoltaic (PV) power plants has to date not been adopted in practice but has been conceptualised by a number of authors for variable renewable energy (RE) power plants like solar PV and wind. The authors have assessed the economic viability of this application in a developing country with low-levels of solar PV penetration thusfar (South Africa). The majority of power generation in South Africa is coal-fired, making up over 70% of the installed capacity. However, South Africa has abundant solar resources and has seen a dramatic decline in solar PV tariffs over the past few years. The value of reserve provision to the system from solar PV was determined by simulating the South African power system on an hourly basis in a least-cost unit commitment and dispatch model capable of co-optimising energy and reserves simultaneously. Preliminary results showed that purely reserve provision in the short term by new solar PV in South Africa is not yet economically viable as it requires a solar PV LCOE below 285 ZAR/MWh which is not likely to materialise in the short term.. However, results showed that a combination of reserve provision and energy generation by new solar PV capacity could be economically viable in the short term at solar PV LCOE below 430 ZAR/MWh. This research work is ongoing and will be expanded to include aspects of solar PV forecasting, investigations into the provision of other reserve types by solar PV simultaneously, reserve provision by other Renewable Energy (RE) technologies as well as further research into possible reserve costing and incentivisation.