Investigating the operations and maintenance strategy of solar photovoltaic plants in South Africa

Abstract

The REIPPPP (Renewable Energy Independent Power Producer Procurement Program) was introduced in South Africa (SA) in August 2011. By the end of 2014 more than 1000 MW was allocated to solar photovoltaic (PV) plants (Milazi & Bischof-Niemz, 2015). In Bid Windows 1, 2, 3 and 4, 45 solar PV projects were part of South Africa's REIPPPP (Department of Energy, 2014). The engineering and construction of utility scale solar PV plants was led by foreign companies since SA has never owned or operated a utility scale solar PV plant previously. The amount of installed PV globally has increased tremendously since 2010. In September 2013 the first solar PV IPP (Independent Power Producer) was synchronised onto the South African national electricity grid. Therefore, operation and maintenance (O&M) of solar PV plants is a relatively new area for owners of PV plants. Naturally, owners of solar PV plants will want to maximise energy yield of the plant, and this is only possible by having a skilled maintenance team which follow a maintenance strategy. Solar PV plants are not maintenance free, resulting in fulltime staff performing corrective and preventative maintenance in utility scale PV plants. In this research study a review of current practices of solar O&M world-wide and in SA is discussed. Recommendations are provided to owners and O&M managers of solar PV plants on issues such as staffing requirements based on DC (Direct Current) capacity, module cleaning strategies and O&M contracts. The research findings indicated that on average 1% of total modules installed are kept as replacement parts and two central inverters are kept as spare parts. Cracked glass, snail tracks and hot spots were the three most common PV module faults. The most common faults in the PV plant were related to communication networks and inverters.