An Analytical Approach for Determining the Appropriate Medium Voltage (MV) Cabling Level in Renewable Energy Parks

Renewable energy parks, primarily solar parks and wind farms are connected to the high voltage PCC by medium voltage (MV) cabling system. Cabling system can have significant impact on CAPEX of renewable park. On the other hand, during exploitation power losses can have significant impact on hidden costs of energy park operation (OPEX). CAPEX and OPEX including hidden costs can contribute to unnecessary costs. MV cabling system in renewable energy parks is specific in terms of MV level. This paper gives an analytical approach for determining the appropriate MV cabling level in renewable energy parks. Voltage levels 20 kV, 30 kV, 33 kV and 35 kV were examined. For each voltage level constraints in terms of voltage drop are given and the minimum cable cross-sections is calculated. Calculations of short-circuit levels and power losses have been made for examined voltage levels. Appropriate MV cable level is voltage level with the minimum costs in 20 years exploitation of MV cable system. Mentioned costs are sum of MV cable system costs (CAPEX) and power losses costs in exploitation period.