Wemen Solar Farm

Client: RCR Infrastructure, Laing O’Rourke and WIRSOL Energy
Location: Mildura, Victoria
Date: 2017 - 2018 

Providing electrical design for the construction of the photovoltaic arrays and substation of a new 98 MVA/110 MWp solar farm 

Background

Large-scale solar has a large role to play in supporting Australia’s energy transition from fossil fuels to renewable energy. Development of the Wemen Solar Farm near Mildura in northern Victoria was supported by the Clean Energy Finance Corporation and adds 110 MW of new solar capacity to the National Electricity Market.

The single-axis tracking project of almost 320, 000 panels spans 783 acres, and is owned by global renewable energy group, WIRSOL Energy.

Solution

Entura was engaged by RCR to undertake the detailed design of the photovoltaic (PV) and direct current (DC) equipment and layout for Wemen solar farm.

We undertook the electrical design comprising both the DC and alternating current (AC) components of the solar farm, up to the 132 kV switchyard, including the 33 kV AC collector system, harmonics filter installation design and SCADA interface.

A key component of the project was optimising the DC design elements, including the cabling methods, string grouping configurations and combiner box locations.

During the project, we were tasked with selecting equipment and technology, providing specification for the purchase order (PO) and reviewing equipment specifications provided by vendors. We also developed studies for the electrical design, such as load flow, fault level, arc flash, protection and insulation coordination, earthing and lightening protection and power quality.

In addition, Entura provided detailed design drawings, specifications and reports for PV arrays, primary and secondary electrical designs from power control units (PCUs) until the 132 kV switchyard, including 33 kV switching and control building, 33/132 kV electrical substation and integration of the harmonics filter.

Services provided

  • power system studies and grid connection compliance testing
  • solar DC and balance of plant design
  • secondary protection and control automation
  • AC/DC reticulation design
  • earthing design, inspections and audits
  • insulation coordination design and assessment
  • high voltage substation electrical engineering design, specification, auditing and support
  • harmonic filter installation design

Outcome

Construction of the Wemen Solar Farm was completed in October 2018, after a very quick design and construction period of less than a year. It is now operational and can produce enough energy to power approximately 34, 000 homes in the region, whilst preventing around 117, 000 tonnes of carbon dioxide emissions.

The DC design optimisation and flexibility to provide critical deliverables in stages were key to improving development and supporting the challenging construction program.