Mouton Citrus Optimisation

Mouton Citrus is a leading producer, packer and exporter of quality citrus and Rooibos tea in South Africa, with its principal operations located outside Citrusdal in the Western Cape.

Capacity constraints with Eskom Electricity supply in the Citrusdal area, currently limits Mouton’s ability to implement its growth plans, with Eskom being unable to provide the increased power and transformer capacity required for Mouton’s expansion. This situation has led to Mouton seeking innovative solutions to optimize the energy demands of its current irrigation operations to free up the additional capacity required for packing facility expansion.
MBB Consulting Engineers was appointed by Mouton Citrus to undertake an energy use optimization study focusing on the irrigation infrastructure and the development of an optimized bulk water supply system, for a 20-year lifecycle. The optimization study focused on two aspects, namely:

  1. Optimisation of the pumping arrangement and interlinkages between three dams, three river abstraction sites and infield pumpstations for 165 ha of existing irrigation and 118 ha of planned irrigation.

For this, MBB considered multiple factors to optimise the bulk water pumping arrangements in terms of power consumption and lifecycle cost over 20 years. This included but was not limited to, variations in the pumping, pipeline layouts, pipe diameters, water sources for the infield irrigation pumpstations and the number of infield pumpstations required. The water balance between the various water storage dams was also evaluated.

An arrangement that expands the total area under irrigation by 118 ha while optimizing power consumption, capital and operational costs was also derived. This involved the siting of a single new infield irrigation pumpstation and the installation of a new pipeline and associated pumpstation to link two storage dams.

  1. Development of a farm-wide electricity supply and usage optimization plan focusing on irrigation operations.

The farm-wide electricity supply and usage optimization plan development examined the power consumption at all points in the supply network and compared this consumption to the associated transformer capacities. In most cases, the transformers had significant extra capacity available that was not being utilized. To access this capacity, MBB recommended a farm-wide microgrid with a single central Eskom Point of Connection (capacity equal to the sum of the smaller Point of Connection capacities). In this way, the existing excess capacity at each of the demand point transformers can be utilized. Additionally, there are significant savings on Eskom administration fees.

Through optimization of the irrigation operations and electrical supply network, MBB has provided Mouton Citrus with a path to unleash savings, and more critically, allow for the continued expansion and growth of its business, despite operating in a severely power-constrained environment.