Energy flexibility for water corporations

Chief Investigators

A/Prof Rebecca Yang  (RMIT)

Purpose of project

Water corporations in both New South Wales and Victoria have committed to a net-zero carbon emissions goal by 2050. This is largely due to the significant electricity consumption, which reaches an average of 1 MW (8,760 MWh pa) per corporation – resulting in costly energy bills and significant CO2-e emissions each year (more than 7,000 kt CO2-e). To meet this challenge head on, Sydney Water has been investing heavily in renewable energy systems that now cover 20% of its annual energy use while Coliban Water has committed to a a 13% reduction in their carbon emission rates by 2025 with 4,300 tonnes of CO2-e saved annually. 

This project will explore the potential of load management and energy trading (energy flexibility) to help them achieve their targets. It will also explore how water corporations can optimise energy efficiency and cost savings through the implementation of fixed-time load shifting and adaptive load shifting.

Additionally, it will assess the opportunities for integrating onsite renewable generation, such as biogas, hydropower, and photovoltaics electricity generation, with energy storage options. It will also look into the community solutions on renewable energy adoption by integrating surrounding DERs, such as residential rooftop PV, as a Virtual Power Plant (VPP), with community battery systems.  The load management analysis will assess Coliban Water’s own loads, loads from nearby residential/commercial customers, local distributed energy resources (DERs) and battery storage systems. A comprehensive techno-economic evaluation will be designed to adhere to network operational constraints while improving DER hosting capacity. The research will assist water corporations to better understand load management strategies so they can transition to a renewable-powered business.  

Impact of project

This research project is designed to assist water corporations and high-demand users in decision making, helping them identify practical load management approaches – like fixed time or adaptive load shifting – that reduce electricity costs and improve energy efficiency. Additionally, it can provide strategies for using renewable energy sources, such as energy trading through the National Electricity Market or peer-to-peer trading in VPPs, to provide support for a smoother energy transition with synergy between water industries and energy communities. The project should assist in creating a strategic roadmap for steadily transitioning towards renewable-powered operations, while effectively managing energy loads. Budgetary planning will be optimised based on feasibility studies provided by this initiative, so that sustainability targets are met within required timelines.  

This study will assess short-term impacts on distributed electricity network service providers, such as improving the understanding of opportunities and challenges posed by the adoption energy flexibility strategies, while long term effects can be seen through informed decision making leading to the implementation of revised flexibility strategies. Governments,  other water authorities and industrial energy users will benefit from refined research models which will be developed as part of this project. 

Progress updates

Update – September 2023

There are nine wastewater treatment plants from Coliban Water and Sydney Water selected as case studies for this project. Specifically, Coliban Water (Fig 1) has prioritised Bendigo (Epsom), Rochester, Kyneton water reclamation plants, and Echuca wastewater treatment plant. Sydney Water (Fig 2) has selected North Head, Malabar, Cronulla wastewater treatment plants, and Liverpool water recycling plants. The insights and data input from selected sites will be integrated using advanced modelling techniques to assist water utilities in leveraging their load flexibility and onsite and distributed renewable energy generations. The findings, while focused on the water utilities, could also be applied to other high-demand users with similar infrastructure set-ups. A combination of onsite renewables generation (solar PV, biogas), battery storage (EV), and load flexing, is helping them identify practical load management approaches – like fixed time or adaptive load shifting – that reduce electricity costs and improve energy efficiency.

Fig 1 Coliban Water Site Selection

Fig 2 Sydney Water Site Selection

Update – December 2023

To date, the interim progress in the project includes:

• Integration of a load management model with P2P energy trading simulation for the Epsom WWTP and a nearby VPP of 500 households with DERs, complemented by a community-based battery system for renewable energy storage, sharing, and trading.
• Implementation of a game theory-based auction platform for renewable energy trading between adjacent energy communities, aimed at increasing incentives for DERs and water utilities to enhance community welfare.
• Development of a reinforcement learning-based optimisation system to train agents for making efficient and optimal decisions in renewable energy trading and load management within the modelling framework.
• Simulation of the connected loads of the distribution network in the energy community, incorporating the information of local HV&LV lines, pole distribution, transformer capacity, and cable materials.

Knowledge sharing

• Disseminated key project insights at APSRC 2023 in the special workshop session of Solar Energy in the Water Industry.

Project partners – industry and research

RMIT (Lead), C4Net, Coliban Water, Monash University, Sydney Water 

Industry Reference Group members

Ausgrid, DEECA (VIC), NSW DCCEEW, Origin Energy, South East Water, United Energy/Powercor