WEMDE

The previous WEM Balancing Market and Load Following Ancillary Service (LFAS) markets were replaced by the new Real-Time Market (RTM) which co-optimises Energy and Essential System Services (ESS). AEMO’s previous Real-Time Dispatch Engine (RTDE) was not capable of co-optimisation and was replaced to enable AEMO to operate the new RTM. The WEMDE project replaced the RTDE with a modified version of the  dispatch engine used in the National Energy Market, which is also operated by AEMO. This system is called the WEM Dispatch Engine (WEMDE) and co-optimises Energy with the ESS services in accordance with the RTM design.  

In addition to providing real-time dispatch capability, the WEM Dispatch Engine was critical in the implementation of the new ESS framework including:

• Allocation and dispatch of Regulation, Contingency and Rate of Change of Frequency (RoCoF) services,
• Determining pricing outcomes,  
• Producing forward-looking dispatch schedules up to one week ahead, and
• Providing data for several downstream publication requirements (binding and near-binding constraints) and settlement outcomes (ESS activation, dispatch compliance, net offer shortfall).

Determination of the Dispatch Algorithm, the various constraints that it needs to cater for and the associated violation penalties, was a key part of developing the WEMDE solution. 

WEMDE’s partner project, WEMDE User Interface (UI), also delivered a new UI to allow AEMO’s Power System Operation (PSO) Controllers to manage dispatch in the Control Room. The WEMDE UI replaced the Controllers’ previous UI and connects to the new WEM Dispatch Engine.