Standards Development

Scope

This technical specification is to provide the guideline and technical requirements for the evaluation of virtual power plant output, including the relevant terms, general requirements, evaluation data, evaluation indicators, evaluation process, evaluation results, and applications. 

This document applies to virtual power plant as defined in IEC TS 63189 -1, which is a party or system that realizes aggregation, optimization and control of distributed generation, energy storage devices and controllable loads.

Note 1: The aggregated distributed generation, energy storage devices and controllable loads are not necessarily within the same geographical area.

Note 2: The party or system is to facilitate the activities in power system operations and the electricity market

Purpose

Virtual power plant (VPP) provides an efficient way to utilize distributed energy resources (DER) and other flexible resources on the demand side. With VPP, these resources can participate in electricity market transactions in an aggregated way, where the resource owners can acquire economic interests; the grid operator can benefit from using these dispatchable resources to support grid operation; the community can benefit from deferring investments in constructing new power plants and grid renovation. By facilitating the use of DER, VPP also serves the climate action of SDGs.

With the rapid growth of DER, VPP are more accepted and developed around the world. For the operation of VPP, the output evaluation is a crucial step. It provides important information such as generation capacity, response time, generation duration, ramp r ate and generation accuracy. These are of great importance to the market access assessment, transaction settlements, and VPP optimization.

The VPP output evaluation is significantly different from the electric quantity measurement in conventional billing. Firstly, a conventional power plant has a clear physical access point to the system, and the needed operation parameters can be directly me asured by energy meters without considering power losses. While, a VPP is a dynamic aggregation of widely distributed resources and does not have a unified physical access point. So, the operation parameters and indexes cannot be directly measured, but need to be calculated from the operating data of the participating resources. Secondly, although the resources could have been already metered, the data needed for VPP operation and settlement includes many indexes that are not used or necessary for the resou rces, such as high precision power or energy metering and ramp rate. Compared with conventional resource communication, the VPP output evaluation has much higher requirements for resource communication, such as bidirectional communication, low latency.

So far, the indexes and methods for VPP output evaluation have no specific international standard to use. This is a prominent issue considering the resources aggregated in a VPP can be geographically dispersed and a VPP may participate in multiple electric ity markets. IEC TS 63189-1 standardized the concept, framework and general functional requirements of VPP. But there are standard gaps for specific indexes and evaluation methods.

This proposal intends to fill this gap with specifications for the types of indexes, data and measurement requirements, and calculation methods, as well as process for evaluation, including the data objects, requirement and calculation preparation. It will benefit various stakeholders such as VPP operators, utilities, operators and organizations for electricity markets by providing a transparent and standardized approach to facilitate the implementation of VPP.