Renewable PPA Tool

Power Purchase Agreements (PPAs) with utility-scale renewable energy plants allow medium to large-scale electricity consumers to meet a proportion of their demand using renewable electricity. This allows them to reduce their greenhouse gas (GHG) emissions while at the same time reducing their exposure to high and volatile wholesale prices in the NEM.

Such agreements, however, must be brokered through a retailer due to the structure of the NEM. The agreements that are required involve complexity around allocation of the benefits and risk associated with the renewable energy project and the residual load that must be met via the retailer. There is therefore uncertainty around the financial case for projects, and how this compares to other options such as on-site projects. This is a significant barrier to the uptake of PPAs. Once a PPA has been entered into, there is also significant additional complexity for the energy consumer to track and report the financial and environmental outcomes of the project, including renewable energy certificates, and so ensure that the terms of the contract are being met.

We have developed tools to assist large energy users, energy consumers, buyers’ groups and local government to:

1. Contract with off-site renewables projects through a PPA and therefore meet their renewables and emissions goals  

  • Estimate the future costs of different energy and network supply contracts for large energy consumers, building on existing UNSW tariff analysis tools
  • Assess potential on-site renewable energy deployment options in terms of technical and environmental performance and financial viability
  • Explore opportunities for off-site renewables deployment through different possible PPAs, and associated retailer tariffs
  • Evaluate possible demand-side options to increase the value of both on-site and off-site renewables deployment.

2. Assist in PPA monitoring, to ensure value for energy consumers:

  • The tool can be applied during the operation of a PPA in order to ensure compliance, emissions outcomes and financial value for the energy consumer.

This project is supported by the CRC for Low Carbon Living and builds on a previous project that involved over 50 stakeholder interviews, analysis of market survey data to distil participant drivers and preferences, six project case studies, and two stakeholder engagement workshops. 


Download the PPA Tools!

There are four tools available, as below, and there is also a User Manual.

PPA modelling tools - Renewable PPA Yearly Framework and Templates

Detailed modelling tools for replicating PPA contracts using one year of data. These tools can be used for detailed forecasting and scenario modelling of future PPAs and for bill replication and monitoring of current PPA contracts to ensure compliance.

The Template Tool is available here and the Framework Tool will be available soon.

PPA risk analysis tool (available soon)

This is a simplified modelling tool that allows the estimation of costs during the whole PPA contract period. Several parameters can be changed to assess the potential risks of the project over its lifetime.

PPA NEM data tool - NEM Price Data

Access to historical NEM data in a format compatible to the PPA tools.

Available here.

PPA Solar data tool - NEM RE Generation Data

Access to historical solar farm data in a format compatible to the PPA tools. It also allows users to scale the solar data in order to model farms of different sizes.

Available here.


UNSW Research Project Team:

Jose Bilbao

Nicholas Gorman

David Richardson

Robert Passey

Anna Bruce

Iain MacGill