Project Impact Assessment Method

This method calculates ‘equipment level’ energy savings where the overall reduction in electricity use is a small proportion of the total site use

About this method

The Project Impact Assessment method (PIAM) is being phased out and replaced with the Project Impact Assessment with Measurement and Verification (PIAM&V) method.  No new accreditations can be granted, and PIAM can only be used to calculate energy savings (ESCs) from implementations with an implementation date on or before 30 October 2015.

Existing accreditations

ACPs accredited to calculate energy savings using ‘annual creation’ may continue to calculate energy savings from projects implemented prior to 15 April 2016 for a maximum of 10 years from the implementation date of the project.

ACPs accredited to ‘forward create’ and ‘top up’ ESCs may continue to calculate energy savings in the following circumstances:

  • The implementation date of the project was on or before 30 October 2015
  • The end date of the total period of energy savings (ie, the sum of all periods of ‘forward creation’ and ‘top up’ for which ESCs are created) is not later than 10 years after the implementation date.

Calculating Energy Savings

Please refer to clause 7 and the associated tables of the ESS Rule for further information about calculating energy savings using PIAM.

Relevant documentation

Notice 05/2019 - Guidance on top up ESC creation under PIAM