Renewable Energy Certificates (REC) Calculator

Recs are categorised in two types:

STC’s: Small Scale technology Certificates      


LGC’s: Large Scale Certificates.

STCs are for PV systems of less than100 kW, wind systems less than 10 kW, and all solar hot water systems. LGCs are for systems larger than 100 kW for PV and larger than 10 kW for wind systems.

Recs may also be created with other forms of renewable energy; these types can be found on the Clean Energy Regulator’s website at

RET Australia has links to two types of calculators: The Small Generation Unit Calculator and the Solar Water Heater Calculator.

The calculators are available through the following links:

Small Generation Unit STC Calculator:

Solar Water Heater STC Calculator:

These calculators allow a person to quickly and easily determine how many Renewable Energy Certificates “Recs” that a proposed system will be eligible for.

The REC Calculator is a simple and easy tool to use, but serves only as an approximate guide to the number of Recs that will be created for any given installation. To ensure an accurate assessment is provided, contact the staff at RET Australia to be sure of the calculation process.

The Small Generation Unit Calculator (for small-scale solar panel, wind and hydro systems) and the Solar Water Heater Calculator are designed to assist members of the public in determining the approximate number of Small-scale Technology Certificates (STCs) that may be created under the Small-scale Renewable Energy Scheme in relation to an installation. The Calculators are designed as an approximate guide only, and do not provide an accurate assessment of the number of STCs that can be created for an installation.

RET Australia has linked to these Calculators which are provided by the Clean Energy Regulator (CER). Information is provided as a guide only and to the maximum extent permitted by law, and without limiting any other disclaimer made by the CER and gives no warranty and makes no representation as to the availability, accuracy, completeness, currency, quality, reliability or fitness for purpose of any data obtained from using the Calculator.

In particular you should be aware that:

The REC Calculator does not take into account all of the variables which may affect the calculation of the STCs for an installation; and

the REC Calculator is based on data which may be updated from time to time and therefore results using the Calculator may vary over time.

RET Australia recommends that you should not use the Calculator as the basis for making any decision or embarking on any course of action. In order to accurately calculate the number of STCs that can be created for an installation, you will need to consult the Renewable Energy (Electricity) Act 2000 and the Renewable Energy (Electricity) Regulations.

CER means the Commonwealth of Australia as represented by the Clean Energy Regulator and any reference to the CER includes a reference to the Regulator.

Every time a renewable power system is installed, a number of Renewable Energy Certificates or “Recs” are also created. The property owner can claim these Recs themselves or receive a financial benefit from an installer off the fully installed system price.

One Rec is the equivalent of 1 megawatt hour of renewable energy production, and renewable energy systems have varying “Deeming” periods that allow a system owner to forward claim their Recs within one year of the installation date.

Once Recs are processed (either by an registered individual or registered agent), these certificates are purchased by liable parties (traditionally power companies) who need to offset their non-renewable energy production based on set parameters provided by the federal government. These Recs are similar to stocks or bonds and are tradable commodities and have their own trading markets. They also have their own unique accreditation or serial number which allows each system to track just how many Recs have been generated for a single installation and who has purchased the recs throughout time.

The large liable entities that eventually purchase these Recs are required to surrender Recs on a quarterly basis to meet their surrender targets.