From time to time, the electricity market is subject to price changes. We’ll make sure we give you advanced information about the changes, why they are changing, and how they affect your business.
Capacity charge changes
To ensure there’s enough electricity to meet the highest demand periods (generally during the hottest days of the year), the Australian Energy Market Operator (AEMO) encourages investment in electricity generation through a capacity mechanism. The capacity mechanism includes setting capacity prices for generation which is factored into your capacity charge, as defined in the Capacity Charge Formula.
|Effective||1 October 2022|
|What this means for you||
If you have an Electricity Sales Agreement which can sometimes be referred to as an unbundled agreement, your capacity charges will change from 1 October 2022. Your individual capacity charge is affected by your business’s consumption during the 12 Peak SWIS Trading Intervals. For more information see our frequently asked questions below or to learn more about how capacity works, head to synergy.net.au/capacitycharges
Changes to capacity charges: Your questions answered
How and when you run your business has an impact on your electricity costs. To help you make sense of how capacity charges are calculated and charged, we’ve answered the most frequently asked questions about the capacity market in WA.
- Does everyone pay capacity?
Yes, all customers contribute to the cost of capacity. Capacity costs are calculated by AEMO and your share of capacity costs are calculated by Synergy in accordance with your terms and conditions of supply. The amount you pay depends on how your business contributes to peak system demand to allocate the cost of capacity fairly.
- How does my usage impact my capacity costs?
Capacity charges are payable for each capacity year from 1 October to 30 September. To keep things fair, your capacity charges are calculated based on your usage during the '12 Peak SWIS Trading Intervals' for the previous capacity year.
The 12 Peak SWIS Trading Intervals are determined by AEMO who identify the 12 trading intervals (half hourly periods) for the preceding capacity year based on the four days that had the highest demand for electricity in the SWIS between 1 December and 31 March. The three trading intervals (half hourly periods) in which electricity demand was at its highest on these days are the 12 Peak SWIS Trading Intervals.
The median amount of electricity your business uses in the 12 Peak SWIS Trading Intervals is known as your Median Peak Load (MPL) and used to calculate your capacity charges for the next capacity year. The higher your MPL, the higher the capacity charges will be for your business.
- How is capacity managed?
As the market operator, AEMO has responsibility for managing capacity in the SWIS and does this through the administration of the Reserve Capacity Mechanism. The Reserve Capacity Mechanism is an element of the WEM that is designed to ensure that there is enough generation capacity available each year to meet demand at any time including during peak system demand periods.
Through the Reserve Capacity Mechanism, AEMO pays generators for making their generation available to meet demand for electricity at all times including peak system demand periods. The total costs associated with obtaining this capacity are then allocated to electricity users based on their contribution to peak demand the previous capacity year.
- Is there a way to reduce my capacity charges?
To reduce your future capacity charges you can look to reduce your electricity consumption between 4pm and 8pm during the hottest days between December and March when demand is generally highest.
It’s important to note that what you use during peak periods from December to March this year won’t have an impact on your capacity charges until the following capacity year, which starts on 1 October each year.
- What impacts capacity prices?
The Reserve Capacity Price is part of the Reserve Capacity Mechanism and determined by AEMO. This price is used to calculate your capacity charges and is influenced by a number of factors including: type of generation plant in the SWIS, new generation or expansions, forecast peak demand and system security requirements.
- What is a capacity year?
This is the period from 1 October to 30 September each calendar year for which the amount of capacity required is determined and capacity charges allocated.
- What is capacity?
Capacity represents the need for adequate generation resources to ensure WA’s electricity supply is reliable and the demand for electricity can be met at all times.
To understand how the capacity market works in WA, it helps to know these key terms:
- SWIS – This is the South West Interconnected System, which is the grid (or electricity distribution network) that covers the south-west of WA.
- WEM – This stands for the Wholesale Electricity Market, which is the electricity market for the SWIS.
- AEMO – The Australian Energy Market Operator is the body which oversees the operation of the WEM which includes the electricity and capacity market.
- What were the 12 Peak SWIS Trading Intervals for this capacity year?
The 12 SWIS Peak SWIS Trading Intervals determined by AEMO which were used to calculate capacity charges for the capacity year beginning 1 October 2022 and ending on 30 September 2023 were:
Peak Trading Interval
19 January 2022
5:30pm to 6:00pm
6:00pm to 6:30pm
6:30pm to 7:00pm
21 January 2022
5:30PM to 6:00PM
6:00PM to 6:30PM
6:30PM to 7:00PM
3 February 2022
6:00PM to 6:30PM
6:30PM to 7:00PM
7:00PM to 7:30PM
16 February 2022
5:30PM to 6:00PM
6:00PM to 6:30PM
6:30PM to 7:00PM
- When does peak demand occur?
Peak demand is based on the overall electricity demand in the SWIS, which includes both business and residential energy consumption.
It is therefore impacted by weekends, public holidays and school holidays and will be highest when both businesses and residential households are using electricity at the same time. Demand for electricity also tends to rise when temperatures increase. For example, when we experience consecutive hot days, air conditioners are in constant use to combat accumulated heat in buildings and homes.
Solar PV installation helps to reduce the amount of demand on the system (or demand to be supplied from generation) during the day but later in the day it becomes less effective and can also be unpredictable.
Usually peak demand occurs on weekdays between 4pm and 8pm.
Small-scale Renewable Energy Scheme (SRES) charges
Supports the investment in smaller technologies such as rooftop solar panels and solar hot water heaters through the generation of Small-scale Technology Certificates (STCs). The number of STC’s to be purchased each year is calculated using the Small-scale Technology Percentage (STP) published by the Clean Energy Regulator.
|Effective||1 January 2023|
|2023 rate||16.29% STP|
|If you have an Electricity Sales Agreement, your SRES charges are likely to change. The STP has decreased from 27.26% in 2022. Learn more at the Clean Energy Regulator or see our frequently asked questions below.
Large-scale Renewable Energy Target (LRET) charges
Supports the development of large projects including wind farms and solar power stations by legislating demand for Large-scale Generation Certificates (LGCs). The number of LGC’s to be purchased each year is calculated using the Renewable Power Percentage (RPP). which changes annually and is published by the Clean Energy Regulator.
|Effective||1 January 2023|
|2023 rate||18.96% RPP|
|If you have an Electricity Sales Agreement, your LRET charges are likely to change. The RPP has increased from 18.64% in 2022. Learn more at the Clean Energy Regulator or see our frequently asked questions below.|
- What is the Renewable Energy Target?
The Renewable Energy Target (RET) is an Australian Government scheme designed to reduce emissions of greenhouse gases in the electricity sector and encourage the additional generation of electricity from sustainable and renewable sources.
- The Large-scale Renewable Energy Target (LRET), encourages investment in large renewable power stations like wind farms and large scale solar farms to achieve 33 000 gigawatt hours of additional renewable electricity generation by 2020. The annual target will be rising each year in order to achieve this target.
- The Small-scale Renewable Energy Scheme (SRES), supports small-scale installations like household solar panels and solar hot water systems.
- What does the Renewable Energy Target mean for my energy costs?
In order to meet the Federal Government’s Renewable Energy Target (RET) Synergy is liable to purchase a certain amount of renewable energy for you each calendar year. This is done through the purchase of renewable certificates from large renewable power stations and the owners of small-scale systems who are eligible to create certificates for every megawatt hour of power they generate.
- For the Large-scale Renewable Energy Target these certificates are known as “Large-scale Generation Certificates” (LGCs). The number of LGCs to be purchased each calendar year is calculated using the Renewable Power Percentage (RPP), set annually and published by the Clean Energy Regulator (CER) in accordance with the Renewable Energy (Electricity) Regulations 2001 (Cth). For example for 2020 the RPP is 19.31% which means Synergy must purchase LGCs for 19.31% of your energy consumption; and
- For the Small-scale Renewable Energy Scheme Synergy purchases “Small-scale Technology Certificates” (STCs). The number of STCs to be purchased is calculated using the Small-scale Technology Percentage (STP), set annually and published by the Clean Energy Regulator (CER) in accordance with the Renewable Energy (Electricity) Regulations 2001 (Cth). For example in 2020 STP is 24.40% which means Synergy must purchase STCs for 24.40% of your energy consumption
- How are Renewable Energy Target charges shown on my bill?
For customers on an Energy Sales Agreement or other Synergy contract where renewable energy charges are passed through, you can see a line item on your bill for the Small-scale Renewable Energy Scheme charge and the Large-scale Renewable Energy Target charge.
- What is happening?
The Clean Energy Regulator (CER) publishes the Small-scale Technology Percentage (STP) and Renewable Power Percentage (RPP) by 31 March each year, for the relevant calendar year. Your bill will be adjusted after the STP and RPP have been published to reflect your consumption from 1 January.
The CER has published the STP and RPP for 2022:
Scheme Rates 2020 2021 2022 2023 Small-scale Renewable Energy Scheme STP 24.40% 28.80% 27.26% 16.29% Large-scale Renewable Energy Target RPP 19.31% 18.54% 18.64% 18.96%
- How are these rates derived?
The Renewable Power Percentage (RPP) and Small-scale Technology Percentage (STP) are broadly derived by calculating the required renewable power generation (either large scale or small scale) by the amount of electricity used in Australia (not including self-consumption by customers of the electricity generated by their solar photovoltaic (PV) systems and electricity consumed by Emissions Intensive Trade Exposed activities). Note these are federal schemes and therefore include renewable power generation in all of Australia; there is no assessment of state based renewable energy policies.
- Why have they changed?
Renewable Power Percentage (RPP)
- The Large-scale Renewable Energy Target (LRET) has reached the 33,000 GWh annual target mandated by the government from 2020 to 2030.
- Over the past few years the volume of electricity consumed in Australia has been relatively static, resulting in the RPP not changing significantly from year to year.
Small-scale Technology Percentage (STP)
- The STP is determined based on the estimated number of Small-scale Technology Certificates (STCs) that will be created during the year from the installation of eligible small scale generation (such as solar photovoltaic (PV) systems, solar hot water systems, heat pumps etc.).
- It is important to note that the number of STCs created is determined from the time of installation of the small scale renewable energy generation technology until 2030. This means there is more volatility in the STP and it can increase or decrease year to year.
- The estimated number of STCs created is adjusted based on the difference between the previous year’s estimated number of STCs created and the sum of the STCs surrendered.
- Who is impacted by the change?
For customers on a Business Flexi product, your renewable energy charges are built into your existing energy rates and supply charge and there is no change to your SRES or LRET charges.
Customers on other products in which renewable energy charges are passed through will be directly affected.
- When will Synergy start charging the new rates and what does this mean for my energy charges?
If you are on an Energy Sales Agreement or product where renewable energy charges are passed through, the relevant charges for your consumption this year have been based on the 2022 percentages.
As the Clean Energy Regulator (CER) has now published the 2023 percentages, Synergy will adjust your account to backdate the commencement of the STP and RPP for 2023 to 1 January 2023. This will be reflected in your April or May bill issued after 31 March 2023.
- What is Synergy doing to inform its customers of the new percentages?
Synergy will be notifying customers of the new RPP and STP for 2023.
The RPP for 2023 has increased compared to the RPP for 2022 and consequently you can expect your Large-scale Renewable Energy Target charges will increase in 2023 based on the same total electricity consumption.
The STP for 2023 has decreased compared to the STP for 2022 and consequently you can expect your Small-scale Renewable Energy Scheme charges will decrease in 2023 based on the same total electricity consumption.
- Where do I go for more information?
The Economic Regulation Authority has approved there will be no increases to the price Western Power charges Synergy to access its electricity network.
|Effective||1 July 2023|
|2023 charge||The Economic Regulation Authority (ERA) has approved changes to Western Power's network Network Access Charges which will take effect from 1 July 2023.|
|For customers on a fixed-term Synergy business plan (Synergy Business Flexi or Synergy Business Fixed) there will be no changes to your . For customers on an Energy Sales Agreement (ESA), Network Access Charges are passed through to you in accordance with the applicable agreement terms and conditions and will appear as a separate line item on your bill.|
Electricity - Government regulated tariffs (standard contracts)
The setting of electricity retail tariffs is determined by the state government and is assessed as part of the annual state budget process every year.
Gas distribution charges
The Economic Regulation Authority has approved changes to the price ATCO Gas Australia charges to distribute gas through its network.
|Effective||1 January 2023|
|2023 rate||Please contact your account manager to confirm increase (if applicable)|
|What this means for you||For customers on a fixed-term Gas Sales Agreement - Form of Agreement these changes may be passed through to the rates your business pays.|
Explore your options
Reduce your carbon footprint
Support a growing industry and purchase some of your energy from renewable sources.
Consumption & expenditure reports
We provide customised reporting tools so you can monitor, forecast and adjust your consumption.