Security of supply

In our system operator role, we work closely with industry and government to understand whether there is enough electricity to power New Zealand now and into the future. 

Our security of supply work includes looking at:

  • how much energy (or fuel) we have in the power system to meet New Zealand’s needs across a period of time
  • whether there is enough generation and transmission capacity to meet New Zealand’s electricity needs at any one point in time, such as on the coldest mornings and evenings.

Our latest Security of Supply Outlook was published on 30 September 2024. You can find it here.

We do a range of security of supply reporting, which can be accessed via the links below.

For further information, get in touch at [email protected]

Security of supply reporting

Market Operations Weekly Report The Weekly Report is usually published on a Tuesday and provides key information about the electricity market and power system, generation mix and security of supply status. It is also used for system operator announcements and a market insight is included each week that drills into key industry topics.
Electricity Risk Curves (ERCs)The ERCs, updated monthly, reflect the risk of running out of hydro storage using a standardised set of assumptions. They take account of assumed availability of generation, fuels like coal and gas, as well as the impact of hydro inflow variation on hydro storage levels over time. Simulated storage trajectories (SSTs) are included to provide an indication to the market of the risks in crossing successive risk curves. 
Annual Security of Supply Assessment (SOSA) An assessment of balance between supply and demand in the electricity system over the coming decade. This helps generators, other market participants, investors and stakeholders understand security of supply risks and assists their decision making over things like building new generation. 
New Zealand Generation Balance (NZGB)This outage planning tool helps identify whether generation and transmission capacity is sufficient to meet peak demand over the coming six months throughout the country. 
Hydro storage This page is updated weekly and provides information on lake levels, inflows and contingent storage.
Market indicators This page is updated weekly with demand profiles, the generation mix, HVDC transfer and prices, which can all indicate the market response to the current security of supply situation. 

Industry engagement

System Operator Industry ForumThis is Transpower’s fortnightly discussion of current operational and market issues with industry in its system operator role. This is for market participants only. Email [email protected] if you would like to attend.
Industry  workshops / webinarLinks to other system operator workshops and webinars for industry can be found here.

Policies and plans

Rolling Outage PlanThis plan provides for the management and co-ordination of planned outages as an emergency measure during energy shortages.
Emergency Management Policy (EMP)The Emergency Management Policy (EMP), sets out the steps that we will take, as a reasonable and prudent operator, during an extended emergency. This includes the requirement for us to initiate an Official Conservation Campaign under pre-determined conditions and, if needed, manage and co-ordinate planned outages as an emergency measure in anticipation of, or during, prolonged energy shortages.

More information

System and Market InsightsReports published here cover a range of power system and wholesale electricity market topics. They are typically technical in nature and designed for market participants but may be of use to wider audiences, including media, electricity consumers and other stakeholders. 
Overview of security of supplyThis page explains in more detail our approach to managing security of supply and how all the work we do fits together.
Learning materialThis page has a range of learning resources that we have provided to help participants better understand security of supply
Managing 2024 security of supply risksWe set up a dedicated web page over winter 2024 to keep industry up-to-date with emerging security of supply risk related to hydro storage reaching historic lows. We are no longer updating this page but you can still access it here.
Media releases System operator media releases related to security of supply can be found on Transpower’s News page. You can sign up to receive media releases here.
News from TranspowerThe latest security of supply information may be included in Transpower’s monthly newsletter rounding up all the latest happening from across the business. You can subscribe to receive this here.