Live Supply & Demand Widget, sponsored by RenewEconomy

Thanks for your interest in what has been called the “NEMwatch Widget”, or the “RenewEconomy Widget” or the “Fuel Mix Widget” (and we’re now calling the “Supply-and-Demand Widget”).  Whatever you want to call it, we hope you find it useful in understanding, at summary level, what’s currently happening in terms of electricity supply (and now demand) across much of Australia.

We appreciate the opportunity to provide this widget, with the support (via sponsorship) of RenewEconomy.
1)  This arrangement started back in 2015 and the widget has been enhanced a number of times since that time.
2)  In November 2017 we are releasing a major upgrade to enable visibility of both sides of the operation of the Hornsdale Battery Project (i.e. the Tesla and Neoen one).  This embed below is newly created, with a few kinks still being ironed out – so if you see something awry below, please let us know.

Here’s that widget again, for your convenience:


We are pleased to be able to work with the RenewEconomy team to assist RenewEconomy readers to understand how much renewable generation is currently contributing to electricity supplies in the main electricity grids across Australia.



This widget was first developed in 2015, and has been through several upgrades since that time (with some of the history described here).  In late 2017 we released an upgrade to the software to provide visibility of the Hornsdale Power Reserve project (also known as the “largest battery in the world”), which began operations on Saturday 25th November 2017 (as documented here on WattClarity).

We would like to continue developing this widget over time – and we would be grateful for whatever feedback you can provide us to guide its ongoing development.



This NEMwatch widget shows the supply and demand balance across Australia’s two main electricity grids:
1)   In the east, Australia’s National Electricity Market (NEM) covers only ½ of the Australian land-mass but accounts for roughly 90% of electricity consumed across the country.
2)   The second major grid is the South-West Interconnected System (SWIS) that supports Wholessale Electricity Market (WEM) which supplies the cities of Perth and Freemantle, and surrounding areas of south-western WA.

In the upgraded widget (from November 2017) both Generation (i.e. “supply”) and Consumption (i.e. “demand”) are shown – with a rate of generation and a rate of consumption being shown (both measured in MW or “megawatts”):

Remember that a rate of energy generation/transfer/consumption is measured in MW whereas a volume of energy generation/transfer/consumption is measured in MWh (i.e. a rate over a period of time).

The widget shows data aggregated together from several different providers – so the data has slightly different cadence and timestamps.  We have designed the widget to show the most current data available you can mouse-over a particular data point to understand more.

The following table provides a few pointers about different data sets – with more detail provided here on this page:

In Western Australia
(The WEM operates in local Perth time, which is UTC + 8 hours)
Supply Data for most of the fuel types is supplied by the AEMO West (formerly the IMO) and is of a 30-minute cadence.

This widget was updated (March 2015) to include “APVI Small Solar”, which is the estimated production from small-scale (i.e. predominantly rooftop) solar PV – described here .  This estimate is actually supplied for the whole of Western Australia, but we have made the assumption (because of population density) that this is almost equivalent to production in the SWIS.

Demand Data Being an isolated grid, supply always equals demand in the SWIS.
Across Queensland, NSW, Victoria, South Australia and Tasmania (the NEM).
(The NEM operates in Eastern Standard Time (UTC + 10 hours) and does not shift with daylight savings.  Hence for clarity it is known as “NEM time”)
Supply Data for most of the fuel types is supplied by the AEMO East and is of 5 minute cadence.

1)  It comes from the AEMO’s “Initial MW” SCADA readings taken from most of the larger generators that operate in the NEM and are allocated to respective Fuel Types using information in our Generator Catalog.

2)  In some cases where generation by a particular fuel type is relatively small (such as the case of the few bagasse-fired power stations in QLD that have data reported by AEMO) we have taken the step of leaving them classified as “Other” to save space in the legend.

3)  Where a new station appears with fuel type that is not yet set, it will appear as fuel type “Other” for an interim period.

This widget was updated (March 2015) to include “APVI Small Solar”, which is the estimated production from small-scale (i.e. predominantly rooftop) solar PV – described here .

Demand What is shown as “AEMO Operational Demand” is a number we calculate from unit level data in order to ensure that we can correctly provide visibility to consumption for charging of storage (either battery charging, or pumping to pumped storage hydro).  This means that the figure for AEMO Operational Demand does not match to a single raw data field published by AEMO.

Pumping to pumped storage hydro, being a scheduled load, is reported explicitly by AEMO.

Similarly, charging of large-scale batteries (starting with Hornsdale Power Reserve) is reported explicitly by AEMO.

Finally, there are a number of points of consumption that the AEMO can’t see (especially in real time) – such as where it is supplied by generators that operate “behind the meter”.  Small-scale PV is one example of this, but there are others (such as embedded generation on industrial sites).  As we are able to access (or estimate) other aspects of this, we will evolve our representation.

Inter-Regional Flows The NEM operates as 5 interconnected “regions” approximating state boundaries (with the ACT part of the NSW region).

By seeing the difference between supply and demand in a particular region, you are able to understand the extent to which the region is importing (or exporting) at that time.

All data is shown as close to your current viewing time as possible.



Given that the widget has been operating since 2015, we’ve fielded a number of questions about it since that time.  We’ve tried to clearly answer the most common questions here on a Frequently Asked Questions page.



This widget is one of many charts provided within our NEM-Watch™ software application.

NEM-Watch™ is a dashboard application that most of a diverse range of clients run 24×7 to enable them to keep an eye on how the NEM is operating.

In this portal here, we explain how clients use NEM-Watch to assist with:
(a) Situational Awareness
(b) Active Analysis
(c) Education and training; and
(d) More effective communication

NEM-Watch™ is just one of the software products developed by us at GLOBAL-ROAM Pty Ltd (a company focused on making the complexity in energy markets understandable to a broad range of people since 2000).



We’ve built a number of different widgets for different sponsors – each zeroed in on providing visibility of some key aspects of the energy sector, to help enhance understanding.

If you like the “RenewEconomy Widget” above, you might also like the “ECA Widget”, which has been developed to help people understand how seasonal weather drives electricity demand. You can access this:
1) Here on the Energy Consumers Australia website; and
2) Here on this NEMwatch portal; plus
3) On a growing number of third party websites (click the “Embed” button for instructions to add it to your website).



Perhaps we can help you through the development, for you, of a widget that focuses on a particular point of interest you have in the competitive energy market?

If so, please let us know: