We normally think of the Northern Territory electricity chain as being divided into three main providers. These three parts of the chain are largely provided by three government-owned corporations:
But renewable energy is transforming this system. For example, consider rooftop solar on your home. No longer are you simply an energy customer, you're also an energy generator!
There are three regulated networks in the Territory:
One of the weaknesses of the NT energy system is that because it is so small the network owner PWC often doubles as the system controller, giving it an inordinate amount of power of decisions and operations.
At the moment most of the Territory's electricity supply comes from gas-fired generation, which is a fossil fuel. The proportion of renewables in the system fluctuates, with the government putting this figure at "less than 10%". Although government sources have told us that they expect the uptake of renewables within the energy grid to reach 12% by the end of 2020.
Territory Generation owns and operates eight mainly gas and diesel-powered stations across the NT, with a combined installed capacity of 593 MW. They also contract an additional 5.1MW from independent power producers, 4.1MW of which is solar, plus 1MW gas produced from the Shoal Bay landfill site.
Territory Generation is one of the NT's key institutions that favours centralised battery storage for the Darwin-Katherine grid. It issued a tender for a battery in 2017 and remains in talks with the government over the project.
The current Territory Government has a policy of achieving 50% renewables for electricity supply by 2030, "whilst maintaining secure, reliable and least-cost electricity for consumers and taxpayers".
The NT has an abundance of solar energy resources, particularly in locations south of Darwin due to comparatively less cloud cover in the wet season. We have more limited opportunities for wind and hydro, compared to other parts of the country, due to our climate and geography. This can pose a challenge for the Territory - particularly during the times of low or intermittent solar.
According to the NT's Utilities Commission, PWC estimates that in the next 12 months over 60 MW of solar PV generation will be connected to the Darwin-Katherine grid and has received inquiries in relation to connecting more than double this amount. 55 MW of large scale solar PV generation is already licensed by the commission to operate in the Darwin-Katherine system.
In addition, behind the meter solar has exceeded most expectations with around 15 MW added in 2018-19, coming to a total of approximately 59 MW of behind the meter solar in the Darwin-Katherine system. The Utilities Commission described this as "significant changes in a system with a maximum system demand of 287 MW in 2018-19".
For the fifth year running, the NT has come up last or near the bottom in most metrics in the Climate Council's annual State of Play review, which tracks the progress of Australian states and territories across a range of renewable energy targets and criteria.
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