The Australian Energy Regulator (AER) has called for pricing reforms that would see solar households charged for providing electricity to the grid. The reform was suggested in response to new challenges around reliability and security as the system continues to lag behind in the integration of distributed energy resources.
Australia’s rooftop PV rose strongly over the past decade, initially spurred by premium feed-in tariffs offered by state governments. In 2019, generation from over 2 million systems met 5.2% of the National Electricity Market’s requirements. This year, rooftop PV continues to thrive even in the face of uncertainty surrounding the Covid-19 outbreak.
Nowadays, the premium feed-in tariffs are available only to a few customers in states such as Queensland, while elsewhere, such as in Western Australia, they are being phased out. Under current rules, the distribution network operators cannot charge for the use of the grid when a household exports its excess solar power.
In its report, the AER has highlighted voltage problems that are allegedly caused by the rising share of rooftop PV. “Forward and reverse power flows through a distribution network fluctuate widely during the day,” the AER said. “This fluctuation can impact the quality and reliability of power supplies at certain times, especially during periods of very high or low demand, when voltage instability is more likely.”According to the AER, these costs affect all customers but are not charged to rooftop solar owners, so are not factored into householder investment decisions.
However, the voltage issue is rather linked to the wider transformation of a centralized energy network to a “multidirectional energy system.” As AGL’s head of orchestration, Travis Hughes, told pv magazine, high network voltage levels are often “blamed on solar systems, but … our data show are high, regardless of whether or not [solar] customers are exporting to the grid.”
While the network lobby reacted favorably, many have hit back at the AER’s suggestion that solar owners should be charged for providing power to the grid. “Rooftop solar benefits all energy consumers by providing cheap power to the grid for everyone to use,” said Solar Citizens National Director Ellen Roberts. “Australian families putting solar on their roof are doing the right thing for the environment, and for other energy consumers. We need to ensure that solar continues to grow.”
“Big coal and gas generators aren’t charged for exporting their power to the grid, so why should we be slugging Australian families with panels on their roofs? If we want to look at equity in the energy system, let’s look at the big players making big profits, not Mum and Dad’s with solar,” she added.
Making rooftop solar owners pay to send energy into the grid was suggested as one of the possible solutions. Other options canvassed in the AER’s annual State of the Energy Market report include charging solar households for the use of poles and wires to transport electricity or paying them to have their panels turned off when the network is under pressure is overloaded with too much power. Both options were previously suggested by the Australian Energy Market Commission (AEMC) as long-term solutions for DER integration.
One of the recent initiatives to contain the output of rooftop PV was revealed in South Australia’s plan to stabilize its grid as it moves towards its 100% renewables goal by 2030. To address major drops in operational demand that could compromise grid stability and cause blackouts, the state government has given the green light to the Australian Energy Market Operator to switch off its rooftop PV fleet in times of emergency.