AEMO assessments questioned
Experts say WA will see power price hikes unless it realises how popular rooftop solar is.
Rooftop solar in WA has grown by almost 20 per cent in recent years, upsetting the fossil-fuel-heavy electricity market.
Researcher Bill Grace from the University of Western Australia says the energy regulator — the Australian Energy Market Operator (AEMO) — greatly underestimates the future uptake of renewable energy in Western Australia.
He said the excitement around solar could result in higher power prices.
“With the current scenario, over the next 20 years we're talking about significant increases in tariffs — 50 per cent perhaps,” Professor Grace told the ABC.
“To try and protect this legacy, coal-fired generation units will just keep prices high, and will also waste power people have purchased solar panels to produce.
“As there is more private solar produced, the network has to generate less electricity, but because a lot of the costs in the system are fixed, the unit cost — that is the cost per unit of energy — can only rise.
“The impact will be felt by about 2025, when there will be so much solar energy being exported from private houses that it will start to impact on the generation on the network, particularly coal-fired generation or baseload power.
“The private solar from houses and businesses exported onto that network effectively reduces the demand below the level that baseload coal can operate.”
AEMO modelling is based on the idea that rooftop solar energy will grow at a linear rate, but Professor Grace says that modelling is flawed, as the market is growing at an exponential rate.
He said AEMO’s linear modelling underestimates the amount of solar and storage on the grid, and its subsequent impact on the conventional generation network.
“So one of two things can happen. Either the coal-fired power generation is switched off or alternatively, the private solar will have to be switched off,” he said.
The WA Government is sticking with AEMO’s projections and advice.
“AEMO is the trusted authority on providing forecasting and security advice as it draws information from a range of experts, including industry and governments, and I have total confidence in its advice,” Energy Minister Mike Nahan said.
“The latest Australian Energy Market Commission report confirms West Australians continue to pay among the lowest in Australia for electricity.”