The ACT’s ambitious push for 90 per cent renewable energy by 2020 could be at risk, with a local energy and climate economist saying it could become too difficult in coming years.

Director, of ANU’s Centre for Climate Economics and Policy, Dr Frank Jotzo, says that the repeal of the carbon tax and likely watering down of the national RET could push the ACT’s goal out of reach.

With the offers by renewable energy developers dependent on the complex layers of state and federal policy, Dr Jotzo says the ACT will need to form policy and spend its funds very carefully to hit the target.

Speaking to The Canberra Times, Dr Jotzo says it would be worth it if the ACT can reach its goal of each household's additional energy cost peaking at $250 a year in 2020.

“The ACT, by continuing with their renewables policy, will stand out more in the national context [and] it will be for the time being, the only remaining beacon of an ambitious renewable energy policy,” he said.

He says the Renewable Energy Target will almost certainly watered-down if the LNP is re-elected at the 2016 federal election, and that wholesale prices will fall due to the carbon tax repeal.

He also believes that wind power will grow to play a greater role in ACT energy generation, despite Federal Treasurer Joe Hockey considering wind farms “a blight on the landscape”

“You may even expect that the prices demanded by wind power developers, and solar developers in the second solar auction, may well be lower as a result of winding back of federal climate change policies, simply because there is less demand for renewable energy development across Australia,” Dr Jotzo said.

“At the same time, the way contracts are structured for solar and wind power producers under the ACT auction system, they will need to be paid a bigger gap payment, if the wholesale price is lower.

“For the amount of electricity produced by the renewable generators under an ACT contract, that wholesale price reduction will be a net zero, because whatever we save on wholesale price, will have to be added in paying the larger gap payment.

“There will be other changes as well... if the RET is watered down, that will have an upward effect on wholesale prices in the national electricity market, because you will get less renewable energy into the grid than you otherwise would."

Dr Jotzo is speaking at a clean energy seminar at the University of Canberra tonight.