WA may not have to meet Opposition Leader Bill Shorten’s 50 per cent green energy target after Federal Labor said it would not be applied uniformly across the country.

Responding to claims local energy consumers were facing almost $1 billion a year in extra costs by 2030 under Labor, shadow energy minister Mark Butler condemned what he said was a scare campaign.

The Public Utilities Office has said supplying 50 per cent of WA’s power from renewable sources by 2030 would add $7.3 billion in costs over a baseline scenario.

But Mr Butler said the modelling was flawed because it presumed WA would need the same benchmark as other States when this was not necessarily the case.

Some States such as South Australia and Tasmania, he said, would do much more of the heavy lifting.

He said the PUO’s analysis, and criticism of Labor’s policy was “just another anti- renewables scare campaign — same as we’ve seen for the last 10 years of Abbott-dominated climate wars”.

“Labor’s renewable energy target isn’t State-based,” Mr Butler said. “This isn’t an analysis of Labor policy. Given the differences between States, it’s very unlikely all States will need to reach 50 per cent renewables by 2030 in order to meet our commitment.

“For example, South Australia is projected to reach around 75 per cent by 2025, Tasmania is already almost 100 per cent renewable, and some States will do less. This isn’t modelling of Labor policies and it’s not modelling of electricity prices — it’s the renewable investment needed to reach 50 per cent in WA. Renewable energy is the best plan to lower the energy bills of WA households and small businesses.”

The PUO found that under a baseline scenario, the share of WA’s power coming from renewable sources was likely to be 33 per cent — 3124MW — by 2030.

Most of the investment in new capacity, however, would happen before the 2020 deadline for the current green energy target.

The PUO said a 50 per cent green energy share by 2030 would amount to more than 4600MW, an additional 1500MW over and above the baseline.

According to the PUO, about $560 million of the extra annual cost to WA would come from wind farms and solar projects that would need to be built to ensure the State met its share.

It also estimated an extra $116 million a year would needed for “flexible ramping services” such as fast-response gas-turbines that could be used when the sun was not shining or the wind was not blowing. More than $200 million a year would be needed for upgrades to accommodate the new green power projects on the networks of poles and wires run by companies such as Western Power.

Despite the capital costs needed for the new plants and upgrades, the PUO noted the operating costs of renewable projects were “negligible”.

The report also failed to consider the effects of batteries on the grid, even though the PUO concluded “it is reasonable to assume that batteries would only reduce the cost of meeting the target”.