It will be about a decade before it is clear whether small nuclear reactors are suitable for Australia and would take about 15 years to bring a plant online if a decision was made to build one, one of the country’s leading experts has said.

But Ziggy Switkowski, who headed a 2006 review of nuclear power for the Howard government, said the technology had no chance of being introduced unless Australia had a coherent energy policy.

“Can you graft a long-term commitment to nuclear energy on to a currently unconfirmed national energy policy? The answer to this is no, in my opinion,” he told the first hearing of a parliamentary inquiry into what would be necessary to develop a nuclear power industry.

The inquiry was called by the energy minister, Angus Taylor, following calls from backbench MPs for nuclear to be reconsidered. Taylor said there were no plans to drop the existing moratorium on nuclear energy but it was government’s role to plan for the decades ahead.

Switkowski said though nuclear power had “no social licence at this time” the legislative ban against it should “absolutely” be abolished. “We really should not be making decisions in 2019 based on legislation passed in 1999 reflecting the views of 1979,” he said.

He reiterated his belief that the window for large-scale nuclear plants had closed, a view shared by Taylor, but said he believed there would be an opportunity for small modular reactors, known as SMRs, of between 60 and about 200 megawatts.

He said they were most likely to be successful in regional communities with about 100,000 people or in powering mining or desalination sites. “But we won’t know until the SMRS are deployed in quantity [overseas],” Switkowski said. “That’s unlikely to happen for another 10 or so years.”

He listed the positives and concerns associated with developing a nuclear industry. The disadvantages included that, given historic disasters at Three Mile Island, Chernobyl and Fukushima, “the possibility of catastrophic failure in a nuclear system is non-negligible”.

He said conventional nuclear reactors were “now very expensive”, partly due to safety requirements in the wake of the Fukushima disaster. Nuclear power was the most capital-intensive energy technology and took the longest to recoup investment. Unlike with solar and wind energy, there did not appear to be economies of scale – the cost of nuclear electricity grew as technology advanced. Switkowski said as far he was aware, no coherent business case to finance an Australian industry had been presented. Any business case would require significant government support.

“Given that Australia would begin from a standing start, the first reactor of any commercial scale would take about 15 years to reach normal operation and generate revenues,” Switkowski said.

Based on experience overseas, he said it was more likely that 15 years would be an underestimate than an overestimate of how long it would take. He said the commercial and political risks of developing an industry over what could be more than five political cycles were substantial.

Positives included that nuclear reactors were comparable to renewable energy in terms of emissions and would help meet national greenhouse targets.

“In theory, the phasing out of coal-fired power stations and the phasing in of nuclear reactors could make a lot of sense,” he said.

Switkowski said nuclear was highly efficient, did not depend on the weather and could operate around the clock. Australia was well suited to support a nuclear fleet as it had strong environmental standards, capable regulators familiar with radiation safety, was geologically stable, had a technologically capable workforce and was home to a third of the world’s economically recoverable uranium.

He said the role of government should be to produce a coherent national energy strategy with bipartisan support that was technologically agnostic, balanced cost with resilience and risk, met emissions targets and restored energy as a source of national competitive advantage.

Nuclear should be considered alongside all other technologies, including solar and wind backed by batteries and pumped hydro storage, he said. “It may mean nuclear is not to be the preferred baseload generator, but we don’t know.”

The inquiry by the standing committee on the environment and energy is due to report back later this year.