After 40 years as an engineer in oil and gas - most recently a senior executive at Woodside Petroleum - it gradually struck Stephen Rogers that something was wrong.

So he made a break for the sunny uplands of renewable energy, and became chief executive of Protean Energy, a former miner trying to commercialise proprietary wave energy technology.

"I developed an interest in renewable energy technology over a period of time as I started to realise how many tonnes of carbon dioxide and noxious gases are produced in industry around the world," Rogers, 61, tells The Australian Financial Review.

"I am not someone who enters into long debates about climate science but I do recognise that we are polluting the earth and that the level of respiratory diseases and related diseases is increasing and we have got to do something about it."

Rogers' conversion came a decade after former BP Australia chief Greg Bourne made his startling leap from the oil patch to running the WorldWide Fund for Nature, and after a year of milestones for clean energy.

In August the International Energy Agency reported that the installed capacity of renewable energy - wind solar and hydro - had passed that of coal by the end of 2015, although coal still generated more power. Solar costs continued to fall, and batteries got a big boost from the Tesla Powerwall 2 and South Australia's epic statewide blackout in September.

Bourne also spent time on the board of Carnegie Clean Energy - a rival wave power developer to Protean that is embarking on its first commercial trial in Cornwall, England.

"I decided after serving the oil and gas industry for 40 years that I could make a contribution to the whole effort to move to a lower carbon future," Rogers says from his Cottlesloe, Perth home where he has 5 kilowatts of solar panels on the roof.

He became Protean's chief executive in August. The shares were around 1¢ - down from 5.8¢ in May 2015 - the register was institution-free and the company had all its eggs in wave energy.

Rogers has broadened its horizons to embrace commercialising vanadium redox flow battery technology - in which it has a half share with a Korean partner - and building a solar contracting and operating business aimed at small and medium enterprises.

He brought in offshore engineers to redesign Protean's Wave Energy Converter - which harnesses all six actions of waves to generate electricity - for concept trials.

Next is a commercial trial which the company hopes will take place in the second half of next year and cost between $2 million and $3 million. That will require a capital raising. Rogers hopes to get some institutions on board and complete the issue by the end of March.

Protean aims to produce wave energy for less than the 50¢-$1 a kilowatt hour it can cost remote communities and islands to generate power from diesel and solar, and target ecotourism and agriculture.

"We are not targeting grid power. We are targeting niche markets and keeping the technology simple," he says.

VRF batteries generate electricity by passing vanadium solutions with different numbers of ions over a graphite electrode. Rogers says they have twice the life of established lithium ion batteries - 15-20 years - and won't leave toxic waste. The next step is to prove it can make them.

He says small and medium firms - warehouses, workshops and buildings - are a big untapped market for solar battery systems. He is looking for revenue from this in the March quarter.

There's a way to go but Rogers says Protean now has a strong team of engineers, a growth plan and some runs on the board. "It's really about shaping the business to match the emerging renewable energy industry."