The system – which has yet to be proven – would work by injecting water into a borehole and circulating it through a “heat exchanger” of hot cracked rock several kilometres below the surface.

The water would be heated through contact with the rock and is then returned to the surface through another borehole where it would be used to generate electricity.

Growing concern over climate change and Flannery’s recent recognition as Australian of the Year mean a lot of people are paying attention to what he has to say about energy and the environment.

Speaking at an Australian Workers Union national conference in Queensland last month, he said planning should be underway now for the full introduction of a geothermal resource by the year 2030.

Such plans, he said, should include a huge energy infrastructure scheme that could employ many people.

Flannery said Australia’s 30,000 coal miners, whose jobs might be under threat because of moves to combat climate change, could eventually switch to working in what could soon be a booming geothermal energy industry.

In some cases, potential geothermal resources are even available in parts of the country where coal is mined, including parts of Victoria and Queensland and the Hunter Valley region in New South Wales.

But not everyone agrees that this job switch makes sense.

Petratherm managing director Terry Kallis said the skills required for the hot rock industry would be far more attuned with the oil and gas sector than with coal mining.

“I think coal mining would be a great deal more labour-intensive than geothermal,” Kallis said.

“It would be fair to say that oil and gas skills are more in line with the types of skills you would need for geothermal, primarily because anywhere between some 40-50% of capital costs with geothermal are associated with drilling.”

This potential crossover between the two industries is reflected in Petratherm’s recently announced joint venture with Beach Petroleum to develop its Paralana hot rock energy project in South Australia.

“That joint venture is not just financial,” Kallis said.

“A large part of it is the technical side where Beach brings a lot of skills to the table to help us with the drilling and the fracturing of the rock.

“In that sense, oil and gas skills are far more applicable to geothermal than other industries.”

Kallis said partnering with Beach would also help Petratherm in the wake of a growing rig shortage.

“Beach are knowledgeable in the oil and gas game and acquire drill rigs for their particular purposes regularly, so they are well experienced in terms of acquiring the services of drilling companies, which will help us immensely,” he said.

Kallis said the fact that Petratherm is looking to drill shallower than other players would also help it secure rigs.

“We’re looking to fracture the rock within the insulating rock above the granite, so we’re not looking at going as deep [as competing hot rocks players],” he said.

“That gives us a greater choice of drill rig and hopefully, though it’s not guaranteed, it also gives us greater availability.”

Hot rocks pioneer Geodynamics, in which Flannery is a shareholder, is currently experiencing rig issues of its own.

The company plans to buy its own high-tech rig from the US, so it can begin drilling Habanero-3 in South Australia’s Cooper Basin by mid-year.

The company, which believes the nation’s main geothermal resources are in the Cooper Basin, said the purchase would provide it with the most efficient rig in Australia and allow it to meet its current and longer-term drilling program.

If successful, Habanero-3 will become Geodynamics’ first commercial-scale well, leading to a 40MW power station by 2010.

But in its attempts to get it off the ground, the company hasn’t been without problems.

Its Habanero-1 well, spudded in February 2003, took a great deal longer than planned to drill, while the second, Habanero-2, didn’t spud until July 2004, almost a year later than expected.

Four months later, the company said 245m of drill stem had broken off at 4343m near the bottom of the well. The company kept trying to free the pipe until the end of June last year when it decided to halt drilling.

A technical review has now found operational techniques used in Habanero-2 were unsuitable for drilling the large sections of granite above the target fracture zone.

Despite eventually deciding to scrap the well, the company is not deterred and is now pinning its hopes on Habanero-3.

Earlier this year, Geodynamics chief executive Adrian Larking said the company was now considering buying its own high-tech drilling rig in a bid to keep its 2007 drilling program on schedule.

“There is not a rig currently in Australia that is capable of drilling commercial scale geothermal wells such as Habanero-3,” he said at the time.

On February 21, the company announced it had bought the Lightning Rig, a “state-of-the-art” drilling rig from Texas, “ideally suited” to drilling deep geothermal wells.

“The rig’s first well will be Habanero-3, planned for mid-2007, opening the way for Geodynamics to establish Australia’s first proven hot fractured rock geothermal reserves by the end of this year,” Williams said.

First published in the March issue of Petroleum magazine