Geothermal hot spots  

The Climate Spectator has an update on events in the geothermal energy industry in Australia - Geothermal hot spots.

Geodynamics has completed the first stage of its crucial fracture stimulation at the Jolokia well in the Cooper Basin, but it hasn’t been able to decide yet whether the results are good news or bad. The Jolokia wells are important to ascertain the extent of the hot dry rock resource in the Cooper Basin – a successful result would indicate that up to 6500MW of emissions-free, baseload energy capacity could be brought to the grid over the next 10 to 15 years.

However, the two fracture tests conducted at 4400m and 4700m – the deepest ever in Australia – indicated different geological behaviour to its Habanero well, with the fractures in the super-heated granite at a steeper angle and needing higher pressure to create a flow. On the plus side, the flow rate increased three-fold during the testing.

“Nature is what nature is,” said Geodynamics CEO Jack Hamilton. “Now we’ve got to take the results away and analyse what that actually means.” The most likely conclusion is that further stimulations will be required before the company can conclude that it can stick a commercial heat exchanger at the location and generate energy. “We are not there yet,” Hamilton admitted.

Meanwhile, the company’s giant rig is moving to the so-called Innamincka “shallows”, where its partner in the “deeps”, Origin Energy, will conduct drilling in the hope of identifying a commercial resource in the nearby hot sedimentary aquifers, which are only 2000-3000m deep and less hot, but also less technically challenging. The partners believe that, if drilling is successful, this resource is likely to be brought to commercial operation sooner than the deeps. Geodynamics will resume drilling at the Habanero 4 well next year, with the hope of installing a 1MW pilot plant to power the village of Innamincka installed in early 2012.

Greener pastures

Greenearth Energy has struck an agreement with aluminium giant Alcoa that could be pivotal for the development of its Geelong geothermal project. The memorandum of intent announced on Monday, and negotiated over several years, will allow Greenearth to site its production wells and generating plant on or near Alcoa’s coal mining leases, plug into Alcoa infrastructure to gain connection to the grid, and secure an off-take agreement.

Greenearth managing director Mark Miller described the MOI as a “tremendous outcome” for the company and could help it overcome significant hurdles, not least of these being financing for the proof of concept, and demonstration phases, when it will build a 12MW energy plant. “This is not a financial deal but it should make financing easier down the track,” Miller said.

Miller said he viewed the MOI with Alcoa as a further endorsement of the potential of Greenearth’s project to deliver zero emissions, base load renewable energy to the state. It hopes drilling can go ahead in the second half of 2011, with production possible in late 2012. Alcoa says it has cut emissions from its Victoria operations by 60 per cent over the last two decades and its agreement with Greenearth is part of its “big picture” response to climate change.