Above: Project Location Map. View enlargement

Torrens Energy understands that for an area to be prospective for ENHANCED geothermal SYSTEMS, three key factors are needed:

• an active heat source which is generally radiogenic granite;
• insulating sedimentary cover over the heat source; and
• proximity to infrastructure and market.

Torrens Energy has secured the rights to explore in areas that have confirmed high heat flow, which have sediment cover with known insulating properties, and are located on the national power grid.

Torrens has been granted 27 GELs, over five project areas encompassing 21,681km² of highly prospective ground in South Australia and Victoria.

The geological setting is the Torrens Hinge Zone which is where insulating sedimentary rocks of the Adelaide Geosyncline overlap the radiogenic basement rocks of the eastern margin of Gawler Craton.

Industry Positioning

Torrens Energy is an 'upstream' geothermal resource explorer, focused on discovery, delineating and testing the viability of geothermal resources on-grid. Downstream the Company plans to participate in the renewable energy generation supply business through development partnerships with power industry leaders such as AGL Energy Limited.

The Company aims to deliver a pipeline of geothermal prospects, by applying its unique heat-flow methodology (3D-TFM), further refined by seismic surveys and intermediary validation drilling, to bring targets to deep drill-ready status.

Technical Innovation

Torrens Energy recognised the need to develop cost effective and robust broad-scale exploration techniques, to map ‘hot spots’ over some 20,000 km² of prospective geothermal geology.

Against a backdrop of technical challenges the result has been development and deployment of the 3D-TFM methodology, transforming the Australian geothermal sector in terms of site selection for enhanced geothermal systems.  This has positioned Torrens Energy as a leader in the use of innovative geothermal exploration science.

This unique approach combines advanced temperature heat flow modelling with 3D geology to identify both favourable insulators and rocks suitable for engineering underground heat exchangers, thereby allowing for the effective targeting of quality geothermal targets.

The development of this highly effective modelling was partly funded by the Australian Government Renewable Energy Development Initiative (REDI), a clear example of where industry innovation and public resources can deliver an outcome of significant national benefit.

Temperature Modeling

Temperature prediction at depth by conductive heat flow modelling using measurements recorded in shallow boreholes is an industry-standard method. The method is based on thermodynamic principals that dictate that thermal energy, measured as conductive heat flow, remains constant at depth.

The schematic representation (below) shows heat flow-drilling at approximately 15 kilometre spacing, enabling high resolution ‘heat mapping’ over large areas and providing geological control for three-dimensional modeling of heat distribution.  In Australian examples where wells have been drilled to target depths, temperature modeling has been found to reliably predict the temperature gradient to within 5% of the actual value.

Given the fact that a major obstacle facing geothermal commercialisation in Australia is the high cost of the supporting power infrastructure, the exploration undertaken by Torrens Energy on the national power grid is one of the most important geothermal developments in Australia.
 

Project Detail:  Parachilna | Port Augusta | Other