Tidal Energy in Australia Assessing Resource and Feasibility in Australia’s Future Energy Mix November 2020 Final report of the Australian Tidal Energy (AUSTEn) three-year project to map Australia’s tidal energy resource in detail and assess its economic feasibility and ability to contribute to the country's renewable energy needs Citation Enquiries The suggested citation for this report is: Professor Irene Penesis Penesis, I., Hemer, M., Cossu, R., Nader, J.R., Australian Maritime College Marsh, P., Couzi, C., Hayward, J., Sayeef, S., University of Tasmania Osman, P., Rosebrock, U., Grinham. A., E: [email protected] Herzfeld, M. and Griffin, D. (2020). Tidal Energy T: +61 3 6324 9770 in Australia: Assessing Resource and Feasibility in Australia’s Future Energy Mix. Australian Maritime College, University of Tasmania. Copyright Project Website UTAS 2020: To the extent permitted by law, all www.austen.org.au rights are reserved and no part of this publication covered by copyright may be reproduced or copied in any form or by any means except with the written permission of the AMC, UTAS. Authors Other Contributors Australian Maritime College, University of Tasmania University of Queensland Irene Penesis Craig Heatherington Jean-Roch Nader Larissa Perez Philip Marsh Australian Maritime College, University of Tasmania Camille Couzi Constantin Scherelis Commonwealth Scientific and Industrial Research Christelle Auguste Organisation (CSIRO) University of New South Wales Mark Hemer Wei Shen Jenny Hayward University of Sydney Saad Sayeef Mohammad Seidaliseifabad Peter Osman Aquatera Uwe Rosebrock Gareth Davies Michael Herzfeld Schottel Hydro David Griffin Ralf Starzmann University of Queensland Orbital Marine Power Remo Cossu James Murray Alistair Grinham Nova Innovation Gavin McPherson Collaborating Partners Australian Industry Body Representative Project Lead Stephanie Thornton, Australian Ocean Energy Group Australian Maritime College, University of Tasmania Research Partners Acknowledgements CSIRO This project was supported by the Australian Renewable University of Queensland Energy Agency (ARENA) Advancing Renewables Program under agreement number G00902]. We are grateful to our Industry Partners research partners and industry participants for the Mako Tidal Turbines, Australia contributions, and those who provided suggestions and review comments to improve this report. Sabella, France SIMEC Atlantis Energy, Scotland Disclaimer International Collaborators The views expressed herein are not necessarily the views of the Australian Government, and the Australian Government Acadia University, Canada does not accept responsibility for any information or advice Bangor University, United Kingdom contained herein. Page | 3 Executive Summary and Highlights The AUSTEn project has mapped Australia’s tidal energy resource in unprecedented detail, assessed its economic feasibility and ability to contribute to the country’s future energy needs, and characterised in detail two potentially prospective tidal energy development sites to aid forthcoming developers. Project outcomes will aid the emerging tidal energy industry to develop commercial-scale tidal energy projects. Motivation Australia is home to some of the largest tides in the world. Tidal energy systems are considered to have the highest technical maturity in the ocean renewable sector and several national and international tidal energy developers have been prospectively seeking opportunities for Australian tidal energy projects. However, knowledge of Australia’s tidal resource, its spatial extent and technical implementation remain insufficient for the tidal energy industry, regulators, policy makers and research community to make any assessment of their risks for investment in potential projects. The project was established to support prospective developers, financiers, regulators and policymakers, by providing critical baseline information, and establish what contribution tidal energy could make to Australia’s future energy mix. Benefits The outcomes of this project provide considerable benefit to the emerging tidal energy industry, the strategic-level decision makers of the Australian energy sector, and the management of Australian marine resources by helping them to understand the resource, risks and opportunities available, and overcoming current barriers to investment by increasing the competitiveness of tidal energy against other forms of ocean renewables. Detailed field and numerical studies for the two sites have been delivered, providing tidal project developers a head start in commissioning their site prior to deployment of their technology. Further case studies were developed showing the potential of tidal energy in Australia’s energy mix. Beyond mapping Australia’s national tidal energy resource, outcomes from the project extend to a range of purposes for other marine stakeholders, including marine spatial planning and environmental management, marine prediction for shipping and SAR, defence, oil and gas exploration and offshore wind and wave energy. Project Participants The AUSTEn project is a collaborative effort between research partners - the Australian Maritime College at the University of Tasmania, The University of Queensland and CSIRO; Industry partners - Mako Tidal Turbines, Sabella and SIMEC Atlantis Energy; and international collaborators – Bangor University, UK and Acadia University, Canada. The project is co-funded by the Australian Renewable Energy Agency (ARENA) Advancing Renewables Program. Industrial partner involvement has brought valuable real project experience to deliver the outcomes. The broad collaborative research team has maximised domestic knowledge of both Australia’s marine estate and electrical systems and ensured strong international exposure. The project further benefitted from regular and sustained interaction with further project stakeholders (governmental bodies, regulatory bodies, grid and network experts as well as tidal and wave turbine engineering firms, developers and academia) throughout the project. Project Innovation This Australian first project consists of three inter-linked components that have delivered: • A National Australian high-resolution tidal resource assessment (~500 m resolution), feeding into the Australian Renewable Energy Mapping Infrastructure (online resource atlas). • Focused case studies at the Banks Strait, Tasmania, and the Clarence Strait, Northern Territory for energy extraction, involving field based and high-resolution numerical site assessments, as well as in-situ environmental measurements and observations. • Technological and economic feasibility assessment for tidal energy integration to Australia’s electricity infrastructure, including consideration of important issues such as grid integration, and competitiveness against existing and new sources of generation, intermittency and farm design. Case studies at six key sites also outlined opportunities for adding tidal generation to the energy mix. Page | 4 Results A newly developed national Australian unstructured high-resolution hydrodynamic tidal model has identified the spatial extent of tidally energetic sites around Australia, and significantly enhanced understanding of Australia’s national tidal stream and range energy resources. The most energetic sites are predominantly distributed across the northern shelf of Australia, particularly on the North-West shelf, with sparse distribution to the south of Australia that include Banks Strait, NE Tasmania, and Port Philip Heads, Victoria. However, the tidal velocities of order 2-2.5 m/s, are lower than seen in other parts of the world (UK, Europe, Canada and the US), where Tidal Energy Converters (TECs) currently installed are deployed in sites with flows of approximately 4 m/s. Extensive field campaigns were conducted to characterise promising sites at Banks Strait in NE Tasmania, and Clarence Strait in the Northern Territory. High-resolution numerical models of these two sites were successfully developed, calibrated and validated, with assessments of the tidal energy resource to international standards completed. These case studies located tidal velocities up to 2.8 m/s suggesting these sites are unlikely to be developed using current generation of TECs that seek flows greater than 4.0 m/s to be commercially viable. However, the moderate flows, suitable depth ranges and bottom compositions suggest these sites may be viable for TECs better suited to harnessing lower velocity flows. Although current speeds were lower than that found at promising sites internationally, for both the Banks and Clarence Strait sites, the potential area nationally for tidal turbine deployment was found to increase substantially when selecting sites with maximum flow speeds greater than 1.5 m/s, opening up new areas for potential TEC deployments. For both sites, the network capacity would need to be increased to take advantage of the substantial tidal energy resource. Using power curves from off the shelf (OTS) TECs, the extractable power was determined from the national and regional resource assessments. Estimates of extractable power were also determined using TEC power curves adjusted for local conditions (flow speeds). As the amount of electricity produced depends not only on the resource, but also on the local electricity grid, studies of the electricity infrastructure at the most energetic sites around Australia were also performed. These included sites connected to Australia’s National Electricity Market (NEM),