MWH’s Laurie Gardiner and Emily Rudkin reflect on the latest developments in marine energy following the recent AWATEA Conference.
The potential for using marine energy in New Zealand seems good.The west and south coast’s offer significant options for wave energy and there are also areas where tidal generation could occur. However, the issue for marine energy has always been whether it is commercially viable. Overseas marine energy projects are being developed with a number already on line, while in New Zealand marine energy has until recently only been a concept.
But, with the recent AWATEA (Aotearoa Wave and Tidal Energy Association) Conference and the granting of resource consent for Crest Energy’s development in Kaipara Harbour, the business of marine energy is starting to be seriously discussed. In the future we can reasonably expect to see a number of full-scale marine energy devices in our waters, and as the costs reduce in line with technology developments it is possible that marine energy may make a valuable contribution to New Zealand’s future energy mix. This point was made by several overseas speakers at the conference who view New Zealand as having a world-class tidal and wave energy resource and being well positioned for a test facility that could attract commercial organisations in Asia-Pacific countries interested in investing in the expanding marine energy technology sector.
Aside from the staged 200 MW development in Kaipara, several other marine energy schemes are currently under development. On the Chatham Islands, the CHIME wave energy project is using Wavegen OWT (oscillating water column) technology, which was developed and has been successfully used in Scotland, while in Wellington a resource consent has been granted for a locally developed 1:2 scale wave energy device to be tested on the South Coast near Moa Point. Several other developments at both a small and large scale are also on the drawing board, and a marine energy testing facility has been proposed in Wellington.
During his keynote speech to the conference, Wayne Mapp, Minister of Science and Innovation, stated he was keen to advance a Marine Energy Centre in Wellington as a twin to the established leading-edge EMEC facility in the Orkneys. This sentiment was echoed by Richard Morris, Commercial Director of EMEC, who is hoping for a close relationship between EMEC and the NZ MEC when this eventuates.
Overseas, marine energy projects receive significant subsidies to encourage the development and implementation of the technology. In New Zealand where there is very little or no subsidy, the projects that succeed are those where marine renewables is cost comparative with other sources. While developments in New Zealand are of interest, the real benefit to be gained from energising the Pacific may be for the Pacific Island nations which are largely dependent on diesel generation. It is estimated that the cost of the diesel required each day in the Pacific – around 40,000 barrels – is about $6 million. The cost of diesel in these island states ranges from NZ$1 to $2.50 per kwh and compares favourably with the 15-25c/kwh for wave energy. Clearly, marine energy has great potential in the area but will need to progress to second and possibly third generation commercial devices in order to gain the efficiencies needed to compete with other renewable energy sources.
Through its NZAID programme, MFAT is looking to develop sustainable power generation projects to address the health and economic needs of the small Pacific Island nations – this may include marine energy projects at a later stage, although currently the technology is still at a developing stage and at a cost disadvantage when competing with wind and solar energy.
Prior to joining MWH, Emily has been involved in the development of tidal energy technology and in the feasibility assessment and development of marine energy projects in the UK. More recently, Emily has been on the assessor panel for the last two rounds of New Zealand’s Marine Energy Deployment Fund.
For more information contact Emily Rudkin,Renewable Energy Specialist based in Christchurch, Ph 03 343 8782 or email emily.j.rudkin@mwhglobal.com or Laurie Gardiner, Principal Consultant based in Wellington, Ph 04 381 5712 or email laurie.r.gardiner@mwhglobal.com
