Standards for marine energy move on

Extensive standardization work needed to develop marine energy sector

By Morand Fachot

Marine energy is emerging as a huge source of renewable energy but depends on disparate kinds of energies, all of which require different technologies for their full exploitation. IEC TC (Technical Committee) 114: Marine energy, prepares International Standards for this promising sector.

Hammerfest Strom HS1000 tidal
Tidal turbine array on the seabed (Artist impression)

Present everywhere but difficult to collect

Harnessing marine energy presents particular challenges, which explains why investment in this sector has been relatively modest so far compared to efforts in other renewables.

As oceans represent a huge source of power that can be partly converted into electrical power, the drive to develop existing or new technologies led to the creation of IEC TC 114 in 2007.

Its title: Marine energy – Wave, tidal and other water current converters, gives a clear indication of its scope, although the TC adds that it is open to "other conversion methods, systems and products". However, it also specifically excludes "tidal barrage and dam installations", which are covered by IEC TC 4: Hydraulic turbines. Despite this, TC 114 is also exploring the potential of exploiting river currents.

The TC 114 remit is to prepare International Standards that allow technologies developed for marine energy conversion to evolve beyond the early stage of development, where they have remained for some 30 years, to reach full commercial deployment.

Extensive assignment

To achieve this objective, TC 114 has adopted a structure that brings together, as of May 2014, 115 experts from 14 Participating countries and 9 Observer countries into 10 PTs (Project Teams) and 3 AHG (ad hoc Groups).

The TC prepares International Standards that aim to address essential aspects of marine energy conversion, including:

  • system definition
  • design requirements performance
  • measurement of wave, tidal and water current energy converters
  • resource assessment requirements, design and survivability
  • safety requirements
  • power quality
  • manufacturing and factory testing
  • evaluation and mitigation of environmental impacts

The TC has published 3 TS (Technical Specifications) that cover terminology and power performance assessment of wave and tidal energy converters. More are due to be released in the coming months.

Its current work programme includes the preparation of publications providing a Guideline for design assessment of OTEC (Ocean Thermal Energy Conversion) and the assessment of mooring systems for marine energy converters as well as for wave and tidal energy resource assessment and characterization. TC 114 is also working on power performance assessment for electricity-producing river energy converters.

From research to full-scale deployment

As marine energy conversion projects are gradually shifting from research and prototype schemes to grid-connected commercial deployments, the need for standardization is obvious. International Standards will help reduce the technical and financial risks associated with the wide range of new technologies and enable a quicker adoption of marine energy conversion.

To prepare these Standards, TC 114 has set up PTs for design, device performance and resources assessment. It has also set up a PT for electrical power quality requirement issues to address grid connection and integration, and a PT to move forward on OTEC.

TC 114 is now dealing with the full spectrum of technical issues from scale testing to grid integration.

Since marine energy projects share some technical issues with offshore wind farms on common elements, such as mooring and floating installations, TC 114 is liaising with TC 88: Wind turbines.

Conformity assessment needs

The IEC's CAB (Conformity Assessment Board) set up WG (Working Group) 15 to develop a Framework for an internationally standardized approach to addressing the conformity assessment needs of the marine energy industry.

At its June 2013 meeting, CAB decided to establish a 4th CA (Conformity Assessment) system, known as IECRE, to manage CA schemes for wind energy, marine energy and solar PV (photovoltaic energy) and, eventually, for other RE technologies, such as solar thermal electric plants and fuel cells. A proposal for approval of the IECRE CA system will be submitted to CAB in June 2014.

Obvious customers for TC 114 Standards are the industry (device and project developers and manufacturers), test centres, certifying bodies and regulators, national and local authorities and potential investors.

Considering the publications already issued and the projects that either have been launched already or are near completion, it is safe to assume that TC 114 work will give the marine energy industry and utilities all the Standards they need to manufacture and deploy the best possible systems.

Hammerfest Strom HS1000 tidal Tidal turbine array on the seabed (Artist impression)
image_37_7078 The Pelamis offshore wave energy converter uses the motion of waves to generate electricity (Photo: Pelamis Wave Power Ltd)
The-huge-turbine-and-base-prior-to-subsea-installation Atlantis AK 1000 tidal turbine waiting to be lowered onto the seabed (Photo: Atlantis Resources Ltd)