Offshore Renewable Energy Deployment
Submitting InstitutionManchester Metropolitan University
Unit of AssessmentEarth Systems and Environmental Sciences
Summary Impact TypeEnvironmental
Research Subject Area(s)
Earth Sciences: Oceanography
Engineering: Maritime Engineering, Interdisciplinary Engineering
Summary of the impact
Examples are provided of significant impact by the Centre for
Mathematical Modelling and Flow Analysis (CMMFA) upon the Marine
Renewables and Offshore Wind communities. In particular, CMMFA informed
the design of a novel wave energy converter being commercialised for
connection to the national grid. CMMFA has also contributed to a study of
the design parameters for an offshore wind power station as part of a
larger interdisciplinary collaborative research effort. This work responds
to and informs the RCUK
Energy Programme via underpinning research, capacity building and
provision of trained personnel thus enacting UK Government Energy Policy.
The context for the Impact case study is the UK Department of Energy and
Climate Change 2007 Energy White Paper and its UK Renewable Energy Roadmap
and 2012 update. These documents set out the UK Government policy and
target to deliver 15% of UK energy from renewables by 2020. Eight
technology areas are identified: onshore wind, offshore wind, marine
energy, biomass electricity, biomass heat, ground/air source heat pumps
and renewable transport. Responsibility for delivering the technology
rests in part with the RCUK Energy Programme, which, through its funded
programmes, seeks to position the UK to meet its energy and environmental
targets and policy goals through world-class research with impact,
capacity building and training. The RCUK programme, with £625M invested
thus far, is helping the UK to make evidence-based policy decisions on
energy addressing the climate change agenda, including changes to
regulatory mechanisms and impact assessments. CMMFA's research and Impact
case study is linked to 2 of the above 8 technology areas, namely marine
energy and offshore wind.
Active in the area of free surface hydrodynamics since 1995, CMMFA has
developed in-house advanced computational fluid dynamics (CFD) models and
software. The work cited relates to the environmental impact assessment
arising from climate change, sea level rise and increased storm activity
in the offshore environment. This has critical implications for the safe
deployment and survivability of past, existing and proposed offshore
structures for both wind and wave power, which in deep water are
increasingly likely to be novel floating structures. The design and
survivability of these structures depends critically on the reliability of
hydrodynamic impact load predictions. These are a key component of a fully
integrated design solution for offshore marine structures involving other
disciplines such as electrical power engineering, materials science, rotor
aerodynamics and condition monitoring as well as environmental impact,
regulatory and socio-economic issues.
Supported by experimental studies conducted in collaborating partner
laboratories at Bath, Edinburgh, Hull, Lancaster, Manchester, Oxford,
Plymouth and Queen's Belfast universities, work was focused upon
constructing a detailed, validated, computational model in the form of a
so-called numerical wave tank (NWT). This simulates both laboratory-scale
and full-scale devices in realistic wave climates and led to the
development of the CMMFA's AMAZON suite of flow codes. CMMFA brought novel
developments in numerical techniques over the discipline boundary from its
pre-1995 work in aeronautical CFD. CMMFA pioneered their use in the sister
discipline of hydrodynamics. These included optimized adaptive mesh
generation that preserves the favourable properties and simplicity of
rectangular grids whilst combining these with so-called cut (trimmed)
cells  that align with stationary irregular boundaries/terrain,
or objects moving with up to six degrees of freedom (DoF); and,
Riemann-based flow solvers that provide high resolution of cell-interface
fluxes . The suite of codes developed included i) a numerical
wave flume based on the shallow water equations (a depth-integrated form
of the Navier-Stokes equations) suitable for calculating wave run-up in
near-shore regions  and, ii) a 3D NWT based on a full two-fluid
viscous Navier-Stokes solution in both air and water regions above and
below the free (water) surface. This can model wave generation,
steepening, overturning and breaking over a structure [4, 5]. In
the NWT, numerical wave paddles move, either singly or in groups, to
generate the required wave characteristics, e.g. directionally focussed
waves. Boundary conditions eliminate reflections or allow waves to pass
through. Outputs are a full set of flow variables e.g. pressure and
velocity fields, water surface elevations, forces and body motion
response. These supplement laboratory experiments and prototype testing.
The result is a fully detailed flow model incorporating all relevant
physics above and below the water surface. This includes the fluids, air
and water, aeration as waves break and impact a structure, wind effects on
waves and the motion response of the structure. In contrast
contemporaneous diffraction models and potential flow codes were not
suitable for breaking waves whilst previous NWTs based on the full
Navier-Stokes equations did not include compressible phenomena such as
aeration and cavitation. This may be important in quantifying loadings
under extreme wave conditions in which structures must survive .
Since 1999, the group's work in the hydrodynamics area has been funded
continuously by the EPSRC via 12 research grants and two Joule Centre
grants, (total > £10M). Seven of these are within the current REF
period (four are current). The majority of awards involve collaboration
with leading laboratory-based groups (as stated above) or are
multi-disciplinary consortium-led collaborations, e.g. with project
partners in the EPSRC SUPERGEN
programmes. The group has produced over 60 peer-reviewed publications in
the underpinning area.
Key CMMFA Researchers Professor Derek Causon, 1986 — present.
Professor Clive Mingham, 1989 — present
References to the research
 Causon DM, Ingram DM and Mingham CG (2001). A Cartesian Cut
Cell Method for Shallow Water Flows with Moving Boundaries. Advances
in Water Resources. 24:899-911. DOI:
10.1016/S0309-1708(01)00010-0, (48 citations)
 Mingham CG and Causon DM (1998). A High Resolution Finite
Volume Method for the Shallow Water Equations. Journal of Hydraulic
Engineering. 124(6):605-614. DOI:
10.1061/(ASCE)0733-9429(1998)124:6(605), (137 citations)
 Hu K, Mingham CG, Causon DM, (2000). Numerical simulation of
wave overtopping of coastal structures using the non-linear shallow water
equations. Coastal Engineering 41(4):433-465. DOI:
10.1016/S0378-3839(00)00040-5, (113 citations)
 Qian L, Causon DM, Mingham CG and Ingram DM (2006). A
Free-Surface Capturing Method for Two Fluid Flows with Moving Bodies. Proceedings
of the Royal Society of London: A 462 (2065):21-42. DOI:
10.1098/rspa.2005.1528, (47 citations)
 Hu ZZ, Causon DM, Mingham CG and Qian L (2011). Numerical
Simulation of Floating Bodies in Extreme Free Surface Waves. Natural
Hazards and Earth Systems Science 11(2): 519-527. DOI:
10.5194/nhess-11-519-2011, (2 citations)
 Causon DM and Mingham CG (2013). Finite Volume Simulation of
Unsteady Shock-Cavitation in Compressible Water. International Journal
of Numerical Methods in Fluids. 72(6): 632-649.
1) EPSRC GR/M42428: Impulsive Wave Overtopping of Seawalls and Related
Coastal Structures - Numerical Simulation: 05/99 - 09/02. £168,385. PI:
2) EPSRC GR/N24162: Numerical Prediction of Multi-Component Fluid Systems
Using a Cartesian Cut Cell Method: 02/01 - 01/03. £78,190. PI: Causon.
3) EPSRC GR/S12333: An Experimental and Numerical Study of Oscillating
Wave Surge Converters (OWSC's): 01/03 - 12/05. £120,377. PI: Mingham.
4) EPSRC GR/S23827: Violent Waves at the Coast- Are we safe at the
seaside? (Public Engagement): 04/03 - 10/05. £41,412. PI: Causon.
5) EPSRC GR/T18622: Free Surface Simulation of Wave Overtopping during
Storms: 04/05 - 03/07. £92,296. CI: Causon.
6) EPSRC EP/D077621: Extreme Wave Loading on Offshore Wave Energy Devices
Using CFD: A Hierarchical Team Approach: 02/07 - 01/10. £116,530. PI:
7) EPSRC EP/D034566: Supergen Wind Energy Technologies Phase 1: 03/06 -
03/10. £2,552,788. PI: Mingham.
8) EPSRC EP/F069162: A Hybrid Turbulence Approach for Simulation of
Breaking Waves and Their Impacts on Coastal Structures: 01/09 - 7/11.
£223,956. PI: Qian.
9) EPSRC EP/H018662: SUPERGEN WIND ENERGY TECHNOLOGIES-CORE, Towards the
Offshore Wind Power Station: 03/10 - 03/14. £4,834,191. PI: Mingham.
10) EPSRC EP/J010197: SUPERGEN MARINE: Modelling Marine Renewable Energy
Devices; Designing for Survivability: 6/12 - 6/15. £1,039,617. PI: Causon.
11) EPSRC EP/J012793: FROTH: Fundamentals and Reliability of Offshore
Structure Hydrodynamics: 11/12 - 10/15. £241,712. PI: Causon.
12) EPSRC EP/K037889: Virtual Wave Structure Interaction (WSI) Simulation
Environment: 5/13 - 4/16. £323,344. PI: Causon.
13) Joule Centre F-60024: A Numerical Study of a Novel Wave Energy
Converter (Neptune): 03/07 - 02/08. £99,000. PI: Mingham.
14) Joule Centre F-60042: A Joint Numerical and Experimental Study of a
Surging Point Absorber Wave Energy Converter (WRASPA): 04/08 - 03/09.
£105,000. PI: Mingham.
Details of the impact
1) Marine Energy
On EPSRC grants GR/S12333 and GR/S12326 CMMFA and project partners,
Queen's University Belfast (QUB) carried out a linked experimental and
numerical study of Oscillating Wave Surge Converters (OWSCs). The Marine
Renewables Energy Group at QUB are acknowledged world-leading device
developers within the wave energy community credited with the development
and installation of LIMPET,
the world's first grid-connected wave energy converter (WEC). The OWSC was
a novel hybrid of the LIMPET oscillating water column device and a
pendulor-type system with a hinged paddle surge converter. The work
involved wave tank tests at QUB and numerical modelling with CMMFA's
AMAZON suite of codes to extensively map the parameter space of the
device. This enabled particular parameters such as the hinge point
location and position of an inclined back plane to be isolated, studied in
detail and revised. The models allowed realistic scenarios to be explored
to provide device productivity results. The impact was design guidance
for OWSC devices and the OYSTER WEC was developed as a direct result of
this project [A].
Subsequently, Aquamarine Power plc with a team of 45 people was formed in
2005 to bring the OYSTER technology to the commercial market [B].
Since 2010, two full-scale prototypes of OYSTER
800 have been built and tested. In May 2013, the Scottish Government
granted a license for Aquamarine Power plc to develop the world's largest
grid-connected commercial wave power array deploying around 50 OYSTER
devices with a combined capacity to power almost 30,000 homes [C].
In 2012, RCUK cited OYSTER as one of its Impact exemplars of UK energy
research and capacity building [D].
2) Offshore Wind
The CMMFA was Co-Investigator on the Phase 2 EPSRC SUPERGEN WIND ENERGY
TECHNOLOGIES-CORE Consortium project EP/H018662, `Towards the Offshore
Wind Power Station' [2010-2014]. This involved 26 academic and 7
industrial partners undertaking research to achieve an integrated, cost
effective, reliable and available Offshore Wind Power Station. CMMFA was
also a Co-Investigator on Phase 1 of the SUPERGEN WIND Energy Technologies
Consortium project EP/D034566 [2006-2010]. The focus of the SUPERGEN WIND
project was on the technological challenges related to the exploitation of
the UK's extensive offshore wind refsource through interdisciplinary
research consisting of all relevant branches of engineering embracing
environmental impact, socio-economic and regulatory aspects. In
particular, this included electrical power engineering; condition
monitoring; use of innovative materials and active load reduction; rotor
aerodynamics; lighting and radar visibility; subsea foundations and
hydrodynamics. The project had 2 parallel themes. The first dealt with the
underlying physics and engineering of the offshore wind turbine farm
whilst the second looked specifically at the wind turbine itself, building
upon SUPERGEN Phase 1. The results of the two themes are now feeding into
a third Gathering Theme, which is developing the wind farm as an offshore
power station. Development focuses upon how the station should be
designed, operated and maintained for optimum reliability. It also
considers what form future developments should take such as the up-scaled
facilities on novel floating structures and the economics associated with
CMMFA was the only UK CFD group involved as Investigators in SUPERGEN
WIND Phases 1, 2 with sole project responsibility for the subsea
foundations and hydrodynamics areas. Working with partners at Lancaster
and Hull universities, it combined numerical modelling with laboratory
studies of foundation scour at wind turbine mounts and wave loading on
fixed and floating mounts. Knowledge transfer (KT) in SUPERGEN WIND Phase
1 and 2 occurs outside of the traditional dissemination routes of academic
publications. In SUPERGEN WIND KT occurs through i) formal Consortium
Management Group Meetings, which are attended by all academic partners and
the 7 industrial project partners (e.g. E.ON plc, GL Garrad Hassan,
Alstrom Grid Ltd) [E], ii) Research Monographs targeted at
knowledge transfer to industry [F] and iii) development of future
industrial energy leaders through EPSRC Doctoral Training Centres (DTCs).
These DTCs are part-funded by industrial partners who are also involved in
project selection, placement and recruitment of doctoral students [G].
Knowledge transfer also occurs via the SUPERGEN WIND Annual Assembles [H]
at which CMMFA have presented their research. Annual Assemblies are
attended by over 50 industrial players in the wind energy sector and EPSRC
Programme Managers and Policy Makers, who set and revise the agenda for
the RCUK Energy programme. CMMFA were invited participants at the January
2013 Wind Energy Scoping Workshop convened by EPSRC [I]. This
workshop defined the research areas to be prioritised for funding in Phase
3 of the 5-year programme from 2015, leading to the current Call for
Proposals under SUPERGEN WIND. The new areas in Phase 3 include further
work proposed by CMMFA on improved and adventurous foundation concepts to
increase understanding of the dynamics of floating platforms in deeper
water underpinned by the work carried out by CMMFA and partners in Phase 2
of the programme. CMMFA is the only UK university research group involved
as investigators and project partners in both SUPERGEN WIND and SUPERGEN
MARINE [J] programmes.
Sources to corroborate the impact
[A] Text attributed to EPSRC Grant EP/K041010: Pathways to Impact,
page 1. [Confidential Source: available].
[B] Source: Aquamarine Power plc website: http://www.aquamarinepower.com/about-us/
[C] Source: BBC News Scotland Business: Ministers approve plans
for world's biggest wave farm in Western Isles:
[D] Source: Research Councils RCUK: Impact of energy research and
capacity building. New technology will the harness power of the sea:
[E] The SUPERGEN Wind Energy Technology web site provides details
of project academic and industrial partners: http://www.supergen-wind.org.uk/partners.html
[F] The cited knowledge transfer Research Monograph can be found
via the link:
[G] Details of the cited current Doctoral Training Centre can be
found via the link at the Impact of RCUK Energy Programme `Impact of
energy research and capacity building' site:
[H] The programme for the most recent SUPERGEN Wind Phase 2 - 3rd
General Assembly can be found via the link: http://www.supergen-wind.org.uk/assembly2013.html
Other General Assembly meetings, Events; publications; project
information; details of Consortium Management Group Meetings can be found
at the Supergen Wind Energy Technologies Consortium main project web site:
Copies of industrial dissemination and presentations can be found via the
Downloads link. [Accessed: 20-11-13].
[I] Details of the EPSRC Wind Energy scoping workshop held on 18
April 2013 that defines Phase 3 and subsequent Call for Proposals for
SUPERGEN WIND Phase 3 [2015-2020]: http://www.epsrc.ac.uk/SiteCollectionDocuments/Calls/2013/SUPERGENWindHubCallDocument.pdf
[J] The SUPERGEN Marine Energy Research Consortium web site: http://www.supergen-marine.org.uk/drupal/
provides full details of the funded projects; academic partners;
industrial partners; Consortium Management meetings, Grand Challenge
projects and Annual Assembles. [Accessed: 20-11-13].