OFFSHORE RENEWABLE ENERGY DEVELOPMENT OF OCEAN TECHNOLOGY PROJECTS AT INEGI

A. Barata da Rocha, F. Jorge Lino, Nuno Correia, José Carlos Matos, Miguel Marques, Tiago MoraisINEGI, Instituto de Engenharia Mecânica e Gestão Industrial

Rua Dr. Roberto Frias, 4200-465 Porto, Portugalabrocha@inegi.up.pt ; falves@fe.up.pt; ncorreira@inegi.up.pt; jmatos@inegi.up.pt; mmarques@inegi.up.pt, tmorais@inegi.up.pt

ABSTRACT

Offshore Renewable Energy is a great challenge for the future. Thermal Gradient Energy, Salinity Gradient Energy, Tidal Marine Current Energy, Tidal Energy, Ocean Wave Energy and Offshore Wind Energy can be used to produce clean en-ergy and reduce carbon emissions. This paper presents an overview of selective conversion Technologies & Demonstration Projects worldwide, as well as new concepts to be developed to assure the success of these new technologies. The first task to be performed in a project for energy conversion is to quantify the availability of the resource.

Since 1990, INEGI has evaluated wind resources in Portugal as well as many countries of Europe and South America. This experience, with more than 600 wind measurement masts installed until 2010 is now being used for the evaluation of fu-ture offshore wind and wave plants, with the use of offshore monitoring buoys.

Several research projects related to sea technology are presented in this paper, from energy production to exploration of deep sea, through the use of hyperbaric chambers developed at our Institute. The different competences needed for these projects are presented and the importance of the future of ocean energy technologies in countries with ocean resources is discussed.

Topic: Science, Ocean Technology, Engineering EducationTheme: Technology Transfer; University-Industry Partnerships

1. INTRODUCTION

1.1 RENEWABLE ENERGYRenewable sourced energy is obtained from natural re-sources such as sun, wind, rain, tides, and geothermal heat. Today, more than 20% of global final energy consumption comes from renewable. Figure 1 shows the Renewable En-ergy share of global final energy consumption in 2008 [1].

Figure 1 - Renewable Energy Share of Global Final Energy Consumption, 2008 [1].

In electricity generation, renewables have a share of around 18%, with 15% of global electricity coming from hydro-electricity and 3% from new renewables [1] [2].

Worldwide renewable energy capacity grew, during a 5 years period, between 2004 and 2009, at rates between 10 and 60% annually. Wind Power, for example, grew 32% in 2009 (see figure 2), with a worldwide installed capacity of 158 gigawatts (GW) by the end of 2009 [1].

Figure 2 - Average Annual Growth Rates of Renewable Energy Capacity, from 2004 to 2009 [1].

Renewable power capacity worldwide reached 1,230 gi-gawatts (GW) in 2009 and represents about a quarter of global power-generating capacity (estimated at 4,800 GW in 2009) and supplies 18 % of global electricity production.

Renewable energy is fundamental to solve the problems related to the intense use of fossil fuels (and its growing price), greenhouse gases, climate changes, pollution and global warming.

Most countries worldwide have, in 2010, ambitious poli-cy targets for renewable energy production, for 2010 and 2030. The 27 EU countries confirmed, in 2008, national targets for 2020, following a 2007 EU-wide target of 20 percent of final energy by 2020 (See Figure 3).

Figure 3 - Examples of national targets among EU developed countries [1].

1.2 OFFSHORE RENEWABLE ENERGYThe Ocean is one of the less explored resources of the Plan-et. It has a vast offer of natural resources to be explored, in particular energy resources of different types.

The surface of the planet is composed by 29,2% of Land and about 70,8% of Water. 97,4% of this area is salt water of the Oceans (96,5%) and Seas (0,9%). Only 2,6% of this area is freshwater [3,4]. This enormous surface receives the largest amount of energy emitted by the Sun. Solar Energy is the source of all energies leading to thermal gradients currents, winds and waves.

Oceans are important energy sources that can be converted through the use of adequate technologies: • Thermal Gradient Energy• Salinity Gradient Energy• Tidal Energy (Tidal Marine Current Energy,

Tidal Barrage Energy)• Wave Energy• Offshore Wind Energy

Wind/solar/biomass/geothermalpower generation 0.7%

Biofuels 0.6%

Biomass/solar/geothermalhot water/heating 1.4%

Hydropower 3.2%

Traditional biomass 13%

Renewables 19%

Nuclear 2.8%

1.2.1 THERMAL GRADIENT ENERGYThis form of energy conversion is obtained from the tem-perature difference between water at the surface, heated by the effect of solar radiation, and the colder water at the depths of the ocean. Ocean Thermal Energy Conversion (OTEC) can be used to generate electricity, desalinate sea water, support deep-water aquaculture, as well as aid the growth of fruit and vegetables and mineral extraction [3,5]. Due to the cost of installation, this technology is still in an early stage of development.

The temperature difference between the warm surface wa-ter and the cold deep water can reach more than 24ºC (fig-ure 4), which can produce a significant amount of power. It is estimated that the available resource is about 1013 Watts.

For countries that have a great dependence of imported fuel, and specially tropical countries, Thermal Gradient Energy has a promising future [5].

Figure 4 - World Map with temperature difference between surface and depth of 1000 meters [5].

Figure 5 shows 1 MW and 30 kW OTEC devices developed by Saga University in Japan [6].

Figure 5 – 1 MW and 30 kW OTEC demonstration devices from Saga University, Japan.

Figure 6 shows the schematic principal of an OTEC float-ing power plant [7, 8].

Figure 6 – Schema of a offshore floating OTEC power plant [7,8].

Figure 7 shows the thermal cycle and principles of an OTEC conversion system [5].

Figure 7 - Thermal cycle and principles of an OTEC conversion system [5].

1.2.2 SALINITY GRADIENT ENERGYFrom the different concentration in salinity between ocean water and rivers in places like the delta of rivers, electrical energy can be obtained from the pressure difference based on the natural phenomenon of osmosis. The salt molecules move the fresh water through semi-permeable mem-branes, causing increased pressure in a tank of salt water and therefore the flow of salt water. The flow of salt water is used to drive a turbine that produces electric power [3].

Several projects are being developed in Norway and The Netherlands based on salinity gradients. Figure 8 shows a virtual image of an osmotic power plant in Norway [9].

Figure 8 - Virtual image of an osmotic power plant in Norway [9].

From the flow of fresh water rivers into the ocean, it is estimated that in Europe, the potential osmotic energy is around 200 TWh/y [10].

Salinity gradient power tends to be a large attractive power resource, which is almost unexplored. Figure 9 shows an experimental research for osmotic salinity gradient energy conversion in Norway [6].

Figure 9 - Experimental research for osmotic salinity gradient energy conversion in Norway [6].

1.2.3 TIDAL ENERGYTidal dynamics can be used to produce energy in 2 dif-ferent manners. The first is to use local tidal currents. The second is to use the rise and fall of the sea level.

1.2.3.1 TIDAL MARINE CURRENT ENERGYCurrent is the name that designates the horizontal move-ment of water, existing in the oceans, rivers, bays and ports under the influence of tide, wind and density differences. The kinetic energy present in tidal currents can be trans-formed into electrical energy by concepts similar to those used in wind turbine, using horizontal or vertical axis turbines located at the surface, submerged or fixed to the seafloor. This type of energy, when compared with wind

energy, has a greater amount of energy due to the density of the water [3,11]. The technical tidal stream energy in Europe is estimated at about 36TWh/y, 20‐30% of known global resource [10].

The commercial exploitation of tidal marine current en-ergy needs to solve difficult problems [12] related to instal-lation, survivability and maintenance of the systems. Al-though the large amount of prototypes developed, only a few achieved a full commercial successful operation and there is still a need for further technological developments. Figure 10 [11] shows several concepts of the way to extract electrical energy from tidal current. Basically there are 3 main solutions:

- horizontal axis turbines (figure 10a)- vertical axis turbines (figure 10b)- oscilating hydrofoil (figure 10c)

Flow rotors are used to drive a generator and produce elec-tric energy. Concentrators can be used around the turbines to concentrate the flow.

c

Figure 10 – Tidal marine current energy converters (a, b, c, sea text above) [11].

a

b

1.2.3.2 TIDAL BARRAGE ENERGYTidal energy results from the rotation of the earth within the gravitational fields of the Moon and the Sun. The po-tential energy obtained by the difference in height of the tide, can be converted in energy through floating or fixed devices in estuaries or oceans. The production of electric-ity is obtained exploring the differences in water level up-stream and downstream of the dam, causing a flow of water by opening the floodgates, forced by gravity to actuate the turbine [12,13].

The world’ largest tidal barrage, the French La Rance Bar-rage (1996‐present) has 0.54 TWh/y. The planned UK Sev-ern barrage will take 10 years to build, with an estimated cost of 23 billion Euros. It could have a lifetime of over 100 years and provide 5% of UK’s present electricity demand. Figure 11 shows a worldwide view of tidal energy potential.

Figure 11. World map with tidal energy gradients [14].

1.2.4 WAVE ENERGYThe origin of this form of energy created by the effect of wind on the ocean surface is the result of the redistribution of solar radiation in the atmosphere.

Typically, the power carried by the waves is measured in kilowatts per meter of wave front (kW/m). Comparing the data of wind speed shown in Figure 12 with the annual dis-tribution of the potential energy attributed to ocean waves, Figure 13, it is observed that both figures show the highest values in the same regions of the globe, specially in both south and north Atlantic and Pacific Ocean.

Figure 12. Mean annual wind speed estimated at 50 m above sea level (between 1983-1993) [16].

Figure 13. World distribution of mean annual wave energy potential [17].

Taking as reference the latitude, it can be seen that the waves with higher power occur between the 40º and 60º for both hemispheres (North and South). Coastal areas such as West-ern Europe, North America, South America, South Africa, Australia and New Zealand are characterized by a high energy resource and therefore with favorable geographical conditions to the implementation of wave energy.

It is estimated [18] that the power resource available in sur-face waves on a global level would be approximately 10 to 10 TW for depths greater than or equal to 100 m.

In 2003, the World Energy Council estimated a value of avail-able power greater than 2TW for energy production. From the different ocean energy resources, wave energy is the largest of the sources of the oceans, and is not completely explored.

Table 1 presents the estimated available energy for produc-tion, by the different types of conversion mechanisms.

Table 1 – Estimated global resources for different technologies (TWh/year) [6,19].

Type of source Anual theoretical EnergyTemperature Gradient 10000 TWh/yearSalinity Gradient 2000 TWh/ yearTidal Marine Current +800 TWh/ yearTidal +300 TWh/ yearWaves 8000 a 80000 TWh/year

The solutions for transforming wave energy contained in the Oceans and Seas (WEC – wave energy converters), into useful energy are not recent. The first worldwide patent for the use of this energy into mechanical energy was pub-lished in 1799, Paris (France) by Girard (father and son). At the end of 1973 there were 340 registered patents. More than 200 years after the registration of the first patent for a system for converting wave energy, there are currently more than 1,000 patents with techniques for exploiting this form of energy [20].

Europe has the challenge to be the leader in develop-ing technologies for wave energy conversion, The United Kingdom is the country that most contributed to this posi-tion. Portugal has one of the first and few world wave en-ergy production units in actual production in Ilha do Pico, Azores, Portugal.

Figure 14 - OWC Pico Power Plant, Ilha do Pico, Azores, Portugal [21].

The energy of waves, given their potential energy, is re-sponsible for the largest number of projects in operation, more than 70 in all its stages, from conception to testing on the tank, with scaled models for concept testing in real en-vironment for demonstration purposes, pre-market trad-ing and finally with the construction of wind wave energy converters (see Figure 15).

Figure 15 - Number of ocean energy systems in operation per type of mechanism and stage of development [19].

Portugal is located in an oceanic region with a medium-high potential, due to its annual average wave energy of about 40 kW/m. Apart from this advantage there are other factors that classify Portugal as one of the most favorable countries for wave energy conversion, due to the weather conditions, the existence of points of connection to the network along the coast, the deeper waters near the coast, a tradition in the marine industry with good infrastructure and located near the potential local power plant farms, with two official pilot zones for wave energy testing (figure 16) [22].

Figure 16 – Portugal’s pilot zones created for wave energy testing in 2008 and Pelamis Project installed in Aguçadoura in 2009 (actually out of serv-ice due to maintenance and financial resources) [23,24].

Aguçadoura wave farm, located at the North of Portugal and composed of three Pelamis devices was the first com-mercial wave farm in the world, with an installed capacity of about 2.3 MW.

Figure 17 shows several pilot zones in Europe for activities demonstration [23,25].

Figure 17 – European infrastructures for wave energy [25].

Comparing onshore wind energy, offshore wind energy and wave energy, it can be seen (figure 18) that these technologies are at different maturity stages and not in the same state of development in all countries. Portugal is amongst the first countries to contribute to wind energy (onshore) development and is leading the development of wave energy [23].

Figure 18 – Maturity stage of different offshore and onshore energy tech-nologies in different countries [26].

Many different technologies are available and being tested, depending on the type of movement (rotational and trans-lational), on the methods of extraction of energy (hydrau-lic, mechanical, pneumatic and electric), on the location (on the coast, near the coast and away from coast) and po-sition (on land, floating and submerged).

The kinetic energy created by the movement of water mol-ecules and the potential energy created by the mass of wa-ter that is above ground level can be transformed into elec-trical energy with different methods.

Figure 19 presents different types of technologies installed worldwide for ocean tests.

Pelamis, Portugal

Limpet, UK Power Buoy, USA

Waveroller, Portugal Oyster, Scotland Wave Dragon, Denmark

AWS, Portugal FO3, Norway Oceanlinx, Australia OE Buoy, Ireland

Figure 19. Main technologies already tested at sea conditions worldwide [6,28-33].

The Pelamis project reached the most advanced status in wave energy development, through several upscales and test tanks. It is the world’s first operational wave farm, with 3 Pelamis devices, each with 750 kW and installed offshore Northern Portugal in 2009. Each device is made of 4 cylindrical segments, with an overall length of 150 m and a diameter of 3 meters, with hydraulic Power Take Off (PTO) mechanisms, installed at the interconnections. Sev-eral technical problems related to these joints forced the wave farm to stop operational tests and the complete de-vice is actually in the harbour for inspection and repairs. Presently, a Pelamis II device type is being developed, and will be installed in Scotland.

Figure 20 shows the Pelamis device in operation, the inter-connections and the operation methods.

Figure 20 – Pelamis device [27].

From the different technologies being developed, the Os-cillating Wave Surge Converter, WaveRoller, property of AW-Energy Oy, has been tested with success in central Portugal, Peniche, with a scaled 13 kW prototype, having a wing area of 15 m2, and a full scale prototype is to be tested in the coming years.

WaveRoller device is a plate anchored to the bottom of the sea. The back and forward movement of surge moves the plate. A hydraulic piston pump collects the kinetic energy transferred to this plate (figure 21).

Figure 21 – Waveroller conceptual image installed in Portugal [28].

The Oyster, figure 22, shares the concept of a wing moving within the water column, but makes use of the full depth and was designed for near shore installation, according to the manufacturer, Aquamarine Power. A prototype with a wing area of 180 m2 and 350kW of expected capacity is presently installed in Scotland, whilst an Oyster 2 is being developed [29].

Figure 22 – Oyster wave farm [29].

The Wave Dragon overtopping device elevates ocean waves to a tank above sea level where water is let out through a number of turbines and in this way transformed into elec-tricity, i.e. a three-step energy conversion [30].

Real sea tests at a scale of 1:4.5 have been performed in Denmark for more than 4 months. The arms of an operat-ing unit form a 300 meter open area that collects the water to the basin, with the turbines located more than 150 me-ters away, figure 23. Several wave dragons can be combined to operate as a wave farm.

Figure 23 – Wave Dragon prototype in sea operation [30].

Another wave technology that has been also tested in 2004 in Portugal is the 2 MW AWS MK I test platform, also at Aguçadoura. The primary extraction mechanism was test-ed together with the linear generator capability. AWS, Ar-quimedes Wave Swing, is a point absorber, harnessing the power of the wave due to the motion of a floating vertical cylinder and continues to be developed. A new AWS MK II is to be tested in Scotland [31].

Figure 24 – AWS MK I ready for departure at the Leixões harbour, Portu-gal and future AWS MK II [31].

The FO3 is a device that gathers under a floating platform a set of point absorbers of smaller dimensions. The project is based on the oil&gas technology standard platform knowl-edge and uses more advanced materials and the point ab-sorber technology to maximize the yield of the platform. The 1:3 test platform survived considerable storm condi-tions in Norway in early 2005 [32].

Figure 25 – FO3 project, wave tank tests [32].

The Oceanlinx is an Australian born technology that is a floating application of the oscillating water column princi-ple, OWC [33]. The wave motion is concentrated in a cham-ber connected to a Denniss-Auld turbine through which air is vented, with alternated flow directions due to the oscilla-tion of the water column. The turbine is specially designed to maximize power take off and to guarantee the unique di-rection of rotation, despite of the alternated airflow. Success-ful 500kW prototype was tested in 2007 (figure 26), but in May 2010, a MK3 prototype at Port Kembla’s was destroyed after breaking free from its moorings (see figure 26).

Figure 26 – Oceanlinx schema and 2007 disaster [33].

The Wavebob is a point absorber technology that takes ad-vantage of the heave motion to harness energy [34]. Next tests are scheduled for Portugal, under a FP7 financing program, and with a rated capacity over 1MW test units. Figure 27 shows the main structural components with an impressive floater tank.

Figure 27 - The Oceanbob ongoing ocean tests and harbour operations [34].

Figure 28 presents the main wave energy conversion tech-nologies presently being tested and developed, around the world [25].

Dislike the wind energy, where three bladed horizontal axis turbines are dominant, no distinctive technology is domi-nant up to now and further developments and investments are necessary to achieve one or more mature proven techno-logical solution. At the moment, as we know, no technology has achieved a commercial stage.

Figure 28 – Wave energy developments around the world [25].

1.2.5 OFFSHORE WIND ENERGYOffshore Wind Energy is a key to achieve world’s future energy demands, to avoid environmental and climate changes, to develop a new worldwide leading technology and to create a new renewable energy economy. With ade-quate political strategies, Europe has the opportunity to be a world leader in offshore wind power technology. Figure 29 displays a single row of an offshore wind farm.

technologies. Europe’s offshore wind potential is enormous and over 100 GW of offshore wind projects are currently under development.

The progress of Wind Energy in the last 10 years has been impressive. The EU had 9.6 GW of onshore installed power in 1999. By the end of 2009, 72GW were reached. Accord-ing to the European Commission’s “New Energy Policy” projections for electricity demand in 2020, wind energy would meet 16.9 % of the EU electricity demand, including 4.3 % being met by offshore wind farms.

Figure 30 displays the growth rate expected for the wind energy capacity and the growing importance of the off-shore contribution [36].

Figure 29. Example of an offshore wind farm [35].

Offshore Wind Energy is an unlimited energy resource, which, for electricity production purposes, does not emit greenhouse gases, enables reduction of fuel imports and can create thousands of new jobs in offshore advanced Figure 30. Cumulative EU wind energy capacity (1990-2020) [36].

Offshore Wind Energy production is growing consistently and reached 1471 MW in 2008 in 8 EU member states. In 2009, 2000 MW were reached and it is expected to achieve 3000 MW by the end of 2010, with 11 TWh of electric-ity production, and 0,3% of total EU electricity demand, avoiding 7 million tones of CO2 emissions. The EWEA – European Wind Energy Association has a target of 230 GW of Wind Power capacity in the EU by 2020, including 40 GW of offshore wind installed power, with an average annual market growth of 28% over the next twelve years. With this target, figure 31 [36], 148TWh of electricity would be produced in 2020, representing 4% of EU electricity de-mand. For 2030 the offshore target is of 150 GW, with an impressive annual growth of installed capacity, figures 32 and 33 [35], reflecting an annual production of electricity, reaching 580 TWh in 2030 (figures 34 and 35) [35].

Figure 31 - Wind power production in the EU (2000-2020) [36].

Figure 32 - Offshore wind energy annual and cumulative installations 2011-2020 (MW) [35].

Figure 33 - Offshore wind energy annual and cumulative installations 2021-2030 (MW) [35].

Figure 34 - Electricity production 2011-2020 (TWh) [35].

Figure 35. Electricity production 2021-2030 (TWh) [35].

Offshore Wind Potential is enormous. The winds are stronger and more constant; the turbines can generate elec-tricity 70% to 90% of the time. The available area for wind farms is much larger than in land and the wind resource is also more interesting.

However, and despite the technological advances in the re-cent years, technical, financial and political challenges are immense to achieve these targets. It is clear that despite the fundamentals of onshore and offshore wind energy con-version being similar, it is also clear that, somewhere in a near future, offshore is most likely to diverge further form onshore particularly in the wind resource evaluation meth-ods, the technology and in the installation and operation of wind turbines.

The offshore wind energy farms will go in the future beyond the classical 20:20 (20 meter depth, 20 km from shore), up to 350 m depth and up to 140Km from shore, with new technological solutions, new substructures: monopile, spar buoy, semi-submersible, etc. (figure 36), new support ships for maintenance and construction and even new offshore artificial harbours.

Figure 36 - Existing construction methods based on barges and deep wa-ter turbine development [35].

Especially for countries with steep shores and that rapidly reach depths in which existing offshore installation is not possible, offshore wind energy development will surely follow this path. Figure 37 presents some of the concepts being tested. Both Hywind and Wectop concepts have suc-cessful prototypes in sea tests, whilst the Wind Float has announced the intention to test its prototype in the north-ern part of Portugal for 2011.

Figure 37. Representative schemas of existing floating offshore wind concepts [26].

Figure 38 shows operating offshore wind farms in Europe [38].

Figure 38 - Operating offshore wind farms in Europe [37].

Just like wave energy conversion, wind turbines will also have to prove that survivability is not an issue. There are many challenges to achieve, namely much research and development to be made, but little time to meet such am-bitious targets. Very specific and clear paths and targets should be defined related to:

1.Development of an EU transnational offshore grid infra-structure, and maritime spatial planning

2.Operational programs for funding of European offshore R&D projects

3.Offshore Wind Energy Technology Development – new structures, assembly and installation, operation and

maintenance, electrical infrastructure, new offshore wind turbines (5MW), new support vessels (figure 39 and 40), etc;

4.Assessment of the Offshore Wind Resource – measure-ments, wind resource and energy yield estimates;

5.Environmental impact of Offshore Wind Energy (both lo-cal and global) – birds and fishes, impact on CO2 emissions;

6.Social and economic impact of Offshore Wind Energy (employment, new industries and further competences).

Figure 39 - New concepts for support vessels. Capacity to lift 18 3.6MW turbines in 45m depths, including seabed penetration [35].

Figure 40 - New concepts for support vessels. Multiple carrier concepts [35].

Offshore Energy is unlimited, will never become a limiting factor, and there is enough space and energy over the seas of Europe to meet Europe’s global electricity demand in the future. Special offshore energy harbours will have to be idealized in order to meet the great demands of this prom-ising future market. Figure 41 shows a futuristic offshore energy harbour, idealized by INEGI [7].

Figure 41 – Visionary concept of an offshore energy harbour. ©INEGI [7].

2. PROJECTS DEVELOPED IN INEGI

2.1 AUTONOMOUS SUBMARINE DEVELOPMENTINEGI collaborates, since 1999, in the development of au-tonomous submarines (AUVs and ROVs) with the Labora-tory for Underwater Systems and Technologies (LSTS) Insti-tute for Systems and Robotics (ISR) a research unit hosted at the University of Porto. This long term collaboration aimed at developing a family of underwater autonomous vehicles and monitoring systems. INEGI’s role is the design and de-velopment, production and integration of all mechanical and structural solutions for the vehicles, while ISR’s activ-ity is linked to the electrical and electronic systems, software and vehicle control and mission planning.

This project, which pushed INEGI’s capacities for design, prototyping, manufacturing and mechanical testing deliv-ered the first nAUV (new Autonomous Underwater Vehicle) in 2005 (figure 42) and saw, in 2006, the delivery of the first Remotely Operated underwater Vehicle (ROV).

Figure 42 - Computer illustration of the nAUV autonomous vehicle.

2.2 OCEANOGRAPHIC OBSERVATORYRAIA is the result of a common strategy developed by the re-gions of the North of Portugal and Galicia in Spain with the ambition of reaching a deeper understanding of the ocean in the northwest of the Iberian Peninsula (figure 43). Within the project, different partners with operational, technological and scientific background look at the issues of operational ocea-nography. INEGI’s role as a technology development partner is focused on innovations in marine observational buoy technol-ogy. Partners in this project: MeteoGalicia, INTECMAR, Instituto Español de Oceanografía (IEO), Instituto de In-vestigaciones Mariñas (CSIC-IIM), CETMAR, Universi-dade Vigo, Puerto de Vigo/Puertos del Estado, CIIMAR, INESC, Universidade do Porto, Instituto Hidrográfico (IH) and Universidade de Aveiro.

Figure 43 - Oceanographic buoy “A Guarda” installed in the framework of RAIA.

2.3 HYPERBARIC CHAMBER “SEAFLOOR”In 2007 INEGI completed the development and proto-typing of SEAFLOOR, a hyperbaric chamber designed to enable the laboratory replication of the environmental conditions near sea vents at depths up to 2000 m. The car-bon fibre filament wound design led to an extremely light system weighting less than one third that of conventional metal solutions and capable of withstanding service pres-sures up to 200 bar with high durability.

The equipment, which incorporates interfaces for pressure, light and fluid movement sensing, allows scientists to ob-serve the organisms’ behavior in simulated environmental conditions. SEAFLOOR is a relatively “portable” solution for hyperbaric systems for a variety of fluids and, due to its internal coating, is resistant to chemical attacks while maintaining its biocompatibility unchanged.

The hyperbaric prototype system was successfully installed in LabHorta (IMAR) and has been in continuous opera-tion since March 2007 (figure 44).

Figure 44 - The SEAFLOOR system installed in LabHorta IMAR.

2.4 INNOVATIVE PORTUGUESE SAILING SHIP “VELEIRO INOVADOR PORTUGUES - VIP”The aim of VIP is to develop and build a 33’ (10m) long innovative sailing ship, under the orientation of the ship-builder Tony Castro. The project (figure 45) is being carried out by using the engineering capacities of FEUP, AEFEUP, INEGI, APDL, and with the participation of interdiscipli-nary teams composed by students and researchers in the areas of materials, product development, numerical simu-lation and electronic sensors.

Figure 45 - Computer illustration of the VIP yacht.

2.5 DEVELOPMENT OF A WINDING SYSTEM FOR SYNTHETIC CABLE FOR OFFSHORE INDUSTRIAL APPLICATION. INEGI and TEGOPI have developed a large cable wind-ing system for the long, high strength / high modulus ca-bles used in the oil industry and deep-water explorations. These cables provide high tensile strength levels, reaching 20.000 kN. In this project INEGI developed a system to wind the cables on bobbins with 5 meters of diameter, 8 meters length, and 60 ton of weight (figure 46). This de-velopment process has integrated the entire system design, the mechanical and automation project, as well as a full in-tegration of a 1:1 scale prototype. The prototype went into continuous production at the end of 2006.

Figure 46 - Prototype winder.

2.6 CONSTRUCTION OF A TANKER SHIP PROTOTYPEIn this project INEGI designed and built a prototype tank-er ship, scale 1:100, in order to test docking conditions in a simulation water tank (at the Faculty of Engineering of the University of Porto). INEGI created the 3D model of the hull using proprietary software, based on the original drawings of an actual tanker shipyard. This design was lat-er rapid prototyped at INEGI (using LOM – Layer Object Manufacturing - capability) and the resulting model was used to build moulds and parts (figure 47).

Figure 47 - 1:100 scale tanker prototype.

2.7 WAVE ENERGY CONVERSION SYSTEMINEGI was responsible for the development of the very large shaft-bushing system which is integrated in the de-sign of the wave energy conversion project WAVE at Mar-tifer (figure 48)[38]. In this project, INEGI and Martifer implemented a full systems’ engineering approach which allowed systematic selection of candidate architectures and definition of functional requirements for system de-sign and bushing development. In parallel with the shaft-bushing design work packages, INEGI was also involved in the testing of materials, development of test systems and laboratory testing of specific subsystems.

Figure 48 - Concept model of the wave energy conversion system under development by INEGI and Martifer [38].

2.8 PRELIMINARY OFFSHORE WIND ENERGY ASSESSMENTThis project was based on a study of wind power in Portugal and aimed at rating different technologies in terms of esti-mated power output and provide an analysis of technical and environmental constraints for the installation of off-shore wind turbines. The project combined data acquired at the promoters equipments (wind turbine owners and oper-ators) with mesoscale atmospheric simulation models and allowed a preliminary assessment of wind energy resources off the coast of Portugal.

Figure 49 - Computational simulation model.

CONCLUSIONS

The future World Marine Renewable Energy sector will have to share the ocean with other activities (marine trans-portation, fishing, aquaculture, water sports, etc.).

Multi-purpose offshore platforms for marine renewable energy production seem to be the future for this sector, creating sustainable ecosystems. Most of the described off-shore energy technologies, presented in this paper, are in an early stage of development and some are far from com-mercial use. However, looking at other onshore renewable energies and their exponential growth in the last decade, it is predictable that offshore energy generation will have a tremendous growth until 2030, contributing for a world sustainable development.

INEGI has been working in renewable energies since 1990, with more than 600 meteorological stations designed for wind resource assessment purposes. More than 90% of the wind installed capacity in Portugal has been developed with INEGI’s contribution in resource availability studies, atmos-pheric flow modelling and performance analysis of installed wind farms. Portugal is one the European countries with the largest growth rates on onshore wind energy production in the last 10 years (100MW in 2000, to 3800MW in 2010). INEGI is now working in many countries in Europe, South America and Africa in this area.

INEGI is now focused on new sea opportunities for energy generation, using its vast experience of more than 20 years and recognised knowledge on renewable energies. INEGI is also actively involved in the new National Sea Cluster, Oceano XXI (www.oceano21.org), that promotes coopera-tion between companies and research centres and universi-ties, to develop a new sea economy.

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