Final Report Summary - WAVEGEN (Wave pump submergible power generator) The energy sector is going through a renovating process, which sees its opening towards renewable energies; it's in the dynamic evolution of this emerging industry that a wave energy sector is emerging. Although the technology is relatively new and currently not economically competitive with more mature technologies such as wind and solar energy, the interest from governments and industry is steadily increasing.Wave energy, in fact, is an abundant renewable resource, which is starting to be exploited by several European countries and considerable progress has been made over the past decade in this sector in Europe, resulting in some technologies being at, or near, commercialisation. From this perspective, WAVEGEN represents an innovative step forward in the pursuit of reliable, economic and sustainable energy devices. The WAVEGEN project proposes to investigate the integration of the Wavepump, a proof of concept lightweight offshore wave energy converter, with a submergible hydraulic turbine, finalised at the development of a novel concept of submerged offshore wave energy converter, allowing direct conversion of wave energy into electrical energy. The integration of the two technologies is extremely appealing and highly innovative, and has the potential to provide real sustainability to small wave energy applications, representing a potential breakthrough in the wave energy sector:- The Wavepump has already proved its operation through several tests as a stand-alone single device, providing exceptional results as far as yearly production and reduced installation costs are concerned and requires to be improved and developed in a cluster configuration, to provide steady and constant water flow.- Submergible hydraulic turbines are now entering the market, and allow innovative implementations never achieved so far.There is a sensible amount of scientific and technical knowledge which requires to be generated in order to provide successful application to this approach, which is definitely all but a mere design of a simple integration.Project objectives can be summarised as follows:- Provide in depth analysis of the WAVEGEN concept, by:a) study clustering of Wavepumps and model optimised integration of multiple Wavepump energy convertersb) modelling fluid dynamic phenomena occurring in such a system, and implementing a complete computational fluid dynamic (CFD) parametric simulatorc) performing virtual optimisation through the integration of the CFD model with the experimental design (ED) methodology, finalised at the achievement of the most efficient and constructive flow from the pumps into the turbine, maximising energy output, water turbine coupling and minimising fatigue stress over the structure.- Derive from the knowledge base generated through such a virtual optimisation approach, replicable criteria allowing the design of a modular multi-pump system in variety of sea conditions and sea wave energy spectra; a sitting tool will be made available, based on the exploitation of the knowledge generated during the ED driven optimisation of the CFD parametric model.- Develop and implement the best integration of the Wavepump with the submergible hydraulic turbine; this will involve:a) dumping vibrations derived from oscillating water flows and consequently provide proper specifications of plastic and metallic materialsb) ensuring constructive and non destructive interactions among the flows coming from different pumps, improving conversion efficiencyc) revising accordingly all accessories (like valves).- Develop the WAVEGEN system in order to:a) reduce the need of maintenanceb) secure a power plant extended production timec) improve the total effectd) reduce the risk of breakdowne) reduced-cost production of cables, construction and laying offshore. - To be the most economical plant installation criteria were:a) yearly production / installed capacity - target: highest values in the businessb) installed cost / yearly production target: lowest value in the business. - To perform and document a series of testing, to assure the reliability of the WAVEGEN prototype. - To decrease the cost below 2USD / W and 5 p / kWh. The leading shove for this project was the search for a cost effective and reliable product able to open the wave energy market and make it grow into a profitable opportunity. WAVEGEN proposed to develop a modular, very low impact, off-shore wave energy converter, exploiting the above mentioned technology as well as an analytical approach (by fluid dynamic simulation and experimental design optimisation) to the design of the array of pumps.By the end of the project, WAVEGEN was to deliver the following demonstration prototype:- 100 kW offshore submerged wave energy converter- linear array made of 5 Wavepump units made of standard polyethylene pipes, each approximately of the following size:a) buoy diameter 3 mb) buoy height 1 mc) pump cylinder diameter 0.7 m, length 6 m- piston rod diameter 0.2 m, length 15 m pumps producing flow in a main pipe leading to the sub-sea energy converter, all installed in a common anchoring platform.- The total length of the platform is defined by half a wavelength - 15 to 20 m.- The distance between the pumps eliminates pulsation in the main pipe leading to the energy converter.- Installation depth around 20 m.- The five pumps will deliver 350 l / sec at 4 kg pressure (100 kw) when working in the average wave regime at Madeira.- Pumps producing flow in a main pipe leading to the sub-sea energy converter, all installed in a common anchoring platform.The system will allow easy clustering into arrays and delivery of flow from a number of pumps into a common sub-sea power generator, or traditional onshore hydropower converter; if the pumps are installed in a strategic distance in the wave amplitude, the pulsating flow to the converter is eliminated. 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