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Occupant controlled lighting is known to present opportunity for energy savings1,2,3,4 and can increase occupant satisfaction with the lit environment5, 6, 7, 8, 9. Scale model and Laboratory studies suggest that the illuminance interval and the starting value provided to occupants to adjust from, have an effect on the illuminance settings chosen by the occupants 10. The illuminace interval limits the possibilities of choices and the chosen illuminances tend to be distributed in all parts of the illuminance interval. This results in the mean value of illuminance settings to approach the middle of that specific interval 11,12. The starting values act as anchors for the illuminance choices, meaning that low starting values tend to result in lower illuminance settings then high starting values6, 11, 12. The influence of illuminance interval and start value is considered in this case study on occupant controlled lighting in offices with focus on energy savings and occupant satisfaction. The case study was performed in a pharmaceutical company in Måløv, Denmark where the lighting installation was renovated in a two person office and a four person office in 2013. The fluorescent tubes were replaced with DALI controllable LED luminaires and each employee was given a task light on their desk providing 592 lx, U0 = 0.5 on the task area (60 x 60 cm2) and 87 lx, U0 = 0.2 on the surrounding area, when turned on. The lluminance intervals started from zero to the maximum of 50, 100, 200 and 500 lx with U0=0.5. The starting values were the minimum and the maximum of each interval and every interval with the different starting values was presented to the occupants in a randomized order for a total of one week. The CCT was 3000 K and the illuminance settings data was monitored online by collecting the DALI signals to the LED luminairs and the use of task light was registered by continuously measuring their power consumption. The test was performed from January to March 2014 and the weather conditions were mostly overcast sky. The occupants were informed that the lighting in their offices was being tested and at the end of each week they were asked to answer an online questionnaire about their satisfaction with the office lighting. They were further notified that they, at all times, were allowed to adjust the lighting in their office to their preference. One of the two offices reported the lighting system to malfunction when the 0 – 50 lx interval was provided, they were thereby provided with an interval of 0 to 100 lx in order to support their working environment. The adjusted illuminances for the high start values were 50 lx, 100 lx, 200 lx and 455 lx for respective maximum illuminance of 50, 100, 200 and 500 lx. The low start values resulted in illuminance settings of 50 lx, 83 lx, 163 lx and 193 lx. The energy use of the LED system is compared to the previous installed power of 80W for fluorescent tubes in each office. The illuminance settings led to 80% savings for the maximum 50 lx interval, 70 % savings for the 100 lx interval, 50 % savings for the 200 lx interval and for the 500 lx interval the savings was 50 % for a low starting value but the savings were negative by 17 % when the starting value was high. The occupants of the two person office only operated the task light when the interval provided a maximum of 100 lx, starting at a low starting value. The occupants of the four person office operated the task light 65% of their working hours when provided with a low starting value and 48% of the time when provided with high starting values. The average satisfaction ratings indicated that the occupants were most satisfied with the maximum 200 lx interval; this applies for both high and a low starting value. The interval with a maximum of 500 lx provided the most satisfied occupants and the most unsatisfied occupants.The results of this case study can be used as an argument for further exploring the potential that lies within occupant controlled lighting for energy saving and occupant satisfaction as the results from the limited amount of subjects in this study support the laboratory findings for occupant controlled lighting. Low starting values within a limited illuminance interval may provide satisfied user of energy efficient occupant controlled lighting.

The world is currently facing serious problems brought about by oil dependence. Reducing oil consumption provides an opportunity to increase competitiveness, technological development, and progress. Wind energy is currently the most costcompetitive form of renewable energy, and there are strong political and industrial forces (particularly in northern Europe) supporting the development of the offshore wind industry.Offshore structures may consist of a single shallow foundation such as gravitybased platforms or multiple shallow foundations acting in concert (e.g., jack-up rigs or tension leg platforms). General loading is particularly relevant in the design of shallow foundations for offshore structures because wind, wave, and current forces produce substantial lateral load components at magnitudes that are not commonly encountered onshore.Bucket foundations were pioneered in the offshore oil and gas industry and have recently been used in offshore wind turbines. The bucket foundation is a welded steel structure consisting of a tubular center column connected to a steel bucket through flange-reinforced stiffeners.The overall aim of the research presented in this thesis was to improve the design of offshore wind turbine foundations. The work was divided into two main research efforts: geotechnical engineering experiments to gain insight into the behavior of offshore bucket foundations, and development of methods to improve the study of infiltration into unsaturated soils, an important problem in geo-environmental engineering. The outcomes of the research have the potential to directly or indirectly reduce the risks and costs related to offshore geotechnics.

Wave Dragon is a wave energy converter, which was deployed offshore at Nissum Bredning in Denmark in 2003. The experience gained from operating Wave Dragon during 2003 and 2004 has shown that the buoyancy regulation system can be improved in a number of ways. This study describes the current situation, and proposes a number of activities in order to improve the buoyancy regulation system. This work was performed under EU ENERGIE contract no. ENK5-CT-2002-00603, and is a contribution to WP 2.3/2.4 and D40/D41.

The articlw addresses an important challenge ahead the integration of the electricity generated by wave energy conversion technologies into the electric grid. Particularly, it looks into the role of wave energy within the day-ahead electricity market. For that the predictability of the theoretical power outputs of three wave energy technologies in the Danish North Sea are examined. The simultaneous and co-located forecast and buoy-measured wave parameters at Hanstholm, Denmark, during a non-consecutive autumn and winter 3-month period form the basis of the investigation.The objective of the study is to provide an indication on the accuracy of the forecast of i) wave parameters, ii) the normalised theoretical power productions from each of the selected technologies (Pelamis, Wave Dragon and Wavestar), and iii) the normalised theoretical power production of a combination of the three devices, during a very energetic time period.Results show that for the 12 to 36 hours time horizon forecast, the accuracy in the predictions (in terms of scatter index) of the significant wave height, zero crossing period and wave power are 22%, 11% and 68%, respectively; and the accuracy in the predictions of the normalised theoretical power outputs of Pelamis, Wave Dragon and Wavestar are 44%, 52% and 62%, respectively. The best compromise between forecast accuracy and mean power production results when considering the combined production of the three devices.

The paper presents the Danish case of development of wave energy devices and outlines the established best practice. A brief overview of international standardization efforts is given and the Danish involvement in this described.The developed Danish best practice, which is being carried over to the work on the international standardization efforts, involves a development divided in four phases (up to demonstration level). The methodology followed in the individual phases (with focus on the first two) is described. The main idea is that each of the phases should provide valuable information for the developers and investors, before the project is taken to the next phase. The paper presents the Danish case of development of wave energy devices and outlines the established best practice. A brief overview of international standardization efforts is given and the Danish involvement in this described.The developed Danish best practice, which is being carried over to the work on the international standardization efforts, involves a development divided in four phases (up to demonstration level). The methodology followed in the individual phases (with focus on the first two) is described. The main idea is that each of the phases should provide valuable information for the developers and investors, before the project is taken to the next phase.

This report presents the results of an experimental study that was performed on small scale model that was a replication of the full-scale Weptos WEC intended for DanWEC. During these tests, after optimising the mooring solution, various loads were measured that occur in the structure and mooring

Med den industrielle udvikling efter 1769, tidspunktet hvor James Watt tog patent på dampmaskinen, er der opstå et økonomisk, politisk, miljømæssig og energimæssig krise – hvad enten man anser denne for antagelig eller reel. Svaret på spørgsmålet ”hvordan løser man disse problemer?” er en kompliceret og ufuldendt diskussion, men med introduktionen af vedvarende energiproduktion, er der givet et bud på, hvordan man til dels kan løse disse problemer. Bølgeenergi er en uudnyttet vedvarende energikilde, som har potentiale til at bidrage betydeligt til fremtidens blandede energiforsyning. Dog har bølgeenergisektoren endnu ikke udbudt denne mulighed på markedet grundet en række tekniske og ikke-tekniske årsager. Disse kan mest effektivt opsummeres ved at på pege produktionsudgifterne som opstår ved brug af de forskellige energitransformatorer: Sammenlignet med andre vedvarende energiteknologier, er produktionsudgifterne stadigt betydeligt højere, når man udnytter energi fra havets bølger. Hvis man bliver ved denne sammenligning, er det også vigtigt at være opmærksom på, at der ikke er en klar frontløber i bølgeenergisektoren, hvilket gør at indsats og finansering spredes over et bredt felt.For at kunne bidrage til en effektiv udvikling og analyse af bølgeenergikoncepter og dermed bidrage til en acceleration af hele sektorens fremgang mod kommercialisering, er det nødvendigt med et effektivt og på lideligt wave-to-wire værktøj, som er generelt anvendeligt. En wave-to-wire model identificerer relationen mellem en energikilde på et bestemt sted og enhedens forventede produktion. Sidstnævnte er udtrykt i form af elektricitet, der leveres til elnettet. Modellen skal kunne give et groft billede af den faktiske status af sektoren og dens potentiale, og senere bruges til at finde frem til de mest lovende koncepter.På et makroniveau kan arbejdet fordeles på to hovedindsatser.Først skal komplementaritet mellem numerisk simulation og eksperimentel erfaring fremhæves, hvilket mest effektivt kan opsummeres som: Pålidelig model. Numeriske modeller er i sig selv meningsløse men lette at manipulere, hurtige og relativt billige, hvor fysiske modeller er komplekse, langsomme og dyre, men realistiske hvis implementeret i tilstrækkelig grad. Siden der ikke er et faktisk behov for ”noget nyt” men snarere ”at få det bedste ud af hvad vi har”, er den anvendte numeriske model udelukkende baseret på veletablerede metoder. Eksperimentel data bliver anvendt som verifikation til at styre retningen af den numeriske udvikling.Dernæst, kaste lys på hvad der bør være målet for sektoren: Minimering af de samlede energiomkostninger. To forskellige teknikker til at reducere omkostningerne er sammenlignet: Den første maksimerer systemomsætning (indkomst) ved at ændre på kontrolstrategien, mens den anden udvider de første metoder ved at tilføje et straf baseret på kontrolstrategiens indflydelse på det strukturelle design. Begge modeller er igen baseret på veletablerede eller standardiserede teknikker. The wild development of the world from the 1769, years in which James Watt patented his steam engine, brought utterly to the actual, real or assumed, economical, political, environmental and energetic crisis. The answer to the question “how to solve these problems?" is a tangled unsolved discussion, but talking about renewable energy partially ravels the problem out. Wave energy is a large, mostly untapped, renewable energy resource. It has the potential to contribute significantly to the future energy mix, but the sector has not yet rolled off into the market in consequence of a number of technical and non-technical issues. These can be efficiently summarised in the cost of the energy produced by the various wave energy converters: If compared with other renewable energy technologies the cost of energy from the ocean waves is still significantly higher. Holding the comparison it also important to noticed that there is not a clear front runner in the wave energy sector, which fades effort and funding over a too broad frame.In order to assist efficient development and analysis of wave energy converters and therefore to accelerate the sector progression towards commercialisation, a generally applicable, efficient and reliable wave-to-wire model tool is needed. A wave-to-wire model identifies the relation from the source of energy of a particular location to the expected device productivity. The latter being expressed in terms of electricity fed into the grid. The model needs to output a coarse picture of the actual status of the different devices and their power productivity, which is used afterwards to sieve promising concepts out.In a macro-scale the work can be divided into two main contributionsFirst, highlight the complementarity between numerical simulation and laboratory experience, in what can be efficiently summarised as: reliable model. Numerical models are per se meaningless, but easy to manipulate, fast and relatively cheap. Physical models are complex, slow and expensive but realistic if adequately implemented. Since there is no real need of “new", but more of “how can we get the best of what we have", the numerical model used is entirely based on well established methods. The experimental data is used as a check point to verify the direction of the numerical path.Second, shed light on what should be the objective of the sector: minimisation of the cost of energy. Two different techniques to reduce the cost of energy are compared: the former maximises the system revenue (income) by acting on the control logic, while the second extends the first methods adding a penalty term due to the effect of the control logic on the structural design. Both methods are once more based on well established or standard techniques.

This report presents the results of an experimental study of the wave energy converting abilities of the Langlee wave energy converter (WEC). It focused mainly on evaluating the power generating capabilities of the device, including investigations of the following issues:Scaling ratiosPTO loadingWave height and wave period dependencyOblique incoming waves and directional spreading of waves (3D waves)Damping platesMooring forces and fixed structure setupPitch, surge and heave motionDuring the study the model supplied by the client (Langlee Wave Power AS) has been heavily instrumented - up to 23 different instruments was deployed to measure and record data. Tests were performed at scales of 1:30 and 1:20 based on the realized reference wave states. This report presents the results of an experimental study of the wave energy converting abilities of the Langlee wave energy converter (WEC). It focused mainly on evaluating the power generating capabilities of the device, including investigations of the following issues:Scaling ratiosPTO loadingWave height and wave period dependencyOblique incoming waves and directional spreading of waves (3D waves)Damping platesMooring forces and fixed structure setupPitch, surge and heave motionDuring the study the model supplied by the client (Langlee Wave Power AS) has been heavily instrumented - up to 23 different instruments was deployed to measure and record data. Tests were performed at scales of 1:30 and 1:20 based on the realized reference wave states.

A test programme has been performed to determine the scour around a monopile for an offshore wind turbine. The foundation is protected against scour with a concrete plate with various designs. The tests should be regarded as pilot tests previous to a detailed investigation. The tests has been performed at Aalborg University. A test programme has been performed to determine the scour around a monopile for an offshore wind turbine. The foundation is protected against scour with a concrete plate with various designs. The tests should be regarded as pilot tests previous to a detailed investigation. The tests has been performed at Aalborg University.