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This report presents an analysis of sensors data leading to an initial assessment of the power performance from sea trails of the DEXA D05 Wave Energy Converter (WEC). The sea trails where performed approx. 1 nautical mile offshore from Hanstholm, Denmark during 2011. The converter was 1:5 scale model of the planned full scale DEXA WEC with a hydraulic Power Take Off (PTO). The converter had sensors to measure mooring forces, motions, as well as pressure and displacement sensors in the PTOs. The report gives the calculated power production efficiency and an analysis of the mooring forces. The DEXA D05 WEC was built, deployed and operated by the client DEXAWAVE ApS and the analysis of the sensor data, given here, has been carried out by John Lavelle under supervision by Jens Peter Kofoed in the Wave Energy Research Group at the department of Civil Engineering, Aalborg University (AAU).

This report presents the concept of ‘Dynamic Heating Accounts' in the context of social housing in Denmark.The Danish National Building Foundation has funded a project to test whether and how Dynamic Heating Accounts can be used in social housing. As part of the project, the Foundation wish to share the preliminary results with California Environmental Protection Agency, CalEPA.The report covers the principle behind, a thorough description of the methods for defining the specifications for temperature, relative humidity and CO2, as well as the framework for dividing the heating costs among the apartments.

The paper describes the first results from a large Danish project regarding measurements of energy performance and indoor environmental quality in 10 Danish Passive Houses. The project includes both qualitative and quantitative analyses. This paper describes the first results from the quantitative part.The house considered in this paper has an air change rate (ACR) of 0.34 h-1 and the results from the first few months of measurements show excellent results when relative humidity (RH) and CO2-levels are considered. When the temperatures are assessed problems with slight overheating are found. One of the main reasons for this is the low solar angles during spring combined with the lack of solar shading and a low ACR. Solar shading and increased ventilation should be able so solve the problem. The energy consumption for room heating show a very low consumption as expected whereas the energy used for heating domestic hot water is very similar to conventional houses. The paper describes the first results from a large Danish project regarding measurements of energy performance and indoor environmental quality in 10 Danish Passive Houses. The project includes both qualitative and quantitative analyses. This paper describes the first results from the quantitative part.The house considered in this paper has an air change rate (ACR) of 0.34 h-1 and the results from the first few months of measurements show excellent results when relative humidity (RH) and CO2-levels are considered. When the temperatures are assessed problems with slight overheating are found. One of the main reasons for this is the low solar angles during spring combined with the lack of solar shading and a low ACR. Solar shading and increased ventilation should be able so solve the problem. The energy consumption for room heating show a very low consumption as expected whereas the energy used for heating domestic hot water is very similar to conventional houses.

The 17 Sustainable Development Goals (SDGs) presented in the 2030 Agenda by the United Nations in 2015 provide an ambitious, global framework for sustainable development. The construction industry holds great potential for contributing to achieving the goals towards 2030. This study investigates the current state of implementation of the SDGs within the Danish construction industry, both on a strategic and project specific level. It provides insights into the barriers for implementation. A survey was distributed to actors within the construction industry and responded by 54 people, involving architects, engineers, building owners, contractors, suppliers and manufacturers, along with academic experts. The results indicate that 90% agree that the SDGs can add value to construction project, and 79% had implemented the SDGs on a strategic level. 45% had worked with the SDGs on a project level, where the goals 7 (clean and affordable energy), 12 (responsible consumption) and 13 (climate action) were most often applied. The main barriers to implementing the SDGs were a lack of measurability, time, and resources. The prioritization of goals was discussed in the light of previous research. This study provides valuable insights into the current state of implementation of the SDGs in the Danish construction industry and points towards the following directions for future research: 1) further development of tools and methods to support the actors within the construction industry, especially focusing on measurability and prioritization, 2) indepth investigation of the state of implementation of the SDGs for the different actors within the construction industry, and, lastly, 3) further studies on the challenges and barriers for implementing the goals within the construction industry.

The search for an economic means to harness energy from ocean waves continues. This paper aims to summarise the findings from our recent studies of novel wave energy devices in which flexible, deformable structures are used in place of conventional rigid structures. The devices utilise a flexible air-filled bag to capture energy from the waves and three different configurations are compared. In each of the three device configurations, expansion and contraction of the bag in waves create a reciprocating air flow via a turbine between the bag and another volume. The bags are all in the form of a fabric encased within an array of longitudinal tendons. In the first configuration, the bag is floating and ballasted such that it pierces the free surface. In the second configuration, the bag is completely submerged and connected at its top to a rigid float and at its bottom to a weight. In the third configuration, the bag is fixed at its bottom and free at the top. A series of tests at approximately 1:20 scale in the laboratory was conducted to investigate the static behaviour of the bags in still water and their dynamic response in waves. Numerical models are developed for each configuration and the predictions agree closely with measurements. Both reveal some interesting properties that are distinct from one device configuration to another.

Sustainable Development using renewable energy systems - Findings from the SDEWES 2019 International Journal of Sustainable Energy Planning and Management, Vol. 29 (2020)

Intermittence and variability of renewable resources have substantial impacts on the scheduling of energy systems. Multi carrier energy sestem concept suggests undeniable benefits to energy systems by providing the flexibility to tackle with the uncertain nature of renewable energy resources. Toward this goal, this paper aims to investigate the advantages of deploying energy storage systems in a wind integrated multi carrier energy system for investigating renewable penetration and decreasing cost operation. A linear two-stage probabilistic methodology is imploied to cover the stochastic nature of renewable and energy loads. An effective SCENRED methodology is implemented to decrease the size of the mathematical model. Finally, the results obtained from the case studies show the effectiveness of the presented system.

The use of high temperature PEM (HTPEM) fuel cells running on reformate gas shows comparable performance to HTPEM fuel cells running on pure hydrogen, even when running at high levels of CO, as long as high operating temperatures are ensured. The increased operating temperatures of these types of fuel cells offer many advantages, particularly the increased desorption rate of CO on the anode catalyst. In order to evaluate the impact of CO and CO2 on the dynamic performance of the HTPEM fuel cell, electrochemical impedance spectroscopy (EIS) has been implemented in Labview, and used on BASF Celtec P2100 fuel cells. EIS is a powerful non-invasive measurement technique, which offers more detailed information on what effects the use of reformate gas has on the performance of the fuel cell.