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Two types of wind lidar?s have become available for ground-based vertical mean wind and turbulence profiling. A continuous wave (CW) wind lidar, and a pulsed wind lidar. Although they both are build upon the same recent 1.55 μ telecom fibre technology, they possess fundamental differences between their temporal and spatial resolution capabilities. A literature review of the two lidar systems spatial and temporal resolution characteristics will be presented, and the implication for the two lidar types vertical profile measurements of mean wind and turbulence in the lower atmospheric boundary layer will be discussed.

We model the retail market with dynamic pricing as a Stackelberg game where both retailers (leaders) and flexible consumers (followers) solve an economic cost-minimization problem. The electricity retailer optimizes an economic objective over a daily horizon by setting an hourly price-sequence, which is then communicated to the end-consumers. In turn, on the basis of such price sequence, consumers optimize a utility function that accounts both for energy procurement costs and for the benefit loss resulting from deferring consumption. The game is formulated as a Mathematical Problem with Equilibrium Constraints (MPEC) and cast as a Mixed Integer Linear Program (MILP), which can be solved using off-the-shelf optimization software. In an illustrative example, we consider a retailer associated with both flexible demand and wind power production. Such an example shows the efficiency of dynamic pricing as a way to control the load for minimizing the imbalances due to wind power, assesses the overall economic results for the retailer and the consumers as well as the dynamic properties of consumer flexibility.

In food, chemical and pharmaceutical industries, regular cleaning of the equipment is required to guarantee hygienic production. Modern facilities use automated Cleaning-in-Place systems due to their reliability and reduction of manual operations. However, these systems and their cleaning routines are specially designed for each facility, equipment type and production schedule. Hence, detailed information about the energy consumption of the system is often unavailable. This work presents a method to determine the energy use of a Cleaning-in-Place system based on available data of the recorded cleaning routines. The case study was based on a heating in line, decentralised and re-use cleaning unit located in a dairy factory. The measured data of two cleaning lines of the unit was used to develop energy and mass balances in order to identify and quantify the sources and sinks of mass and thermal energy. The energy analysis showed that 68.96 MWh of steam was consumed during a period of 50 days, of which 76 % was dedicated to heating up the base solution. Besides, a total amount of 788 m3 of water was drained between the two lines, which corresponds to 20.19 MWh of thermal energy consumption. The indicators of the energy management software of the system were used to assess the method as well as the inefficiencies of the system.

In Germany, 19.6 % of the industrial final energy consumption (FEC) can be allocated to the chemical industry. Energy efficiency measures with focus on the chemical industry could thus significantly contribute to reaching the German goal of reducing greenhouse gas emissions by 80 % in 2050 compared to 1990. To achieve this ambitious goal, energy planners and industries alike require an overview of the existing energy efficiency measures, their technical potential as well as the costs for realizing this potential. Energy efficiency opportunities are commonly presented in marginal cost curves (MCCs), which rank these measures according to specific implementation costs. Existing analyses, however, often do not take uncertainties in costs and potentials into account. The aim of this paper is to create a MCC of energy efficiency measures for the chemical industry in Germany, while quantifying the uncertainties of the results and identifying the most influential input parameters. The identification of energy efficiency measures and the quantification of the associated technical potentials and costs are identified based on literature data and own assessments. Based on these findings, a cost curve is created for the current technical potential. To investigate the uncertainties of the model output, Monte Carlo (MC) simulations are performed to quantify the standard deviations of the implementation potential and costs. Furthermore, a sensitivity analysis, based on Morris Screening and a linear regression, is conducted in order to identify the most influential model input parameters.

This study investigates how pre-existing surface craters of leading edge protection coating used against rain erosion of wind turbine blades affect the maximum strains during impacts of rain droplets. Surface craters in the form of pinholes can form during the coating application process. The investigation is carried out by using finite element models of droplet impacts on surfaces with craters, where the impact velocity, droplet size, and crater position and size are varied. The simulations predict that the maximum strain is located at the crater walls and increases as the impact velocity and droplet size increase, and that craters closer to the central impact axis experience larger strains than craters placed farther away. The size of the crater was not predicted to have an influence on strains. The position of the maximum strain value was at the crater walls for all cases, and it was larger than for an impact on a flat surface. Observations from rain erosion tests suggest that some fractures initiate from pre-existing craters which act as weak points of otherwise highly resistant coatings.

existing single-family houses in the Nordic countries are to have competitive power compared to new buildings on the future housing market. Good technical solutions exist but need to be combined based on the full range of (standard) solutions in order to reach the low primary energy level of new houses. A one-stop-shop in the form of a full-service concept could be seen as a possibility to make it easy for the homeowner to comply with possible future requirements to realize far-reaching energy savings in connection with extensive renovations, provided that the building sector offers the solutions. Such one-stop-shops in the form of full-service providers of energy efficient renovation of single-family house are missing in the Nordic countries, although this service is vital to open up the market. As part of the Nordic research project `SuccesFamilies´ with the purpose to change the business environment in order to speed up the implementation of sustainable renovation of single-family houses –a sustainable renovation concept suitable for different categories of single-family houses with regard to type and age has been proposed in this article. The sustainable renovation concept includes an ideal full-service concept and technical renovation solutions targeted to different types of single-family houses.

Energy efficiency in buildings should not be reached on the expense of indoor environmental quality (IEQ). This statement is often used in connection to design and certification of sustainable buildings. The fact that it is also valid during the actual operation seems to be often forgotten. Nodaway’s energy management and operational diagnostics focus mostly on energy consumption. Consequently also present key figures comprise performance indicators related to energy use. The fact that modern buildings are not spared from IEQ related problems indicates that there is a need for joint assessment of energy and IEQ performance. The aim of this paper was to review relevant literature to form a scientific background for development of key figures enabling the joint assessment of energy and IEQ. The review resulted in forty cited publications. Majority of them focused explicitly on energy performance and indoor environment was mentioned only marginally or was not mentioned at all. We can also conclude that energy related key figures are well established and used for standard energy management as well as in different optimization algorithms involving analysis of measurements and calibrated simulations. One publication was identified that integrates thermal comfort into broader matrix of key figures. Methods for long-term evaluation of IEQ indicators suggested by standard EN 15251 seems to be usable for determination of key figures for joint assessment. Further research is needed to determine and test key figures that would directly combine performance indicators related to both energy use and IEQ.

This report investigates the impact of wind power in large power systems. The motivation for this investigation is the ever-increasing wind energy penetration into the power systems throughout the world. A generic large power system model delivered by the Danish Transmission System Operator EnergiNet.dk is used in the presented study cases.