Optimization of reliable cyclic cable layouts in offshore wind farms

A novel approach for optimizing reliable cable layouts in offshore wind farms is presented. While optimization models traditionally are designed to suggest acyclic cable routes, those developed in this work recognize that cyclic layouts reduce the consequences of cable failures. The models under study take into account that cables cannot cross each other, which, particularly in instances with restrictive cable capacity, can make it attractive to let cables follow a joint trajectory, and visit turbines without connecting to them. A two-layered optimization process is developed. The outer layer is associated with an integer programming problem, which is subject to simultaneous generation of rows and columns representing cable paths. In the inner layer, a problem identifying feasible low cost paths is solved, guided by optimal dual variable values in the continuous relaxation of the former problem. Results from experimental applications to existing wind farms show good promise of the method.publishedVersio

The Diffusion of Renewable Energy Technology : Interactions Between Utility Strategies and the Institutional Environment.

Imperial Users onl

The Yoga Analogy: Scaling-Up the U.S.’s Renewable Energy Sector Mindfully with New Technologies, Evolving Standards, Public Buy-In, Data Sharing, and Innovation Clusters

This paper focuses on innovative renewable energy devices, exploring how scientifically-based industry standards that continuously evolve with engineering design technology, the public’s buy-in and feeling of connectedness with groundbreaking devices, and innovation clusters that accelerate device development through data sharing and public-private partnerships can all help advance the U.S.’s domestic renewable energy industry. Part I analyzes challenges inherent to scaling- up novel renewable energy technologies while simultaneously developing the industry standards regulating them. Part II uses the Block Island Wind Farm, an offshore wind demonstration project, and Pavegen’s globally-deployed arrays of piezoelectric smart flooring tiles as examples illustrating the importance connectedness and engagement play in garnering public buy-in during a cutting-edge renewable energy device’s roll-out. Part III discusses private investors’ critical role in bearing financial risks associated with backing experimental technologies, promoting aesthetically unusual device designs, and integrating novel devices into the built environment. Part IV explores the advantages that data anonymization and data sharing within a data trust construct can produce for constituents in an innovation cluster, particularly those functioning together within a public-private partnership. Part V explores the benefits of introducing a renewable energy device prototype in an innovation cluster, where the government, academia, and industry collaborate and share data through public-private partnerships in an engaged, supportive, and technologically savvy community focused on accelerating the development of a particular industry. This paper concludes that by setting industry standards that continuously evolve in tandem with technologies they aim to regulate, having businesses’ investment-backed expectations remain a key driving force in renewable energy device development, and deploying government funding through innovation clusters that support data sharing and public-private partnerships in a particular industry, the U.S. can strike a desired balance and mindfully scale-up its nascent renewable energy industry

Learning, future cost and role of offshore renewable energy technologies in the North Sea energy system

The pace of cost decline of offshore renewable energy technologies significantly impacts their role in the North Sea energy transition. However, a good understanding of their remains a critical knowledge gap in the literature. Therefore, this thesis aims to quantify the future role of offshore renewables in the North Sea energy transition and assess the impact of cost development on their optimal deployments. The following findings were observed in this thesis, 1) Fixed-bottom offshore wind is well established in the North Sea region and is already competitive with onshore renewables 2) Floating wind is emerging and their current costs are high, but it can reach about 40 EUR/MWh by early 2040 and would require 44 billion EUR of learning investment.3) Grid connection costs will become a major factor as wind farm moves further away. Policy actions and innovation is needed in this space to avoid increasing integration costs. 4) Offshore wind (fixed-bottom and floating) can play a significant role in the North Sea energy system, comprising 498 GW of deployments in 2050 (222 GW of fixed-bottom and 276 GW of floating wind) and contributing up to a maximum of 51% of total power generation in the North Sea power system. 5) The role of the investigated low-TRL offshore renewables, including the tidal stream, wave technology, and bioethanol, was limited in all scenarios considered, as they remain expensive compared to other mature technologies in the system

Risk- and Reliability-Based Design Optimization in Offshore Renewable Energy Systems

Offshore wind and wave energy have the potential to be significant sources of future global electricity production, reduce carbon emissions, decrease dependence on energy importation, and stimulate economic growth in coastal and remote areas. Fixed-foundation and floating offshore wind and wave energy technologies are at different stages of development, but they all have the potential to success- fully function in the renewable energy sector if developers can provide reliable, efficient technologies that can survive their harsh environment to be economically profitable. To achieve this, developers need to consider reliability simultaneously with power production and cost early in the design process. This thesis uses risk- and reliability-based design optimization to consider reliability, cost, and performance during subcomponent, device, and system design to enable the exploration of optimal solutions in offshore wind and wave technologies. The included work advances the state-of-the-art of reliability-based design optimization (RBDO) in offshore renewable energy systems via three research foci: 1) establishing relationships between component reliability, failure costs, power production, and layout optimization of offshore wind arrays, 2) evaluating how geometry optimization of WECs affects component reliability and power production, and 3) quantifying how co-location of offshore wind turbines and wave energy converters (WECs) in the same ocean space affects power production, reliability, and cost. Through these research foci, this thesis aims to achieve the objective of improving the design and market competitiveness of offshore renewable energy systems by establishing relationships between component reliability and systems optimization and creating methods for including reliability into design at component and system levels

The Economics of Renewable Electricity Market Integration. An Empirical and Model-Based Analysis of Regulatory Frameworks and their Impacts on the Power Market

As power systems increase in complexity due to higher shares of intermitting RES-E, so increase the requirements for power system modeling. This thesis shows empirically, with examples from Germany and Texas, that the increasing RES-E share strongly affects current power market operation. The markets further create price signals, which lead to system adaptations in the long-run. To get an estimate of the adaptation effects, 'The High Temporal Resolution Electricity Market Analysis Model' (THEA) has been developed. In a first application for the ERCOT market in Texas, particular model attributes are tested and compared to some complexity reducing approaches, i.e. the reduction of temporal resolution and the reduction of operational constraints. In both cases, the results show significant differences compared to the results when the full spectrum of THEA's capabilities is utilized. The ERCOT case study additionally shows that the adaptation to RES-E in an isolated, mainly thermal-based power system is quite severe. Market signals which underline this conclusion are the severely reduced value of wind energy, the increasing curtailment and the strong shift towards peak-oriented generating capacities. The second application of THEA models the German power market with its interconnected markets. This analysis increases the complexity significantly by modeling a well interconnected system, increasing the amount of different RES-E technologies and adding CAES investment options. In order to assess the impact on the different system component's supply, demand and grid infrastructure, specific measures are applied to compare several scenarios. Each scenario represents a policy option, which either reduces or increases the flexibility of the power system. The scenario comparisons capture the effects of a lower RES-E share, a larger baseload capacity fleet, higher interconnector capacities, various RES-E support scheme designs and the capability of RES-E to participate in the reserve power market. In general, the results show that if the flexibility of one system component is reduced, the flexibility values of other system components increase, which suggests a careful, integrated and long-term oriented policy setting