Failure mode identification and end of life scenarios of offshore wind turbines: a review

In 2007, the EU established challenging goals for all Member States with the aim of obtaining 20% of their energy consumption from renewables, and offshore wind is expected to be among the renewable energy sources contributing highly towards achieving this target. Currently wind turbines are designed for a 25-year service life with the possibility of operational extension. Extending their efficient operation and increasing the overall electricity production will significantly increase the return on investment (ROI) and decrease the levelized cost of electricity (LCOE), considering that Capital Expenditure (CAPEX) will be distributed over a larger production output. The aim of this paper is to perform a detailed failure mode identification throughout the service life of offshore wind turbines and review the three most relevant end of life (EOL) scenarios: life extension, repowering and decommissioning. Life extension is considered the most desirable EOL scenario due to its profitability. It is believed that combining good inspection, operations and maintenance (O&M) strategies with the most up to date structural health monitoring and condition monitoring systems for detecting previously identified failure modes, will make life extension feasible. Nevertheless, for the cases where it is not feasible, other options such as repowering or decommissioning must be explored

Job Jolt: The Economic Impacts of Repowering the Midwest:

Implementing the Repowering the Midwest Clean Energy Development Plan would create more than 200,000 new jobs across the 10-state Midwest region by 2020, up to $5.5 billion in additional worker income, and up to$20 billion in increased economic activity. Repowering the Midwest's Clean Energy Development Plan promotes modern, energy efficient technologies and development of renewable energy resources, especially wind power and biomass energy. This plan contrasts with a business-as-usual scenario, which relies almost entirely on polluting coal and nuclear power plants for electricty generation. This huge resulting Job Jolt is the central finding of a comprehensive study of the economic impacts of phasing in more clean energy efficient technologies and renewable energy development across the Midwest and Great Plains. The Regional Economics Applications Laboratory (REAL), a nationally renowned research center of the University of Illinois, used its modeling techniques to determine the economic impacts of implementing the clean energy development plan proposed by the Environmental Law & Policy Center (ELPC) and its Midwest partners

Spatial Dependence in Wind and Optimal Wind Power Allocation: A Copula Based Analysis

The investment decision on the placement of wind turbines is, neglecting legal formalities, mainly driven by the aim to maximize the expected annual energy production of single turbines. The result is a concentration of wind farms at locations with high average wind speed. While this strategy may be optimal for single investors maximizing their own return on investment, the resulting overall allocation of wind turbines may be unfavorable for energy suppliers and the economy because of large fluctuations in the overall wind power output. This paper investigates to what extent optimal allocation of wind farms in Germany can reduce these fluctuations. We analyze stochastic dependencies of wind speed for a large data set of German on- and offshore weather stations and find that these dependencies turn out to be highly nonlinear but constant over time. Using copula theory we determine the value at risk of energy production for given allocation sets of wind farms and derive optimal allocation plans. We find that the optimized allocation of wind farms may substantially stabilize the overall wind energy supply on daily as well as hourly frequency.Wind power; Vine copula; Optimal turbine allocation

Solar thermal power storage applications lead laboratory overview

The implementation of the applications elements of the thermal energy storage for Solar Thermal Applications program is described. The program includes the accelerated development of thermal storage technologies matched to solar thermal power system requirements and scheduled milestones. The program concentrates on storage development in the FY80 to 85 time period with emphasis on the more near-term solar thermal power system application

Analysis of Renewable Energy Policies Related to Repowering the Wind Energy Sector: the Spanish Case

In countries that started early with wind energy, the old wind turbines were located in places where the wind is often very good. Since the best places in which the wind is concerned are occupied by old wind turbines (with lower capacity than the more recent ones) the trend is to start replacing old turbines with new ones. With repowering, the first generation of wind turbines can be replaced by modern multi-megawatt wind turbines. The aim of this article is to analyze energy policies in the Spanish energy sector in the repowering of wind farms from the viewpoint of the current situation of the wind energy sector. The approach presented in this article is meant to explain what have been the policies related to the repowering sector making a brief analysis of the spectrum of different stimulii that are demanded by the market analyzing also the future perspectives of the repowering sector by establishing the new opportunities based on the new published regulations

Performance Comparison on Repowering of a Steam Power Plant with Gas Turbines and Solid Oxide Fuel Cells

Repowering is a process for transforming an old power plant for greater capacity and/or higher efficiency. As a consequence, the repowered plant is characterized by higher power output and less specific CO2 emissions. Usually, repowering is performed by adding one or more gas turbines into an existing steam cycle which was built decades ago. Thus, traditional repowering results in combined cycles (CC). High temperature fuel cells (such as solid oxide fuel cell (SOFC)) could also be used as a topping cycle, achieving even higher global plant efficiency and even lower specific CO2 emissions. Decreasing the operating temperature in a SOFC allows the use of less complex materials and construction methods, consequently reducing plant and the electricity costs. A lower working temperature makes it also suitable for topping an existing steam cycle, instead of gas turbines. This is also the target of this study, repowering of an existing power plant with SOFC as well as gas turbines. Different repowering strategies are studied here, repowering with one gas turbine with and without supplementary firing, repowering with two gas turbines with and without supplementary firing and finally repowering using SOFC. Plant performances and CO2 emissions are compared for the suggested repowered plants

Transition Support Mechanisms for Communities Facing Full or Partial Coal Power Plant Retirement in New York

New York State is undergoing a rapid and unprecedented energy transformation, particularly in the electricity sector. As new resources and technologies emerge to meet the demands of 21st century life, regulators must balance the need for cost effective and equitable participation in wholesale power markets while maintaining reliability on the grid. Furthermore, it is critical that all New Yorkers participate fully in the promise of a revitalized and equitable energy future. Such a transformation requires that the needs of all communities are factored into the polices and regulations that move New York toward the bold goals set forth under its Reforming the Energy Vision (REV) initiative. The precipitous drop in natural gas prices, the decreased costs of wind and solar energy, and the rise in the cost of coal, have contributed to the mothballing or retiring of coal-fired and nuclear energy generators across the country, including in New York. Communities that have been home to the electric generation units of the past, particularly struggling coal-fired power plants, are especially vulnerable during this transformation, because these communities often rely on the generators for tax revenues, such as through Payments in Lieu of Tax agreements. New York has the opportunity to ensure a just transition for these communities by adopting new, clean energy resources, technologies, and markets while fostering a trained and skilled workforce to support its ambitious goals. For all New Yorkers to enjoy the new energy future, leadership must address the impact of lost jobs, declining economic activity and lost tax revenue, and must support essential services in impacted communities with the same level of urgency and expansive vision needed to balance the integration of new technologies in the most cost effective manner to maintain grid reliability. At the same time, state and federal funding must be allocated to communities in transition for the remediation and redevelopment of shuttered power plant sites, and to provide the necessary support, training and tools for impacted communities to actively participate in the transition and implementation of clean energy resources. The first section of this report examines the lessons learned from other jurisdictions in when and how to address the fiscal challenges of retiring electric generation units (EGU’s). The challenges New York faces are not unlike the challenges faced by communities, legislators, and plant owners during periods of deindustrialization of the late 1960’s through 1980’s, described in Section One below, which additionally provides: 1. An evaluation of case studies that address the process of retirement, decommissioning, remediation and preparation for redevelopment for future use, along with the state and federal policies and funding sources that made revitalization possible. 2. An overview of case studies that illustrate local government fiscal and workforce support to communities during periods of plant transformation. These periods encompass three historical phases: a. Deindustrialization of the 1960’s to1980’s; b. Federally Mandated Social Programs to Support Enforcement of Federal Regulations 1990’s to 2000; and c. Coal Plant Closures and Community Transition in the Age of Carbon Emissions Reductions: Federal and State Initiatives between 2000 to 2015; and Section Two examines four New York coal-fired generators, some of which are currently mothballed, retired, or struggling financially. In addition to providing profiles of each generator, Section Two also describes the Payment in Lieu of Taxes (PILOT) agreements that these generators have entered into with the towns, school boards, and counties in whose jurisdictions they are located. Due to the plants’ finances, several of the generators have made reduced PILOT payments in recent years, creating “budget gaps” for some of the communities. Finally, Section Three describes state and federal funding and support mechanisms that may be available to the New York communities described in Section Two. Because each community faces unique challenges and opportunities, this report does not attempt to provide specific recommendations for any of the communities. Rather, Section Three lists a number of support mechanisms that each community could consider in developing its own transition plan. New York State leadership can capitalize on the legislative legacy of prior eras and develop comprehensive approaches to reinvest in communities with obsolete industrial facilities that were once the primary source of jobs and economic activity, and revenue to local budgets

German wind power sector in crisis Energiewende under further threat. OSW COMMENTARY NUMBER 309 | 25.09.2019

The slowdown in expansion of onshore wind farms poses a serious threat to the German Energiewende. In 2018, wind power accounted for half of the electricity obtained from RES, and is considered the driving force behind the Energiewende. In the first half of 2019, only 81 new turbines of a combined capacity of 271 MW were connected to the grid in Germany, compared to an average annual increase in installed capacity of approximately 4500 MW from 2015 to 2017. There are problems with the system of auctions for new capacities, with the sector complaining among other things of protracted construction permit procedures, court action being taken by environmental organisations and residents, objections being raised by the Bundeswehr and Aviation Safety Agency, and laws restricting the area that can be used for construction. The crisis is having severe repercussions for companies in the German wind power sector. Some have gone bankrupt, with the workforce decreasing by approximately one fifth. The crisis in the wind power sector began at a time when climate issues were coming under greater public scrutiny, rendering the crisis a political liability due to doubt about whether the German 2030 climate policy target could be achieved. The impasse in growth of wind power could also derail plans to decommission the last nuclear power stations over the coming decade, and especially implementation of the roadmap for the gradual departure from coal

Sustainable land use against the background of a growing wind power industry

Among the measures discussed as remedies for CO2 emissions reduction renewable energies are prominent as they already provide marketable alternatives to fossil fuels. This holds true especially for wind power, which has multiplied more than twelve-fold on the global scale from 4,800 MW to over 59,000 MW between 1995 and 2005. This is the highest growth rate compared to all other sources of renewable energy. However, is this impressive expansion expected to continue in the near future? Although wind power as a clean technology helps to combat global warming and, as a renewable energy reduces the dependency on the supply of exhaustible fossil fuels, it is not without flaws. There are concerns over adverse effects on human beings, on wildlife and on the landscape. This paper discusses the limits for wind power generation and highlights important conflict areas that may roadblock further expansion of wind power and thus its potential to combat global warming. --