Documents filed under Structural Failure
On December 24, 2015, a Vestas wind turbine collapsed in Lemnhult, Sweden. More than a year later, the Swedish Accident Investigation Authority has launched its report. The full report, in Swedish, can be accessed by clicking the links on this page. An English summary which is also provded in the report is posted below. Images of the collapsed Vestas V112 turbine can be found here.
This study examined how far full turbine blades, pieces of turbine blades and ice fragments could throw from an operating wind turbine. Full-blade pieces reached approximately 700, 900 and 2000 meter distances when tip speeds were 70, 100 and 150 m/s, respectively.
This paper examines the types of major failures found in utility-scale wind turbines and makes recommendations for periodic inspections. The first section of the paper is provided below. The full paper can be accessed from the links on this page.
This paper aims to summarize the current state of knowledge in this area by fire problems with wind turbines. The authors found that fire is the second leading cause of catastrophic accidents in wind turbines (after blade failure) and accounts for 10 to 30% of the reported turbine accidents of any year since 1980’s. In 90% of the cases, the fire leads to a total loss of the wind turbine, or at least a downtime that results in the accumulation of economic losses.The Abstract and Conclusions of the paper are provided below. The full paper can be accessed by clicking the link(s) on this page.
This important report examines the failures of wind turbine blades and the possible origins of the problems. The abstract and an excerpt of the report is provided below. The full report can be accessed by clicking the links on this page.
This paper investigates the influence of weather and location on wind turbine failure rate and downtime, to understand the root causes and consequences of failure. The weather data were analysed to find the wind turbine failures and weather conditions and then cross-correlate them.
Wind mills are the cheap and efficient generator of electricity. While the wind mills are patronized in India by the big corporate houses and medium scale industries for various reasons including the tax benefits offered by government these units are subject to fire, lightning and break down losses. This article highlights the possible break down failures of wind mills and suggests some key recommendations.
Following the catastrophic failure of two Vestas wind turbines on Feb 22 and 23, 2008, the Danish energy agency requested an investigation into the events. A report was produced by engineers at Risø DTU. Below is the report translated into English. The original report, in Danish, can be accessed by clicking on the link below. A video of one of the failures can be seen here: http://www.windaction.org/videos/14294 . It is important to note that the debris from the first turbine failure which occurred on February 22 spread as far as 700 meters (2200 feet) away. Risø DTU is formerly a government research institution under the Danish Ministry of Science, Technology and Innovation.
This brief document provides a case study of a wind energy facility in Texas and the effect of lightning strikes on wind turbine blades. Despite the 1.5 MW turbine blades having been equipped with lightning protection, the blades failed as a result of lightning strikes.
This short GE Energy document explains the risk in the event of extreme wind conditions including hurricane or tornado and any mitigation. Note, the document acknowledges the risk of blade throws and tower collapse.
This paper examines the damages of all six operating wind turbines on Miyakojima Island by Typhoon Maemi on September 11, 2003.
"Today, the task before the Joint Committee (regarding Bill S40) is to hear from the public on what would appear simple - the giving and taking of “driveway” easements between the Commonwealth’s Wachusett Reservation (Stagecoach Trail) and the Town of Princeton’s legal “right of way” for its wind power site. As well, the town is offering the to transfer to the Commonwealth, ownership of, five acres of their 16-acre wind site. I urge the Joint Committee for Bill S40 to carefully consider the following with regard to your recommendations an for easement exchange and accession of land from Princeton: 1. The Wachusett Wind Site is a 16 acre parcel wholly surrounded by the Wachusett Reservation and flanked within few feet, on three sides, by the well traveled Midstate, Harrington and Stagecoach trails. This portion of the state park is accessible and popular. 2. The present eight windmills are 120-feet high and are proposed to be replaced with two windmills as high as a 35- story building and with blades that stretch as wide as a football field - windmills whose elevation will come with 150- feet of the mountain’s elevation. 3. In the wintertime Wachusett experiences unusual ice storms in number and severity 4. In the wintertime, the windmills accumulate ice - then release it when it melts and falls, when it is blown off by wind or is thrown it off by the rotating blades 5. This ice has put holes in the roofs of utilty buildings on the wind farm and scattters itself across the fully accesssible wind site, the state reservation and hiking trails, threatening state park viisitors The risk associated with being struck windmill ice can be quantified and is relative to one’s distance from the windmills and will increase geometrically with the proposed windmills. 6. Windmills and wind data collection towers at Wachusett have structurally failed five times in twenty years on the Town of Princeton (PMLD) site. This also threatens the state park visitors as well with collapsing metal structures and flying blades. Proposed windmills and data towers will not be installed in compliance withthe manufacuturer’s recommendations and safety warnings."......
BBC Research & Consulting's 2005 report for the National Wind Coordinating Committee that studies 9 wind plant sitings in an effort to identify circumstances that distinguish welcomed projects from projects that were not accepted by communities.