Tuesday, 1 November 2011

Accidentally speaking

The Caithness Windfarm Information Forum (CWIF - caithnesswindfarms.co.uk) has probably the only source of turbine related accident data available to the general public. The statistics are available here. There is a feeling at CWIF that the data displayed represents only the tip of the iceberg in terms of wind turbine related accidents and I agree with that sentiment. A fair percentage of the accidents documented in CWIF's listings are construction related. Given the difficult conditions often found on and and around wind farm construction sites, industrial accidents of this nature are difficult to prevent in their entirety.

The main areas of concern for turbine related accidents once a wind farm is operational are blade failure, fire, and tower faliure. Should we be concerned about this? I believe so. First of all, let's put the blade sizes into some sort of perspective. The blades in the following two images are approximately 131 feet (40 metres) in length (relative minnows in the industry):

© Copyright Paul Anderson and licensed for reuse under this Creative Commons Licence.

OK, so they're big - so what? Well, perhaps I can focus the mind a little with regard to blade failure:

The following image is particularly concerning as it shows damage to the blade tip area - which is the part of the blade that moves with the highest rotational velocity:

and a blade completely detached from a turbine:

Some more images of catastrophic turbine blade failure can be found here. Note the debris spread from this particular incident. How about incidents closer to home? Well, a blade from a turbine at Whitelee was recently shed causing the entire wind farm to be shut down for checks. A tiny mechanical or manufacturing defect, damage caused during transport and lightning or bird strike can all be listed as the ultimate cause of blade failure.

How about tower failures - yes, they happen - not often, but when they do, there is usually quite a mess:

Immagine the carnage that could be created if a tower collapse occurred whilst the blades were actually turning. Fires? Once agin - they happen. And the real problem with fires is that they can't really be effectively fought with the sort of equipment usually to hand. As a result, they are usually jut left to burn out:

I am not trying to be sensationalist here. I could have gone on for hours publishing pictures of similar failures but there seems little point really. CWIF claim 220 blade failures in their statistics, and 118 structural failures (up to September 2011). These then, are not the 'isolated and unique' occurrences often claimed by the industry. However, until the industry is more open with the general public we will have to rely upon the diligence of groups like CWIF to give us an idea of what is going on.

There are a number of points being made in this post. Operational wind turbine related accidents happen more frequently than a lot of people realise - and the absolute number of accidents can only be expected to increase as the number of operational wind farms increases. The actual reporting of accidents seems to be cloaked in secrecy; operators seldom seem prepared to admit to a problem. To my way of thinking, every turbine related incident should be reportable - and that information should be made publicly available. The last point is that to the general public, an operational wind farm is a no go area - would you want to walking close by one of the turbines pictured above when it was falling apart? For South Carrick and its immediate surrounds, such no go areas may extend to as much as 51,000 acres of previously, freely accessible land (that's an area nearly 20% larger than the city of Glasgow). So much for the right to enjoy the countryside - suddenly, the 'right to roam' doesn't seem very important to the politicians anymore. Technically, all that countryside is still open as before - but would you really want to go near these structures when they are operating?

Let's face it, wind farms are industrial facilities and it is about time they were teated as such. The industry needs to come clean and be open and honest so that people truly understand the physical risks associated with wind turbines; they are not benign, Earth saving structures; they are complex pieces of machinery that can and do fail in a number of rather alarming ways.