Work on Lowell wind farm to start in August

[Kevin Rooney]

From the Burlington Free Press. According to the article, 21 turbines will be erected. It seems to have local support as well.

 

[Craig]

... It seems to have local support as well.

Not surprising when the town has been promised between 410K and 530K annually.

The approval came contingent on satisfaction of 44 conditions having due with permits, pre-construction surveys, construction damage and dozens of other concerns. Among them: Filing a decommissioning plan with a detail estimate of costs necessary to mothball the wind project.

This will become very important 5-7 years after commissioning the project.

 

[Kevin Rooney]

This will become very important 5-7 years after commissioning the project.

Could you explain why you think this decommissioning plan is necessary earlier? After all, windfarms are in use all over the globe, aren't inherently hazardous (except possibly to birds) and typically have a useful life of many years.

 

[peakbagger]

The typical mean time between failure for large gearboxes is about 6 to 7 years in continuous use. Windmill gearboxes are "severe service" as they have to speed up rather than gear down which means they have high inertia components exposed to wind turbulence on the input shaft.The cost to replace the gearboxes are substantial and require a large crane to be moved back to the site which usually requires reclearing the access ways developed when the farm went in. An owner may look at the numbers and decide that when the gearboxes fail, that they write off the project and leave the windmill standing. This has happened before on smaller scale turbines in California at Altamont pass.

The main reason wind farms are currently economic is the power produced is heavilly subsidized. It can be argued that competing mature technologies also are heavilly subsidized, but the wind Production Tax Credit is a tempting political target which has been "on again off again". If it goes away, the value of the power produced by the wind turbine is minimal and again, an owner might elect to walk away leaving a dead turbine. I doubt that is the case in Vermont but who knows who will own the turbines in a few years as these project get sold frequently. In all cases having a independently funded decomissioning fund will assure that the dead turbines are removed to some extent. I expect the foundations will remain but at least the towers and blades will go away.

My prior employer and GE are designing or producing direct drive wind turbines that eliminate gearboxes which conceivably should increase the longevity and make long term maintenance easier but the majority sold and installed currently are geared. Clipper makes one with mutiple gearboxes that can be changed without a crane but it is a fairly complex unit. The Northern Power NW-100 direct drive (used at the Mountain View Grand) is about 20% more expensive than competing geared units so even with more longevity many financial models that are focused on the short term may make the extra cost uneconomical.

An interesting article about negative power rates shows that the current wind strategy isnt working real well

http://www.bloomberg.com/news/2010-04-22/windmill-boom-curbs-electric-power-prices.html

 

[Craig]

The main reason wind farms are currently economic is the power produced is heavilly subsidized.

I would also add that current state and federal mandates are a strong incentive to consider wind energy.

In all cases having a independently funded decomissioning fund will assure that the dead turbines are removed to some extent. I expect the foundations will remain but at least the towers and blades will go away.

I would take this one step further and suggest any decommissioning plan should restore the site to "it's original state".
This may drive more renewable design and construction criteria for these projects.

Additional Reading

 

[RoySwkr]

Could you explain why you think this decommissioning plan is necessary earlier? After all, windfarms are in use all over the globe, aren't inherently hazardous (except possibly to birds) and typically have a useful life of many years.

Some people particularly in VT think views of pristine ridges are desirable and should be preserved through regulation, etc. It's one thing to allow towers which actually produce electricity, but having junk towers with no power is the worst of both worlds. [cf. Pemi bridge removal]

At the Searsburg VT wind farm, when a blade failed they couldn't get an exact replacement hence had to buy 3 new ones to balance. One of the towers had a more expensive part fail and was taken completely out of service due to cost. Technology is advancing and they don't keep making old parts any more than you can buy a replacement 486 processor. If the price they get for power changes, the whole operation can become uneconomical.

I am probably one of the few folks here who has hiked in the Lowell Mtns, once where the towers will be and once across the town line to the S. Sure the woods are nice but I can see why nobody considers them special.