Web exclusive, September 24, 2009
Peninsula Power group visits Vinalhaven wind farm
By special invitation, a group of five members of Peninsula Power visited Vinalhaven’s wind power project to see the construction phase of their three-tower farm, according to a press release. Traveling by private boat from Stonington across 10 miles of open water and picked up by a Cianbro van, the group was received by Vinalhaven’s wind project head, George Baker. Wearing hard hats and safety glasses, the group walked in the access road to see the ground preparation for the three towers.
Blasted ledge was crushed on-site to make some of the road, which is 30’ wide between the towers to accommodate the crane which must be used to lift the pieces of each tower. The road will be back-filled and vegetated, allowing for a 12’ access road, upon completion.
The group was impressed with the scale of the pole, nacelle, and blades for each of the three units being erected. The 150’ blades made of fiberglass and balsa wood are S-shaped, are as wide as a person is tall, and are flexible to the touch at the tip. The base section of each mono pole is 12’ around with a ladder welded to the inside. Each pole will be about 250’ tall upon completion and will offer a long climb for any maintenance personnel headed for the nacelle where the generator is. The nacelle is the 20’ by 12’ hub where the blades are mounted and the working parts of the machine are located. The concrete foundations are anchored to solid granite ledge with massive steel bolts drilled 40’ deep.
A special engineer is needed just for the grounding system to protect the equipment from lightning strikes. A web of grounding material radiates 200’ or so from the base in four directions to compensate for the very poor electrical conductivity of granite. All the parts are being shipped by barge from Rockland on flatbed trucks, an added expense that mainland projects will not have to bear. Blades shipped from Brazil arrive at Eastport where they are picked up by truck, delivered and off-loaded at the site.
The visit gave an idea of what Peninsula Power would be doing if they are successful in reaching the construction phase after answering the questions posed in their feasibility study.
Peninsula Power is based on the Blue Hill Peninsula and seeks to provide power at a cost at or below the current standard offer.