The following is a series of questions from community members and the general public with answers provided by the University of Maine and the Maine Aqua Ventus (MAV) team.
Question (Q): What is the estimated life of platforms?
Answer (A): 60-75 years – The full life depends on accounting methods for depreciation and amortization.
Q: What is the estimated life of the subsea transmission cable?
A: 20+ years, depending on the manufacturer’s warranty and actual wear.
Q: What is the estimated life of the wind turbines?
A. 20 or 25 years, depending on the manufacturer.
Q: What is the expected maintenance period for the platforms?
A: Scheduled 2 trips per year @ 4 days, unscheduled 4 trips per year @ 1 day.
Q: What is the expected maintenance schedule for the subsea transmission cable?
A: Annual Inspection @ 2 days (with ROV).
Q: What is the expected maintenance schedule for the moorings?
A: Annual Inspection @ 2 days (with ROV).
Q: What is the expected maintenance schedule for the turbines?
A: Scheduled 1 trip/year @ 5 days, unscheduled 4 trips per year @ 1 day per trip.
Too the extent possible, boat/vessel trips would be combined for the above.
Q: What will be the relationship between MAV and Central Maine Power (CMP)?
A: Under the power contract for the project, CMP will buy the power from MAV.
Q: If on the odd chance that Monhegan comes to love its wind turbines, is there the possibility that we could take them over at the end of twenty years instead of dismantling and become our own power generating company selling power to CMP?
A: That is an interesting question and one we had not considered. I think it is worthy of more consideration and conversation.
Q: Is it certain that if there is a power cable there will also be the fibre-optic cable?
A: Pretty certain – that is the cable spec that we are getting quotes on.
Q: Will the fibre-optics (FO) be state of the art and allow us to link with other entities at the maximum speed available at any time?
A: I am told that the FO will be multiple fiber stands and is considered “dark fiber”. Technically it will be able to provided the fastest speed available. Speed is related to the equipment you have on each end, and who connects it to the internet. That would be between the Island and an ISP (internet service provider) such as a GWI, OTT, or Fairpoint.
Q: What is the estimated cost of laying the cable and completing all the hookups?
A: I do not have a good enough quote on that, that I would feel comfortable sharing yet.
Q: How tough is the cable? Have they gotten better so that they are not so vulnerable to breaking at the land/water interface or from fishing and shipping accidents?
A: The cables are very robust and used throughout the world. They are engineered to withstand this environment and are laid with methods and locations to minimize wear and avoid being dragged. Considering the trans atlantic cable (communications) was laid in the mid 1850’s and the use of electrical submarine cables for power began in the 1950’s there is a lot of history and experience.
This site has a pretty good overview on submarine cables
http://www.openelectrical.org/wiki/index.php?title=Subsea_Power_Cable