Illinois, Michigan, Minnesota, New York and Pennsylvania .
have signed on to the wind fast track
~~~
This effort may not be a breeze
The Great lakes are unique
Recently in the field of wind energy there have been reports of issues with cold temperatures.
Extreme weather conditions can compromise the structural integrity of wind turbines.
This was brought to light not long ago with a recent report of a Wind turbine in Cheyenne Wyoming, the turbine was subject to extreme cold temperatures and crumpled like a leaf, apparently when the temperatures get too cold, a lot of flexibility within a turbine is lost and it becomes brittle.
During the winter, “Lake Erie is subject to partial or sometimes complete ice cover due to its shallowness,” notes researcher James S. Dingman. “During a normal year, about 95% of the lake becomes ice covered with maximum ice cover occurring in late February.” The ice cover on Lake Erie is frequently broken up and blown about during the winter, and serious ice problems occur in the Eastern Basin [toward Buffalo and Western New York] due to the prevailing southwest wind.”
~~~~~~~~~~~~~~~~~
Daily Lake and River Ice Cover Averages:
Plots of Lake Ontario Ice Cover link -->here<-- Offshore wind development in the Great Lakes. After learning about New York’s quest for wind developers, for Great Lakes Offshore Wind projects, my first thought was would a normal offshore wind turbine withstand the ice conditions of the Great Lakes? I called a close friend with over 30 years experience measuring the pressures and uplift of ice in Lake Huron. He told me that the turbines will be subject to severe damage caused by ice pressures depending upon thickness. If the ice gets 24” thick, which it can, the horizontal pressure can be a minimum 35,000 lbs per foot of width. He told me that they have actually measured forces up to 60,000 lbs per foot based on Kerr- Nevel biharmonic differential equation describing a homogenous thin elastic plate on a nelastic foundation. This can be verified by Leonard Zabilansky at CRREL in Hanover, New Hampshire (Cold Regions Research Engineering Laboratory). This is only a brief covering of the complexity of Ice and Ice forces. Shortly after this conversation I found this report (New York’s offshore wind energy development potential in the Great Lakes Feasibility Study) prepared by AWS Truewind LLC in behalf of the NYSERDA I have pulled excerpts from the report and added a few comments of my own to view the complete 173 page report link--> here<--. Although technically feasible offshore wind development would be a costly undertaking not only from a construction standpoint but the issue of maintenance due to icing and foul weather conditions would be a major problem. The feasibility study suggests possibly the use of Coast Guard ice breakers to ferry people out to turbines for this, or helicopters. The United States Coast Guard is a federal agency, a branch of the military under the department of Homeland Security, with a clearly defined mission and is not a hired utility service at the beck and call of private enterprise for ferrying maintenance workers to and from turbine sites. Helicopters may not even be an option under foul weather conditions. Severe weather conditions including rough seas and pressure from ice would require the development of specialized techniques and infrastructure to make such a project feasible. Whether a project would be financially feasible is another issue. The feasibility study points out that special vessels exist worldwide for wind project installation; their availability in the Great lakes may be limited by jurisdictional concerns (i.e. the Jones act) as well as by passage way size through the St Lawrence Seaway and the Welland Canal. The Feasibility study is suggesting the possibly of the construction of one or more vessels specifically suited for offshore wind instillation on the Great Lakes. This is a never ending money pit. Technical problems: fresh water ice is harder than salt water ice so the turbine structures that are currently in use today for offshore applications even in cold climates are unsuitable for Great Lakes use. A complete new structural design would be required to withstand the ice load. Early experiences in Europe have shown that the turbines may be accessed by boat 80% of the time. This is due to variable weather conditions and sea states. As a result, turbine maintenance needs may take longer to address. The installed cost of an offshore wind plant can be twice as expensive as an equivalent onshore plant. Factors affecting offshore costs include the project’s water depth, distance from shore, geologic conditions, and the complexity of the installation procedure, which varies from site to site. Balance –of- plant costs (foundations, electrical systems, etc) are much more expensive offshore than onshore and acquiring financing is typically more difficult to obtain due to the higher perceived investment risk and limited experience in the U.S. Fresh water wind turbine access is more likely to be limited by lake ice conditions than rough sea states, with possible site access by boat reaching as low as 65% of the calendar year. Offshore wind turbine availability may be lower than onshore projects due to limited maintenance experience in the U.S. for offshore turbines and the harsh offshore operating environment, but little operational data is publicly available to quantify the significance of this parameter Another issue that is a problem for Great lakes off shore wind development how quickly the lakes freeze and the thickness of the ice. Temperatures below freezing can lead to ice accumulation on turbine blades and other components during inclement weather, which can temporarily reduce turbine output. Extremely low temperatures can cause a turbine to shut down to protect system components, resulting in loss of production. Ice combined with the severe weather conditions present structural issues never before addressed by the wind industry. Due to the lack of experience in freshwater offshore wind development the actual impact from ice is unknown. This whole endeavor could be nothing more than a monumental folly at taxpayers’ expense. This feasibility study points out that offshore wind costs twice as much as traditional wind. However, this is not even a traditional offshore wind project in that offshore wind development has never been undertaken in the Great Lakes. The Great Lakes area has its own unique marine weather environment. Managing the problems presented by the differences in fresh water ice structure alone will add additional costs to these projects. Coupled with the issues of dealing with the lack of special vessels for wind project installation these added expenses are seemingly endless and these costs will be passed on to the consumer either in the form of tax subsidies or in higher electricity rates.
Link -->here<-- to read US ARMY CORPS of ENGINEERS ~ Engineering and Design ~ Ice Engineering
FAA ~ RESTRICTIONS
Daily Lake and River Ice Cover Averages:
Plots of Lake Ontario Ice Cover link -->here<-- Offshore wind development in the Great Lakes. After learning about New York’s quest for wind developers, for Great Lakes Offshore Wind projects, my first thought was would a normal offshore wind turbine withstand the ice conditions of the Great Lakes? I called a close friend with over 30 years experience measuring the pressures and uplift of ice in Lake Huron. He told me that the turbines will be subject to severe damage caused by ice pressures depending upon thickness. If the ice gets 24” thick, which it can, the horizontal pressure can be a minimum 35,000 lbs per foot of width. He told me that they have actually measured forces up to 60,000 lbs per foot based on Kerr- Nevel biharmonic differential equation describing a homogenous thin elastic plate on a nelastic foundation. This can be verified by Leonard Zabilansky at CRREL in Hanover, New Hampshire (Cold Regions Research Engineering Laboratory). This is only a brief covering of the complexity of Ice and Ice forces. Shortly after this conversation I found this report (New York’s offshore wind energy development potential in the Great Lakes Feasibility Study) prepared by AWS Truewind LLC in behalf of the NYSERDA I have pulled excerpts from the report and added a few comments of my own to view the complete 173 page report link--> here<--. Although technically feasible offshore wind development would be a costly undertaking not only from a construction standpoint but the issue of maintenance due to icing and foul weather conditions would be a major problem. The feasibility study suggests possibly the use of Coast Guard ice breakers to ferry people out to turbines for this, or helicopters. The United States Coast Guard is a federal agency, a branch of the military under the department of Homeland Security, with a clearly defined mission and is not a hired utility service at the beck and call of private enterprise for ferrying maintenance workers to and from turbine sites. Helicopters may not even be an option under foul weather conditions. Severe weather conditions including rough seas and pressure from ice would require the development of specialized techniques and infrastructure to make such a project feasible. Whether a project would be financially feasible is another issue. The feasibility study points out that special vessels exist worldwide for wind project installation; their availability in the Great lakes may be limited by jurisdictional concerns (i.e. the Jones act) as well as by passage way size through the St Lawrence Seaway and the Welland Canal. The Feasibility study is suggesting the possibly of the construction of one or more vessels specifically suited for offshore wind instillation on the Great Lakes. This is a never ending money pit. Technical problems: fresh water ice is harder than salt water ice so the turbine structures that are currently in use today for offshore applications even in cold climates are unsuitable for Great Lakes use. A complete new structural design would be required to withstand the ice load. Early experiences in Europe have shown that the turbines may be accessed by boat 80% of the time. This is due to variable weather conditions and sea states. As a result, turbine maintenance needs may take longer to address. The installed cost of an offshore wind plant can be twice as expensive as an equivalent onshore plant. Factors affecting offshore costs include the project’s water depth, distance from shore, geologic conditions, and the complexity of the installation procedure, which varies from site to site. Balance –of- plant costs (foundations, electrical systems, etc) are much more expensive offshore than onshore and acquiring financing is typically more difficult to obtain due to the higher perceived investment risk and limited experience in the U.S. Fresh water wind turbine access is more likely to be limited by lake ice conditions than rough sea states, with possible site access by boat reaching as low as 65% of the calendar year. Offshore wind turbine availability may be lower than onshore projects due to limited maintenance experience in the U.S. for offshore turbines and the harsh offshore operating environment, but little operational data is publicly available to quantify the significance of this parameter Another issue that is a problem for Great lakes off shore wind development how quickly the lakes freeze and the thickness of the ice. Temperatures below freezing can lead to ice accumulation on turbine blades and other components during inclement weather, which can temporarily reduce turbine output. Extremely low temperatures can cause a turbine to shut down to protect system components, resulting in loss of production. Ice combined with the severe weather conditions present structural issues never before addressed by the wind industry. Due to the lack of experience in freshwater offshore wind development the actual impact from ice is unknown. This whole endeavor could be nothing more than a monumental folly at taxpayers’ expense. This feasibility study points out that offshore wind costs twice as much as traditional wind. However, this is not even a traditional offshore wind project in that offshore wind development has never been undertaken in the Great Lakes. The Great Lakes area has its own unique marine weather environment. Managing the problems presented by the differences in fresh water ice structure alone will add additional costs to these projects. Coupled with the issues of dealing with the lack of special vessels for wind project installation these added expenses are seemingly endless and these costs will be passed on to the consumer either in the form of tax subsidies or in higher electricity rates.
Link -->here<-- to read US ARMY CORPS of ENGINEERS ~ Engineering and Design ~ Ice Engineering
FAA ~ RESTRICTIONS
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