coffeeguyzz wrote:NWMossback clearly knows his stuff, but why listen to his experienced input if'n it is info one doesn't wish to hear?
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coffeeguyzz wrote:For those of us in the real world, the article "London Array turns two" describes actual operations of the world's largest offshore wind farm.
For comparison purposes, the Lackawanna Energy plant has 1.500 MW capacity, SIX TIMES the functional capacity (630*.4) of the London Array, is fueled by cheap nearby Marcellus gas, can be turned off an on in minutes, and has a staff of 30.
The offshore farm cranks out most prodigiously at night, requires 90 fulltime staff - most working 12 hour shifts - 6 crew boats, is subject to weather conditions, costs TWICE as much to build as Lackawanna, and has 50% rate of maintenance 'unscheduled', aka breakdowns.
NEVER happen in USA
What often happens is that the wind farm is upgraded with new turbines as the old turbines age or new technology makes new turbines cost effective for a replacement. This is called repowering and comes in 2 flavors: full repowering and partial repowering. Full repowering is where they take down most of the wind farm: turbines, towers, foundations, but leave the roads, buildings, and transmission lines. Partial repowering is where they leave the foundation and tower intact and simply replace the turbine parts. As for the old equipment, it is sometimes resold in second-hand wind turbine markets such as in Latin America, Eastern Europe, etc where it gets a second lease on life. Otherwise the equipment gets recycled.Newfie wrote:I wAs thinking more along the lines of the blades, towers and those zMASSIVE FOUNDATIONS. Or is it just assumed they will be abandoned in place.
Wind Power Project Repowering: Financial Feasibility, Decision Drivers, and Supply Chain EffectsRepowering as defined here includes two types of actions. Full repowering refers to the complete dismantling and replacement of turbine equipment at an existing project site. Partial repowering is defined as installing a new drivetrain and rotor on an existing tower and foundation. Partial repowering allows existing wind power projects to be updated with equipment that increases energy production, reduces machine loads, increases grid service capabilities, and improves project reliability at lower cost and with reduced permitting barriers relative to full repowering and greenfield projects. There is also the potential to offset repowering costs by recycling or selling the older equipment.
GE Adds Value to the US Wind Turbine Industry With its Repower OfferingGE Renewable Energy today announced at the AWEA Windpower Conference that it has repowered 300 wind turbines, the equivalent of adding 75 wind turbines worth of output. The National Renewable Energy Laboratory has estimated that the U.S. repowering market could grow to $25 billion by 2030. With the largest installed base in the US, GE is uniquely positioned to serve this growing market segment.
As the US wind industry matures, legacy units are old enough to benefit from this lifecycle extension program, which brings new value to wind farm customers through upgrades and technology advancements.
Anne McEntee, GE Renewable Energy Vice President and Services CEO said “The Repower program can include increasing a turbine’s rotor size, and upgrades to the gearbox, hub, main shaft, and main bearing assembly. This is an exciting opportunity to bring new life to older turbines and help them provide even more energy for years to come. Repowering is so much more than simply providing new wind turbine equipment—we’re bringing the entirety of GE to the table for our customers, providing options for servicing, grid solutions, forecasting and tailored financing solutions.” “The GE repower package provides the opportunity to modernize our windfarms, improving the efficiency and increasing the farm output. Repowering ensures our wind turbines not just remain productive, but perform better than ever.”
Was it one of these papers:Newfie wrote:Been digging around a bit, I’ve got some decent internet for a couple of days for a change
As to the Spanish report: I can’t find the dang thing. The gist is it was written by its two project managers, took a comprehensive look at all the installation and maintenance costs, and laid a format for the Total Life Cycle Analysis. If anyone can find it, I originally came across it here on PO, I would appreciate a link. Or just some search suggestions.
Comparative life cycle assessment of 2.0 MW wind turbinesAbstract: Wind turbines produce energy with virtually no emissions, however, there are environmental impacts associated with their manufacture, installation, and end of life. The work presented examines life cycle environmental impacts of two 2.0 MW wind turbines. Manufacturing, transport, installation, maintenance, and end of life have been considered for both models and are compared using the ReCiPe 2008 impact assessment method. In addition, energy payback analysis was conducted based on the cumulative energy demand and the energy produced by the wind turbines over 20 years. Life cycle assessment revealed that environmental impacts are concentrated in the manufacturing stage, which accounts for 78% of impacts. The energy payback period for the two turbine models are found to be 5.2 and 6.4 months, respectively.
Conclusions
This LCA study compared the environmental impacts of two 2.0 MW wind turbines using two methods (ReCiPe 2008 and energy payback). The tower, rotor, and nacelle are found to have the greatest contribution to the environmental impact in each case. For the tower, the large amount of steel required is the major contributor to cradle-to-grave environmental impact. One of the outcomes from this LCA study is the confirmation that the main life cycle environmental impacts of a wind turbine originate from the manufacturing stage. When compared to prior work, the results lead to a similar conclusion that environmental impacts are driven by the material consumption, especially steel.
It was shown that the use stage has an almost negligible environmental impact due to maintenance activities. In addition, the transportation distances of wind turbine components to the wind park site influenced environmental impact. The travel distance of model 1 is longer than model 2 by 16,000 km (approximately 50%), and some components for model 1 are transported from other continents. It was found that recycling is important to the environmental profile of the turbine, while transportation type can have a profound effect on life cycle impacts when components must travel relatively longer distances.
coffeeguyzz wrote:Ghung
That is a timely question for several reasons.
The biggest reason is the need for adequate natgas supply, and - consequently - the ferocious opposition to pipeline build out by renewable advocates.
However, the build out IS proceeding with many delays.
Two large pipelines are targeting the US southeast - Atlantic Coast Pipeline and Mountain Valley.
Once these are built (expected within 24 months), there will be future expansion potential which is much easier to accomplish.
There are already several CCGT plants being built or planned in the south east, and 26 in Ohio and Pennsylvania alone.
It's kind of a shame that anti fossil fuel folks have so thoroughly demonized natgas as the systems work most effectively with intermittent (think wind) supply.
VTS, trawling fishing boats are not compatible with remnant, sea-bottom structures.
This aspect is a very strong influence against offshore turbines in the northeast US.
GHung wrote:coffeeguyzz wrote:Ghung
That is a timely question for several reasons.
The biggest reason is the need for adequate natgas supply, and - consequently - the ferocious opposition to pipeline build out by renewable advocates.
However, the build out IS proceeding with many delays.
Two large pipelines are targeting the US southeast - Atlantic Coast Pipeline and Mountain Valley.
Once these are built (expected within 24 months), there will be future expansion potential which is much easier to accomplish.
There are already several CCGT plants being built or planned in the south east, and 26 in Ohio and Pennsylvania alone.
It's kind of a shame that anti fossil fuel folks have so thoroughly demonized natgas as the systems work most effectively with intermittent (think wind) supply.
VTS, trawling fishing boats are not compatible with remnant, sea-bottom structures.
This aspect is a very strong influence against offshore turbines in the northeast US.
Which is why sport fishing around these structures is generally good.
ROCKMAN wrote:Doesn't sound like there's an issue with either voltage or any other compatibility requirement.
kublikhan wrote:There has been some debate about whether wind turbines have a more limited shelf-life than other energy technologies. A previous study used a statistical model to estimate that electricity output from wind turbines declines by a third after only ten years of operation.
In a new study, researchers from Imperial College Business School carried out a comprehensive nationwide analysis of the UK fleet of wind turbines. They showed that the turbines will last their full life of about 25 years before they need to be upgraded. The team found that the UK’s earliest turbines, built in the 1990s, are still producing three-quarters of their original output after 19 years of operation, nearly twice the amount previously claimed, and will operate effectively up to 25 years. This is comparable to the performance of gas turbines used in power stations.
The study also found that more recent turbines are performing even better than the earliest models, suggesting they could have a longer lifespan. The team says this makes a strong business case for further investment in the wind farm industry.
New research blows away claims that ageing wind farms are a bad investment
That's the same paper I was talking about. My link was a high level overview of the paper, your link is the paper itself.NWMossBack wrote:Your link did not include the data - but here is a pretty good analysis that comes to a similar conclusion.
The wind farms are not mothballed at 15-20 years though. They are repowered(upgraded) to newer parts.NWMossBack wrote:Also, output degradation is obviously not the only consideration for the _economically useful_ lifespan. O&M costs increase over time, and with output simultaneously degrading it should be no surprise that the point when a turbine has reached it's maximum economic life is less than the original design estimate of 20 years, and a 15 year estimate seems to be reasonable.
The idea that wind farms only have 20-year useful lives “is ridiculous.” Warren Buffett’s MidAmerican Energy Co. said last month that it would upgrade hundreds of older turbines at power plants in Iowa. The reasons aren’t limited to age and health. Newer turbines produce more electricity than older models, so owners can downsize their power plants without reducing electricity output. And these jobs are sometimes easier than building new wind farms because power lines and permits are usually already in place.
kublikhan wrote:EROEI of wind is not 5:1. Depending on what source you use it's anywhere from 18:1 to 40:1:
My link was bad. here is the correct one:NWMossBack wrote:Your link purporting to show 40:1 does not discuss EROEI at all, and your other sources appear to be using "unbuffered" EROEI for wind. The EROEI after taking intermittency into account is around 5:1.
http://euanmearns.com/eroei-for-beginners/
Wind energy, backup power, and emissionsOverview of power grid operations
System operators always maintain significant “operating reserves,” typically equal to 5-7% or more of total generation. These reserves are used to deal with the rapid and unpredictable changes in electricity demand that occur as people turn appliances on and off, as well as the very large changes in electricity supply that can occur in a fraction of a second if a large power plant suffers an unexpected outage. Instead of backing up each power plant with a second power plant in case the first plant suddenly fails, grid operators pool reserves for the whole system to allow them to respond to a variety of potential unexpected events.
System operators use two main types of generation reserves: “spinning reserves,” (regulation reserves plus contingency spinning reserves) which can be activated quickly to respond to abrupt changes in electricity supply and demand, and “non-spinning reserves,” (including supplemental reserves) which are used to respond to slower changes.
Spinning reserves are typically operating power plants that are held below their maximum output level so that they can rapidly increase or decrease their output as needed. Hydroelectric plants are typically the first choice of system operators for spinning reserves, because their output can be changed rapidly without any fuel use. When hydroelectric plants are not available, natural gas plants can also be used to provide spinning reserves because they can quickly increase and decrease their generation with only a slight loss of efficiency. Studies show that using natural gas plants or even coal plants as spinning reserves increases emissions and fuel use by only 0.5% to 1.5% above what it would be if the plants were generating power normally.
Non-spinning reserves are inactive power plants that can start up within a short period of time (typically 10-30 minutes) if needed. Hydroelectric plants are frequently the top choice for this type of reserve as well because of their speedy response capabilities, followed by natural gas plants. The vast majority of the time non-spinning reserves that are made available are not actually used, as they only operate if there is a large and unexpected change in electricity supply or demand. As a result, the emissions and fuel use of non-spinning reserves are very low, given that they only rarely run, the fact that hydroelectric plants (which have zero emissions and fuel use) often serve as non-spinning reserves, and the very modest efficiency penalty that applies when reserve natural gas plants actually operate.
Accommodating Wind Energy
Fortunately, the same tools that utility system operators use every day to deal with variations in electricity supply and demand can readily be used to accommodate the variability of wind energy. In contrast to the rapid power fluctuations that occur when a large power plant suddenly experiences an outage or when millions of people turn on their air conditioners on a hot day, changes in the total energy output from wind turbines spread over a reasonably large area tend to occur very slowly.
While occasionally the wind may suddenly slow down at one location and cause the output from a single turbine to decrease, regions with high penetrations of wind energy tend to have hundreds or even thousands of turbines spread over hundreds of miles. As a result, it typically takes many minutes or even hours for the total wind energy output of a region to change significantly. This makes it relatively easy for utility system operators to accommodate these changes without relying on reserves. This task can be made even easier with the use of wind energy forecasting, which allows system operators to predict changes in wind output hours or even days in advance with a high degree of accuracy.
Moreover, changes in aggregate wind generation often cancel out opposite changes in electricity demand, so the increase in total variability caused by adding wind to the system is often very low. As a result, it is usually possible to add a significant amount of wind energy without causing a significant increase in the use of reserves, and even when large amounts of wind are added, the increase in the use of reserves is typically very small.
The conclusion that large amounts of wind energy can be added to the grid with only minimal increases in the use of reserves is supported by the experience of grid operators in European countries with large amounts of wind energy, as well as the results of a number of wind integration studies in the U.S. The table below summarizes the results of some of these studies.
On average, adding 3 MW of wind energy to the U.S. electric grid would reduce the emissions from fossil power plants by 1,200 pounds of CO2 per hour. Adding this amount of wind would at most require anywhere from 0 to 0.01 MW of additional spinning reserves, and 0 to 0.07 MW of non-spinning reserves.
kublikhan wrote:They calculated input energy and output energy making it easy to calculate EROEI. The energy input was calculated as being repaid in about 6 months(0.5 years) and assuming 20 years of output. 20 / .5 = 40. So 40:1 EROEI.
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