Repowering older wind turbines, which involves replacing aging turbines or components, is becoming more common in the United States as the turbine fleet ages and as wind turbine technology advances. Newer turbines tend to be larger and installed at greater heights, allowing for more capacity per turbine. About 12% of the wind turbines in the United States were installed before 2000, but these turbines make up only 2% of the installed wind electricity generating capacity.
Federal production tax credits provide an incentive to increase electricity generation from existing wind turbines. In December 2015, the production tax credit (PTC) was extended until the end of 2019. The four-year extension and legislated phase-out of the PTC is expected to encourage many asset owners to repower existing wind facilities to requalify them to receive another 10 years of tax credits. A facility may still qualify for the PTC as long as at least 80% of the property’s value is new. This provision allows many owners to repower existing turbines without completely replacing them.
Fully repowering wind turbines involves decommissioning and removing existing turbines and replacing them with newer turbines at the same project site. Full repowering has mostly occurred in California, where many turbines were installed at high-wind sites before 1990.
Partial repowering involves leaving some portion of the existing wind turbine and replacing select components. By partially repowering, owners can increase hub heights and rotor diameters to produce more energy.
Although wind turbines are designed with lifespans of between 20 and 25 years, wind capacity factors decline with age as mechanical parts degrade, according to the U.S. Department of Energy’s Wind Technologies Market Report. The United Kingdom’s Engineering and Physical Sciences Research Council in 2014 indicated that, on average, the output of wind turbines declines by 1.6% each year. Repowering can increase the output of a wind facility, improve reliability, and extend the life of a facility by taking advantage of advances in wind turbine technology.
Newer turbines tend to rotate much more slowly and quietly than older, smaller turbines, turning at 10 to 20 revolutions per minute (rpm) instead of 40 to 60 rpm. Slower wind turbine rotations alleviate issues such as bird mortality and shadow flicker.
Repowering generally requires significantly less investment compared with new projects. However, repowering wind turbines does present some challenges. For example, the risk of failure may increase when reusing components such as towers and foundations that were designed for smaller turbines. Other challenges may include renegotiating power purchase agreements, interconnection agreements, and leases.
According to General Electric (GE), the largest wind turbine installer in the United States, repowering wind turbines can increase the fleet output by 25% and can add 20 years to turbine life from the time of the repower. General Electric has repowered at least 300 wind turbines, and the company expects this market to grow. MidAmerican Energy recently awarded a contract to GE Renewable Energy to repower as many as 706 older turbines at several wind farms in Iowa. After repowering, each turbine is expected to generate between 19% and 28% more electricity.
The National Renewable Energy Laboratory (NREL) has indicated that annual U.S. wind repowering investment has the potential to grow to $25 billion by 2030. EIA data indicate that three projects are currently planned for repowering: Mendota Hills, LLC in Illinois and Sweetwater Wind 2 LLC in Texas are scheduled for repowering in 2018, and Windpark Unlimited 1 in California is scheduled for repowering in 2022.
In addition, Rocky Mountain Power has announced its intent to repower wind turbines in Wyoming and is currently awaiting a public hearing on the issue. NextEra Energy is planning to repower two wind farms in Texas by the end of this year.
More information about electric generators in the United States is available in EIA’s Annual Electric Generator Report. The early release of the 2016 version of this report was made available in August; the final version is scheduled for release in November.
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At a time when most of the news in the North Sea is about exits – ExxonMobil has just sold its unoperated upstream assets in Norway and ConocoPhillips has departed the UK section of the North Sea – there are still sparks of brightness in this long-mined offshore area. Equinor’s Johan Sverdrup field which contains some 2.7 billion barrels of oil equivalent has started up, two months ahead of schedule and US$4.3 billion below original cost estimates.
When it hits peak production, this new ‘North Sea giant’ will produce up to 660,000 b/d of crude oil, accounting for a third of all oil production in Norway. When complete, the Johan Sverdrup development will be one of the largest in the Norwegian Continental Shelf. It is a shot in the arm that Norway’s industry needs right now. Equinor has had a good track record in making new discoveries over the past two years, but they all mainly small and cannot outweigh declining production elsewhere. John Sverdrup is very different. Discovered in 2010, Johan Sverdrup straddles two separate production licences, discovered as Avaldsnes by Lundin Petroleum and Aldous Major South by Equinor and the field was renamed to its current form in 2012. Equinor holds a 42.6% stake in the field, with Lundin Norway, Petoro, Aker BP and Total constituting the rest.
The project has been championed as a model of the lower-cost, innovative thinking approach that the Norwegian upstream has taken since the 2014 downturn of the oil and gas industry. With first oil already flowing, it will help reverse the steady decline in Norwegian oil production, which fell to 1.65 million b/d in August, down 3.9% m-o-m and down from the all-time peak of 3.4 million b/d in 2011. Prudence paid off; green-lit in 2015, Equinor and its partners managed to secure significant discounts on services and equipment, resulting a break-even cost of less than US$20/b. The location of John Sverdrup is also crucial; believing the Norwegian Continental Shelf to be fully explored, activity has shifted to the Barents Sea. But though there are some big fields in the Barents coming onstream, exploration there has generally underperformed. So the field has been seen as a cause for hope, discovered in a mature basin 160km from Stavanger that was thought to be completely tapped out
Interestingly, John Sverdrup also has wider implications beyond the oil industry. With production set to reach 440,000 b/d by mid-2020, it will contribute about US$100 billion to the Norwegian state coffers over 50 years. It will inject additional fuel into the Norwegian Oil Fund – the country’s sovereign wealth fund – that recently decided to jettison upstream oil stocks (while keeping downstream oil stocks). This illustrates a dichotomy: while Norway as a whole is supportive of clean energy, oil & gas remains a crucial backbone of the country’s economy. So while the conversation around the North Sea will still centre around decommissioning and departures, Johan Sverdrup is proof that there are still (big) pockets of opportunity underneath these cold waters.
Canada is one of the world’s top energy producers and is a principal source of U.S. energy imports.
Petroleum and other liquids
Canada’s oil sands have significantly contributed to the recent and expected future growth in the world’s liquid fuel supply, and they comprise most of the country’s proved oil reserves, which rank third globally.Reserves
Canada is one of the world’s largest producers of dry natural gas and is the source of most U.S. natural gas imports.Reserves
As government policy attempts to lower domestic coal consumption, up to 50% of Canada’s coal production is exported.Reserves
Headline crude prices for the week beginning 30 September 2019 – Brent: US$59/b; WTI: US$54/b
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