Once a wind turbine reaches the end of its operational life or becomes outdated, it must be decommissioned and removed from the site. As of the first quarter of 2023, data from the United States Geological Survey reveals the existence of 72,731 wind turbines spread across 43 states, encompassing territories such as Guam and Puerto Rico.

According to the latest introduced legislation, U.S. representatives from Colorado are proposing that wind energy companies should be required to remove decommissioned wind turbines from leased land before becoming eligible for federal tax credits.

Managing wind turbine waste: rise of regulations

As wind turbines reach the end of their operational lives, the disposal and recycling of wind turbine blades can become a complex issue. These blades, often made from composite materials like carbon fiber or glass, are challenging to recycle using conventional methods, leading to considerable waste.

Due to their large size and durable composition, finding sustainable solutions for handling used wind turbines is crucial. Landfill disposal has been a common approach, but this method presents a different set of environmental and lifecycle cost challenges. 

Wind turbines have an operational lifespan of several decades, so waste management during decommissioning is a long-term consideration. Waste regulation aims to address concerns related to the disposal, recycling, and environmental impact of wind turbine components at the end of their useful life. 

Because the wind energy industry is relatively young, U.S. wind farm operators and policymakers have yet to encounter decommissioning challenges. Several states are starting to develop specific waste regulations for wind turbines. 

One of them is Texas, which holds the top position among all states regarding the number of wind turbines and boasts the highest installed capacity, measured in megawatts. With the rapid growth of Texas wind farms, the issue of handling wind turbine waste, particularly the disposal and recycling of wind turbine blades, has become a significant concern. 

Texas has seen efforts to develop more sustainable wind turbine waste management solutions. Some initiatives focus on innovative recycling technologies, exploring ways to break down or repurpose the composite materials used in wind turbines. The Texas legislature defines decommissioning requirements on any person who leases property from a landowner to operate a wind farm. The state’s efforts reflect the recognition that addressing wind turbine waste is essential for the sustainability of the wind energy sector and minimizing the environmental footprint of renewable energy infrastructure as a whole.

As another example, wind turbine waste management in Oklahoma shares similarities with other states with a significant wind energy presence but has unique challenges and initiatives. Oklahoma defines steps related to the proper decommissioning of a wind energy facility and the requirement for energy companies to remove decommissioned wind turbines from leased land. Oklahoma is also actively exploring various strategies for more responsible wind turbine waste management.

Waste regulation for wind turbines is essential for the continued growth and sustainability of wind energy as a renewable energy source, as it helps mitigate potential negative impacts on the environment while maximizing the benefits of clean energy generation.

New legislation in Colorado

Colorado has been investing in wind energy projects, and its wind capacity has steadily increased over the years. Naturally, wind turbines are predominantly installed in regions with strong and consistent winds, such as the eastern plains and southern parts of the state. 

*Map shows the location of the operating wind farms in Colorado

According to the EIA’s latest available information, Colorado has an installed capacity of around 5,200 MW of wind energy. Their wind farms include nearly 2,800 wind turbines.

The graphs below show the growth in wind capacity within the state for the last 10 years.

Colorado’s Wind Energy for the last 10 years. Source:  FirmoGraphs Power Mart, including EIA data, created in Qlik Sense

Colorado lawmakers have introduced a new legislative proposal that mandates wind energy companies to be responsible for the removal of decommissioned wind turbines within the state.

The bill aims to modify the Internal Revenue Code, making it mandatory for energy companies to remove decommissioned wind turbines from leased land to be eligible for federal tax credits. Currently, there is no requirement for wind energy companies to take responsibility for removing decommissioned wind turbines from leased land. As a result, property owners, often farmers and ranchers, bear the burden of turbine removal. This shift in legislation underscores the growing importance of addressing the challenges associated with renewable energy infrastructure at the end of its useful life.

A new report by the National Renewable Energy Laboratory (NREL) examines the types of clean energy technologies, along with the scale and pace of deployment needed for the U.S. to reach 100% clean electricity by 2035.

The NREL study, Examining Supply-Side Options to Achieve 100% Clean Electricity by 2035, found multiple pathways to a decarbonized grid by 2035. However, the exact technology mix and costs would be determined by research and development, manufacturing, and infrastructure investment decisions made over the next decade.

NREL said the study scenarios considered many new factors: a 2035 full decarbonization timeframe, higher levels of electrification and an associated increase in electricity demand, increased electricity demand from carbon dioxide removal technologies and clean fuels production, higher reliance on existing commercial renewable energy generation technologies, and greater diversity of seasonal storage solutions. The report was also influenced by decades of prior research.

For each scenario, researchers modeled the least costly generation, energy storage, and transmission investment portfolio to maintain reliable power throughout the year.

“For the study, [NREL’s Regional Energy Deployment System] helped us explore how different factors—like siting constraints or evolving technology cost reductions—might influence the ability to accelerate renewable and clean energy technology deployment,” said Brian Sergi, a co-author of the study.

Clean technologies must scale up quickly

As modeled by NREL, wind and solar energy would provide 60%–80% of generation in the least-costly electricity mix in 2035. The overall generation capacity would grow to roughly three times the 2020 level by 2035—including a combined 2 TW (terawatts) of wind and solar.

To achieve those levels would require an additional 40–90 GW of solar on the grid per year and 70–150 GW of wind per year by the end of the decade, said NREL. That is more than four times the current annual deployment levels for each technology.

If challenges arise around siting and land use restrictions, researchers said nuclear power capacity would help make up the difference. However, nuclear resources would need to more than double the current installed capacity.

Across four scenarios modeled by NREL, 5–8 GW of new hydropower and 3–5 GW of new geothermal would also be deployed by 2035. Energy storage between 2–12 hours of capacity would also increase, with 120–350 GW of capacity deployed by 2035.

NREL also said seasonal storage capacity in 2035 could range from about 100 to 680 GW. Seasonal storage is important when clean electricity makes up about 80%–95% of generation and a mismatch exists between variable renewable supply and demand.

Seasonal storage is represented in the study as hydrogen-fueled combustion turbines, but it could also include other emerging technologies.

In all scenarios, significant transmission is also added in many locations, mostly to deliver energy from wind-rich regions to load centers in the eastern U.S. As modeled, the total transmission capacity in 2035 is one to almost three times the current capacity. That would require between 1,400 and 10,100 miles of new high-capacity lines per year, assuming new construction were to start in 2026.

Clean energy benefits

In all modeled scenarios, NREL found that the health and climate benefits associated with fewer emissions exceed the power system costs to get to 100% clean electricity.

To decarbonize the grid by 2035, researchers said the total system costs between 2023 and 2035 would range from $330 billion to $740 billion. The scenarios with the highest cost modeled by NREL included restrictions on new transmission and other infrastructure development.

In the scenario with the highest cost, the amount of wind to be delivered to large population centers would be constrained, with more storage and nuclear generation deployed.

Overall, researchers said that as a result of the emission reductions and better air quality, up to 130,000 premature deaths would be avoided in the coming decades, saving $390 billion to $400 billion. Those totals would likely exceed the cost of decarbonizing the electric grid.

NREL said that when factoring in the avoided cost of damage from the impacts of climate change, a net-zero grid could save more than an additional $1.2 trillion.

“The benefits of a zero-carbon grid outweigh the costs in each of the more than 100 scenarios modeled in this study, and accelerated cost declines for renewable and clean energy technologies could lead to even larger benefits,” said Patrick Brown, another co-author.

Headwinds to decarbonization

NREL identified four key challenges that must be addressed in the next decade, through further research and other societal efforts, to enable full power sector decarbonization.

Dramatic acceleration of electrification

Electrification of some end-use energy services in the buildings, transportation, and industrial sectors is a key strategy for decarbonizing those sectors. NREL said increased electrification also increases overall electricity demand and the scale of the power system that needs to be decarbonized.

New energy infrastructure

This would include siting and interconnecting new renewables and storage at a rate three to six times greater than recent levels, which would set the stage for doubling or tripling the capacity of transmission, upgrading the distribution system, building new pipelines and storage for hydrogen and CO2, and/or deploying nuclear and carbon management technologies. The recently-enacted Inflation Reduction Act could jumpstart the deployment needed by making it more cost-effective.

Expanded clean energy manufacturing

The unprecedented deployment rates would require growth in raw materials, manufacturing facilities, and a trained workforce throughout clean energy supply chains. NREL said further analysis is needed to understand how to rapidly scale up manufacturing.

Continued R&D

NREL said technologies currently being deployed widely can provide most of U.S. electricity by 2035 in a deeply decarbonized power sector, but achieving a net-zero electricity sector at the lowest cost will take advances in research & development into emerging technologies—particularly to overcome the last 10% to full decarbonization.

NREL said getting from a 90% clean grid to full decarbonization could be accelerated by developing large-scale, commercialized deployment solutions for clean hydrogen and other low-carbon fuels, advanced nuclear, price-responsive demand response, carbon capture and storage, direct air capture, and advanced grid controls.

What about the new law?

The new report follows the enactment of the Inflation Reduction Act (IRA), which is estimated to reduce economy-wide emissions in the U.S. to 40% below 2005 levels by 2030. Initial analysis from the U.S. Department of Energy (DOE) estimates that grid emissions could decline to 68%–78% below 2005 levels by 2030.

NREL said the longer-term implications of the new law are uncertain, but they likely will not get the U.S. all the way to 100% carbon-free electricity by 2035.

None of the scenarios presented in NREL’s report include energy provisions in the IRA or the previously enacted infrastructure law, but researchers said their inclusion is not expected to significantly alter the 100% systems explored—and the study’s insights on the implications of achieving net-zero power sector decarbonization by 2035 are expected to still apply.

NREL’s study was funded by DOE. For more, here is a closer look.