Taking a Look at the Decommissioning of Wind Turbines and Solar Panels

When green energy goes belly-up: What happens to solar panels and turbines when they're decommissioned?

The swooshing of windmills to grind out electrons. Solar panels harvesting photons from the sun. Wind and solar installations are a source of pride for proponents of green energy. From small-scale renewable energy to massive utility-scale solar and wind farms, the cumulative solar and wind energy produced in the United States accounts for 13 percent of all energy produced (141 million kilowatts in 2019).

But these technological wonders that allow humans to harvest energy from the wind and sun don't just disappear when they break or expire. When they've reached the end of their serviceable life, the materials go somewhere. When turbines and panels have generated their last electrons, what happens to the materials?

In order for any technology to be sustainable, a full life cycle analysis (LCA) must be done to determine how it's made, how it's used, and where it goes when retired. Countless private and government stakeholders are exploring ways to increase the efficiency of renewable energy systems and discover new ways to recycle them when they're retired. Until circular economics are fully grafted into solar and wind generation, a disappointing amount of turbine and solar panel material will simply be thrown away.

It's mind-boggling to think something lauded as good for the planet can't be recycled. So where do turbine and solar panels go at the end of their lives, and why aren't they easily recycled?

Let's start with wind. After all, it's the biggest producer of renewable energy in the country.

Where do wind turbines go when they're taken down?

In Casper, Wyoming, a bizarre graveyard encapsulates both the promises and pitfalls latent in the shift away from fossil fuels. A 100 meter procession of 870 fiberglass turbine blades lay sprawled near the North Platte River. These blades, once driving the first generation turbines installed proudly in the 1990s, have reached the end of their life. They are slated to be cut into three sections, stacked, and buried in the Wyoming soil.

And there are more where that came from. Around two gigawatts of turbines will be replaced in 2019 and 2020, with the U.S. expected to replace around 8,000 blade sets in the next four years.

Around 85 percent of turbine components – copper, steel, and electronics – can be profitably recycled. But the massive fan blades present the greatest recycling challenge. As soon as they're taken off the turbine, the 100 to 300 ft blades are cut up on-site and delivered (expensively) by truck, to either a dump or recycling facility.

But it's hard to find any market for the fiberglass blades.

The composite fiberglass blades in first generation turbines are the most difficult part to recycle for two reasons: First, fiberglass is very difficult to recycle into a useful product, and second, the sheer mass of each blade makes it unmanageable and unworkable.

And that's why they end up at places like Casper, Wyoming. A lot of blades are simply being buried, an un-green end to a machine that existed to produce green energy.

And turbines are getting bigger. The world's largest turbine – the GE Haliade-X – sports 107 meter blades driving a turbine capable of 12mw output.

One report estimates by 2050, 2.9 million tons of blades will be thrown out globally each year, with 43 million tons of blades wasted cumulatively. Today's new turbines will be tomorrow's waste problem.

In the United States alone, 720,000 tons of blades will be disposed of in the next 20 years, and that doesn't include the newer blades that are much larger.

Still, another report estimates by 2050, all global blade waste will represent 0.015 percent of all municipal waste dumped in landfills in 2015 alone.

Considering this diminutive waste footprint, maybe trashing washed-up blades isn't such a bad option. In a single year, turbine blades are as little as 0.05 percent of what's going into landfills. To put it in perspective, ten times more weight in disposable plastic products go into dumps than turbine blades.

But for the legions of people and organizations trying to find better uses for old turbine blades, the recycling quagmire needs to be drained before larger blades and turbines reach the end of their lives.

Where do solar panels go when they're taken down?

We haven't quite hit the end-of-life waste problem of solar panels yet. Reason being, solar panels have a relatively long shelf life. Panels from the 70s and 80s are still working, and most solar panels only lose 6 to 8 percent of their efficiency after 25 years. But when current panels reach the end of their useful life (probably in the early 2030s), we'll have a big mess very quickly: Cumulative solar waste is expected to be up to 86 million tons by 2050. The United States is slated to cumulatively produce 7.5 million tons of solar waste by 2050, with around 6 million new tons being generated every year globally.

Like turbine blades, solar panels are challenging to recycle. Solar panels can't be recycled like other electronics. It could be easy to shrug their waste off as a casualty, a necessary evil in green development. But not only is ignoring the circular economy of renewable energy ironic, valuable materials could be extracted at end-of-life, further reducing the need for extractive processes when creating new renewable technology. Metals like lead and cadmium potentially leaching from solar panels in the landfill is another motivator in making sure they don't end up there in the first place.

Though there aren't any moving parts in a solar panel, their chemical components wear down over time (generally 20 to 30 years). Solar panels contain valuable materials like aluminum, silicon, and trace precious metals. When the panel gives up the ghost or doesn't produce adequately, it's very difficult to recover the valuable materials inside.

The panel itself is composed of multiple materials all sandwiched together, making extraction of pure material exceedingly difficult. Metal and glass have to be separated. The panel itself may be chemically treated, burned, or ground to recover materials. These processes are expensive, present environmental problems, and often create impure products.

The United States has zero recycling requirements for solar panels. A measly estimated ten percent of U.S. solar panels are recycled. A typical solar panel may score $3 in recoverable assets, but cost $12-$25 to recycle. Clearly, the economics don't add up. It's simply much cheaper to dump a panel, and it doesn't have the high-profile, high footprint optics that turbine blades do.

What are the solutions to recycling turbines and solar panels?

An unfortunate recent “documentary” arrives at the dismal conclusion that renewable energy causes more harm than good, and should be abandoned. But we can't stop building wind turbines and solar panels. Electricity production accounts for 31 percent of all global emissions. To avoid the potentially catastrophic impacts of climate change, energy has to decarbonize, fast. Many nations have vowed to produce only renewable energy by 2050. Wind energy is one of the cheapest, most effective ways to do this, with wind turbines offsetting their carbon footprint in less than six months.

And as wind and solar rapidly become more economically viable every year, market forces are certain to drive more and more of the production share to renewables.

The future of turbine recycling

Bar none, fiberglass blades are the immediate challenge to a sustainable wind industry. But there are useful products to harvest from retired blades just waiting for efficient recycling infrastructure. According to the American Wind Energy Association, 85 percent of turbine blade materials can be recycled. Several public and private research organizations are exploring ways to recover blade materials, with major interest in using recycled material in manufacturing new blades. One startup, Global Fiberglass Solutions, created a method to grind blades and condense them into pellets and board for walls and interiors. The company claims it can process 99.9 percent of a fiberglass blade, and processes 6,000-7,000 blades per year.

Mechanical processing into boards may be a challenge as there's currently little demand for such products. Pyrolysis (the process of gassifying a blade to extract valuable materials), may be a good option for newer carbon fiber blades, but this technology requires massive startup costs, and carbon fiber blades likely won't be decommissioned for at least a decade.

Extending blade longevity is the most important way to reduce blade waste. Evolution of monitoring and maintenance technology will likely produce greater lifespans for blades, thereby reducing waste. Turbine manufacturers are also improving the recyclability of blades. Vestas, on of the globe's largest turbine manufacturers, pledged to produce only zero-waste turbines by 2040.

Several innovative municipalities and firms are exploring ways to use blades in construction, infrastructure, landscaping, and art.

The future of solar panel recycling

Because most installed solar panels are still operational, recycling is lagging behind turbine recycling. Furthermore, it's impossible to extract valuable solar materials without expensive processes that produce impure materials. If valuable materials in solar panels like silver and silicon could be separated more efficiently, the profitability of recycling could be bolstered. Some recyclers and organizations are attempting to improve recycling processes to this end. The National Renewable Energy Laboratory is urging the development of recycling processes that recover valuable materials with maximum purity, rendering recycling as profitable as possible. If recycling is improved, the solar recycling industry could be worth $15 billion by 2050 and provide the raw materials for 2 billion new panels.

Conclusion

There's been significant protest recently over the wastefulness of renewable energy equipment that reach the end of their service. While laudable, many objections are ill-informed and even inconsequential when scrutinized with the facts. However, every effort must be made to reclaim as much material as possible from wind and solar technology. If the world is serious about reaching net zero carbon by 2050 and embedding sustainability in its value chains, solar and wind materials must be reintroduced into the circular economy in order to maximize the sustainability of tomorrow's clean energy production.