The circularity gap in the clean energy transition pathway endangers our net zero 2050 and climate goals. Without considering the environmental impact of renewable technologies, we risk creating a significant waste problem and potential emissions in the near future. Strategic planning, efficient recycling systems, and using sustainable materials are crucial to address this gap and ensure a sustainable energy transition, writes MaREI's Lala Rukh Memon.
“The success of the energy transition depends on a transformation of the global energy sector from fossil-based to zero-carbon sources by the second half of this century, reducing energy-related CO2 emissions to mitigate climate change and limit global temperature to within 1.5° of pre-industrial levels,” says IRENA Energy Transition Outlook. Let’s inspect these zero-carbon sources from a circularity perspective and explore their impacts in the next two decades.
As the world races progressively towards tapping more energy from renewable resources, the importance of a circular economy approaches in the clean energy transition cannot be denied if the aim is to achieve net zero emissions.
The embodied carbon in materials for technologies production such as solar, wind, lithium-ion batteries, and retrofitting techniques essentially adds up in the net zero equation. But do we consider it? Some of these technologies have a lifespan of 20 to 30 years, meaning an addition of today shall be scrapped by 2050. That is when we promise to have been striking a balance between emissions.
A significant and concerning gap exists between the circularity principles necessary for sustainable development and the current trajectory of the clean energy sector.
Reduce, reuse, and recycle
The pathway to energy transition fails on the fundamental 3R principles of circular economy: reduce, reuse, and recycle. Reducing the number of solar panels, wind turbines, and batteries is undoubtedly out of the question. Reusing these technologies is not an option once they have reached the end of their life. Recycling is not yet technically possible or feasible.
Nevertheless, by applying circularity principles, production impact can be reduced by narrowing the use of both energy and materials. The life expectancy can be increased by designing robust products that can be repaired, refurbished, and remanufactured. Implementing efficient recycling systems can close resource cycles, thereby mitigating the adverse impacts of human toxicity and enhancing the recovery of valuable materials.
Unveiling the carbon footprint in disguise of the ‘zero-carbon sources’: solar, wind, energy storage (batteries), critical materials, and retrofitting techniques (material):
Solar PV
With 243 GW addition of Solar PV capacity, the world reached a whopping 1.1 TW capacity. On average solar panels have a capacity of about 400W; counting both rooftops and solar farms, there are as many as three billion functioning solar panels.
Figure: Solar PV Global Capacity and Annual Additions, 2012-2022. Source: https://www.ren21.net/wp-content/uploads/2019/05/GSR-2023_Energy-Supply-Module.pdf
A typical solar panel’s life is about 25 to 30 years. Eventually, these billions of solar panels and many more will reach the end of their life around the second half of this century, which is when we hope to have achieved net zero and decarbonised much of the energy sector. Are solar panels an eco-disaster waiting to happen? asks the BBC.
Circularity was certainly not one of the objectives when solar panels and wind (tidal) turbine blades were initially designed. But now, as the first generation of domestic solar panels is coming to the end of their usable life and the Earth edges closer and closer to its overshoot day, the complexity of recycling the valuable materials (copper, silicon and silver) involved in the design is becoming a subject of concern.
Earth Overshoot Day is when humanity’s demand for ecological resources and services in a given year exceeds what Earth can regenerate.
Figure: Earth Overshoot Day 1971-2023. Source: https://www.overshootday.org/newsroom/press-release-june-2023-english/
The urgency to address this issue stems from the fact that the global economy is now only 7.2% circular, and it’s getting worse year on year – driven by rising material extraction and use.
Recovering precious materials from solar panels is a painstaking process. Thus, an efficient and economically viable extraction method shall be a game changer. Such a method shall also motivate the recycling of glass fronts and aluminium frames.
The life cycle analysis of the materials involved in concentrating solar thermal power (6.3 GW) and solar thermal heating (22.8 GWth) global capacity is another wakeup call for starting to work on the circularity gap of our net zero pathway and think about The Climate Question – How renewable are renewables?
Wind and tidal turbines
The gigantic wind turbine blades, built to withstand hurricane-force winds, can’t be hauled away at the end of their lifespan. A diamond-encrusted industrial saw is required to break the blades into pieces before they can be transported for further repurposing.
The wind power projects of today exhibit turbine capacities ranging from 3 to 4 MW onshore and a more substantial 8 to 12 MW offshore. These account for the total grid-connected installed wind capacity of 829GW in 2021 and 530MW from wind and tidal energy.
Across the globe, thousands of retired blades are being dismantled from steel towers, and unfortunately, most of them end up in landfills. In the US alone, abouty 8,000 blades are scheduled for removal annually over the next four years.
Having grappled with this issue for a longer period, Europe anticipates the disassembly of about 3,800 blades each year until at least 2022 (according to the most up-to-date information available). The situation is projected to worsen as most of these blades were constructed more than a decade ago when wind turbine installations were less than one-fifth of their current levels.
In the US, they go to the handful of landfills that accept them, in Lake Mills, Iowa; Sioux Falls, South Dakota; and Casper, where they will be interred in stacks that reach 30 feet under, destined to be there forever.
Figure: Fragments of wind turbine blades await burial at the Casper Regional Landfill in Wyoming, USA. Source: https://www.bloomberg.com/news/features/2020-02-05/wind-turbine-blades-can-t-be-recycled-so-they-re-piling-up-in-landfills
Apart from fibreglass blades, the majority of turbine components, steel, copper wire, electronics and gearing can be recycled or reused. The transportation cost of some blades as long as a football field is one of the bottlenecks. The good news is scientists and researchers globally are trying to find better ways to repurpose these into bridges, benches, and cycle shades.
Siemens Gamesa (a leader in the renewable energy industry) has commenced the deployment of novel materials in its turbine blades, enhancing their recyclability.
Batteries
Batteries, and components containing critical raw materials, are a key focus in developing circular economy strategies. The critical raw materials – including lithium, cobalt and graphite – are required for the batteries to be used for storing power from solar and wind and also for electric vehicles.
Throughout the life cycle of electric vehicles, batteries contribute significantly to their environmental footprint. The extraction of materials like lithium, sourced from delicate and distinct ecosystems, poses environmental challenges.
Figure: ‘Lithium Fields’ in the Salar de Atacama salt flats in northern Chile. Source: https://www.tomhegen.com/collections/the-lithium-series-i
The breathtaking colour-filled picture from South America shows the dark side of our electrifying world swiftly moving towards net zero. Similarly, materials such as cobalt present social risks associated with mining, including such topics as child labour and conflicts.
Environmentally responsible recovery and recycling is essential for recovering valuable resources from discarded electric vehicle batteries, as they present difficulties in terms of fire risks and hazardous contamination.
In an ideal scenario, calculations suggest that recycling end-of-life electric vehicle batteries could meet about 60% of the global demand for cobalt, 53% for lithium, 57% for manganese, and 53% for nickel by 2040. But the recycling processes and regulation are still developing electric vehicle batteries, which is different from lead acid batteries.
The European Union’s extended producer responsibility and regulations in China, Japan and India specifically target EV batteries. However, a lack of an effective policy exists globally, like many other net zero and climate targets.
Critical materials
Energy transition shall create a boom in demand for critical materials (minerals and metals). The International Renewable Energy Agency’s (IRENA) 1.5°C scenario highlights the extensive scale of the energy transition infrastructure and critical materials required for climate stabilisation.
There is already an evident imbalance between the supply and demand for several minerals, with lithium experiencing exceptionally high levels of demand. While energy security remains relatively unaffected, disruptions in the supply of critical materials have a disproportionately large impact on the progress of the energy transition.
The risks and supply dynamics associated with critical materials differ significantly from those of fossil fuels due to their distinct characteristics and patterns.
One major concern is that during the energy transition phase, there is a trading dependency on fossil fuels for dependency on critical materials. Although abundant reserves for minerals are required in the energy transition, the mining and refining capabilities for these minerals are constrained. Market limitations are expected to arise in the short to medium term, primarily due to inadequate investment in upstream activities.
If properly strategised and implemented, a shift towards renewable energy can redefine the historical impact of extractive industries and associated communities. Throughout history, extractive industries have been associated with various risks to local communities, including violations of labour and human rights, deterioration of land, depletion and pollution of water resources, and air pollution.
Despite the current awareness and standards, these risks still persist. The critical materials are housed in energy assets with a typical lifespan of 10 to 30 years. They are technically reusable and recyclable after end of life, unlike fossil fuels which are burnt immediately.
By establishing efficient recycling systems and promoting responsible sourcing practices, we can create a more resilient and sustainable supply of critical materials. Furthermore, circularity in critical materials can enhance resource security and reduce dependency on uncertain global supply chains.
Retrofitting techniques (material)
Built environment upgrades to incorporate energy conservation and efficiency measures reduce operational carbon emissions of buildings. However, retrofitting techniques also have an embodied carbon component, which refers to the carbon emissions associated with the manufacturing, transporting, and installing of building materials and components during the retrofit process.
These emissions are released upfront and are typically attributed to the retrofitting phase of a building’s life cycle. If the embodied carbon associated with retrofitting is high, it can offset some of the environmental benefits gained from operational energy savings. Additionally, if retrofitting requires extensive demolition and reconstruction, it can lead to additional carbon emissions.
To minimise the negative impact of retrofitting, it is important to prioritise sustainable and low-carbon building materials and construction practices at the beginning. This can include using recycled or locally sourced materials, choosing energy-efficient products, and optimising transportation logistics to reduce emissions.
Additionally, incorporating life cycle assessment approaches can help assess and minimise the overall carbon footprint of retrofitting projects.
Conclusion
The energy transition is crucial to make global efforts towards mitigating climate change. However, the concept of net zero and achieving climate objectives cannot overlook the challenges posed by embodied carbon in developing and expanding renewable energy technologies.
As materials involved in built environment retrofitting techniques, solar panels, wind turbines, and batteries approach the end of their lifespan, the issue of circularity becomes apparent.
Circularity principles, such as reducing, reusing, and recycling, play a vital role in addressing the environmental impact of these technologies. The recovery of valuable materials from solar panels, the repurposing of wind turbine blades, and the responsible recycling of batteries are essential steps towards closing resource cycles and minimising waste.
However, there are significant gaps in the circularity principles applied to the clean energy sector. The recycling processes for these technologies are still developing, and the lack of effective global policies and regulations hinders progress.
Additionally, the booming demand for critical materials required in the energy transition raises concerns about supply dynamics and potential market limitations. The circularity gap in clean energy transition pathway endangers our net zero 2050 and climate goals.
To overcome challenges, strategic planning and implementation are necessary. This involves designing robust products with extended life expectancy, establishing efficient recycling systems, investing in research and development for recycling technologies, and promoting the use of sustainable and low-carbon materials in retrofitting projects.
By addressing the circularity gap in the net zero pathway, we can ensure that the renewable energy sector reduces operational carbon emissions and minimises the environmental impact associated with the production and disposal of renewable technologies.
A comprehensive and sustainable approach to the energy transition is essential for achieving long-term climate goals while considering the full lifecycle of these technologies and involved materials.
Author: Lala Rukh Memon (LinkedIn) is a doctoral researcher at MaREI–Science Foundation Ireland Research Centre for Energy, Climate and Marine Research and Innovation. She is working on Energy Performance Contracting (EPCs) framework for energy transition into the built environment. She is an electrical engineer and has a double master’s in energy systems and marine plastics abatement. Apart from conventional education, she participated in a summer school at Robinson College – University of Cambridge (2022), participated in (Physics) Nobel Laureates Meeting in Lindau, Germany (2019), worked at Coventry University (2018), studied one semester in the United States for a cultural exchange programme-Global UGRAD (2015).
References
1) https://www.irena.org/Energy-Transition/Outlook
2) https://www.ren21.net/wp-content/uploads/2019/05/GSR-2023_Energy-Supply-Module.pdf
3) https://futureearth.org/2022/12/16/circular-economy-and-the-clean-energy-transition/#:~:text=The%20circular%20economy%20has%20been,fueled%20by%20renewable%20energy%20sources.%E2%80%9D
4) https://twitter.com/BBCWorld/status/1665290298199515138
5) https://www.genevaenvironmentnetwork.org/resources/updates/earth-overshoot-day/
6) https://www.circle-economy.com/
7) https://www.bloomberg.com/news/features/2020-02-05/wind-turbine-blades-can-t-be-recycled-so-they-re-piling-up-in-landfills Dunn, J, Slattery, M Kendall, A, Ambrose, H & Shen, S Environ. Sci Technol. 55, 5189–5198 (2021)