The stakes are considerable. The EU Green Deal commits member states to cutting greenhouse gas emissions by 55 percent by 2030 and achieving climate neutrality by 2050, goals that hinge on scaling up renewable energy and battery technologies as fossil fuels are phased out. Under the Critical Raw Materials Act, the bloc aims by 2030 to raise domestic extraction, production and recycling of these metals and minerals to at least 10, 40 and 25 percent of annual European consumption respectively, while ensuring no critical raw material relies on a single non-EU country for more than 65 percent of its processing. Recycling alone, however, will not keep pace with surging global demand in the short term, meaning primary extraction — an activity often associated in the public mind with environmental degradation and ethical dilemmas — will remain central to the strategy. That tension makes public dialogue about supply chains, import reliance and mining impacts not merely desirable but urgent.

The researchers chose an unlikely laboratory for this conversation: the festival field. Informal education settings such as arts, cultural and science festivals offer dynamic environments where leisurely audiences can encounter technical concepts without the framing of a classroom, and previous research shows such audiences prize high levels of interactivity, hands-on participation and relaxed conversation with experts. The catch is time. For an engagement to work in a fast-paced festival setting, it must consume as little of the visitor’s time as possible while remaining attractive, informative, stimulating and fun. The team therefore set three objectives: create an eye-catching experience for potentially incidental audiences, promote genuine learning about the links between critical raw materials, decarbonisation and supply risk, and design an evaluation strategy concise enough to be, in their words, festival-friendly.

Development proceeded through three iterative phases of scoping, testing and refinement, each grounded in real-world field data. The scoping phase began at two Irish festivals: Féile na Bealtaine, a rural arts festival in Dingle, County Kerry, and the urban Cork Carnival of Science. Surveys of 32 participants in Dingle revealed high self-reported awareness of the topic overall, but notable weakness on the definition of critical raw materials and their connection to the Green Deal. When asked how they wanted to learn, 76 percent chose hands-on tasks and 66 percent wanted visual examples of the materials themselves. Open feedback echoed these preferences, with most respondents emphasising interactivity, creativity and visual stimulation, alongside a desire to understand how raw materials connect to daily life and supply chains.

Those responses shaped the first prototype, called Shopping to Decarbonise, a tabletop activity in which participants shopped for up to four key critical raw materials to build a solar panel and a wind turbine. Fifteen cubes representing different elements sat atop a periodic table, each carrying images of the pure metal or common ore and plain-language prompts about its uses — neodymium, a key material for wind energy, bore the clue spinning magnets equal electricity, while dysprosium’s prompt read maintains magnetic abilities. Trials at the Cork Carnival of Science with 22 participants confirmed the concept’s appeal but exposed a practical flaw: half of the participants dropped out before completing the 20-minute engagement and exit survey, signalling that the whole interaction simply took too long.

The testing phase transformed the prototype into GreenDealz, complete with a supermarket-style logo and a periodic table rebranded as Aisle 2050. The cubes gained barcodes so practitioners could act as cashiers, scanning shopping answers via mobile app, and import reliance data was woven into the experience through country-of-origin style labels on each cube. The number of cubes was trimmed to ten to respect festival time constraints, and a difficulty-based shopping score was introduced, awarding points for prompts rated easy, moderate or hard depending on how much critical thinking was needed to link a material to its technology. Tested at the National Ploughing Championships in County Laois — an agricultural festival drawing roughly 250,000 visitors over three days — the rebranded toolkit held attention with zero observed dropouts among the 40 consenting study participants, many of whom lingered to discuss the topic further.

Evaluation, however, proved the hardest nut to crack. A quick three-minute pre-and-post online quiz disrupted the natural flow of the engagement, and the three true-or-false knowledge items used showed reliability far below acceptable thresholds, failing to detect meaningful change. The team’s solution in the refinement phase was to embrace embedded assessment, an approach in which the evaluation tasks closely match the learning tasks of the activity itself. Three tasks were built from existing GreenDealz props: participants placed cubes representing everyday items containing critical raw materials into a basket, used cubes on a weighing scale to indicate how many times more mineral resources an onshore wind farm requires compared with a gas-fired power plant, and estimated how many of the EU’s 49 critical and strategic raw materials have import reliance above 75 percent. Scores were expressed as a ratio out of a maximum of 65.

The results were striking. Using a quasi-experimental design across three Science Week events in Ireland, the team compared GreenDealz against a control activity in which participants matched rock and ore samples to a geological map of Ireland. Baseline knowledge scores were statistically equivalent between the two groups, hovering around 0.54 to 0.58. After engagement, the intervention group’s scores jumped significantly to 0.84, a mean difference of 0.266 with a large effect size, while the control group showed no change at all. Field observations added a qualitative dimension: the embedded tasks maintained conversation between practitioner and participant, streamlined the interaction and even evoked a sense of playfulness. For the researchers, this suggests embedded assessment may be a more appropriate way to measure the effects of public engagement in festival settings than traditional survey techniques, which are vulnerable to social desirability bias and prone to interrupting the experience they are meant to evaluate.

The pooled shopping scores offered further insights into how people interacted with the material. Most participants correctly identified the materials with the easiest prompts — 90 percent chose silicon for solar panels and 72 percent chose neodymium for wind turbines — but far fewer spotted the harder connections, with only 18 percent selecting gallium for solar and 25 percent choosing dysprosium for wind. Instead, many gravitated toward lithium and titanium, materials made familiar by the battery age and popular culture respectively, hinting at how relevance and prior exposure shape engagement with geoscience. Crucially, participants working in groups achieved significantly higher shopping scores than those engaging alone, suggesting that discussion during decision-making drives deeper critical thinking — a promising finding for festivals, where people typically attend and participate in social groups, and where conversations sparked at the exhibit may ripple outward into wider social networks.

The authors are candid about the study’s limits: sample sizes were modest, participants skewed highly educated, and findings from an Irish context may not generalise to other countries or populations. Yet GreenDealz, in its current form, is a budget-friendly toolkit whose materials and guidance are publicly available, ready for practitioners who wish to open conversations about the materials behind the green transition. The team envisions future iterations ranging from full-scale gamified shopping experiences at large festivals to digital, self-paced versions, and stresses that rigorous testing of the toolkit’s broader effectiveness is the natural next step. For now, the pilot stands as a template for a pressing problem: if Europe is to mine, process and recycle its way to climate neutrality, the public deserves a seat at the table — and sometimes the most effective way to invite them is with a shopping basket, a barcode scanner and an aisle named 2050.

Subject of Research: Public engagement with critical raw materials and the EU Green Deal through an informal education toolkit

Article Title: Development of GreenDealz: a public engagement toolkit addressing critical raw materials and the EU Green Deal at informal education settings

Article References: Blennerhassett, L. C., Schuitema, G., & McAuliffe, F. (2026). Development of GreenDealz: a public engagement toolkit addressing critical raw materials and the EU Green Deal at informal education settings. Geoscience Communication, 9(2), 161-183. https://doi.org/10.5194/gc-9-161-2026

Image Credits: AI Generated

DOI: 10.5194/gc-9-161-2026

Keywords: critical raw materials, EU Green Deal, public engagement, science communication, informal education, festivals, geoscience, embedded assessment, renewable energy, supply risk, GreenDealz, Ireland

The stakes are enormous. The global photovoltaic glass market was valued at €14.4 billion in 2023 and is projected to reach €205 billion within eight years, growing at a compound annual rate of 30 percent. Some projections suggest global demand for PV glass could reach 200 million tons over the coming decades, and that PV glass volumes could exceed 100 million tons by 2034. Yet despite this weight, glass is among the least valuable materials recovered from a retired panel, worth only €0.1 to €1 per kilogram in Europe. That mismatch, high volume but low value, has long made solar glass recycling economically fragile, especially in the absence of large-scale recycling infrastructure and with high transport and processing costs eating into any margin.

To understand where the money actually goes, the researchers built a bottom-up cost model of a virtual 1-gigawatt glass recycling factory, adapting a framework originally developed for crystalline silicon manufacturing and updating it with current industry data drawn from IEA reports, vendor quotations, and supplier catalogs. The model tracks every step of the recycling chain, from collection and transport over a 100-kilometer distance to disassembly, glass separation, size reduction, washing, chemical or thermal treatment, and emission control. The result is a minimum sustainable price, the price at which the recycling operation can cover its costs without subsidy. Under low, average, and high cost scenarios, that price came out at $20.25, $25.78, and $30.27 per square meter of glass, respectively, with capital expenditures of €111 million and operating expenditures of €3.48 million for the reference plant.

The sensitivity analysis, conducted as a one-at-a-time perturbation of each cost factor at 0, 2, and 5 percent levels and visualized in tornado diagrams, revealed a clear hierarchy of cost drivers. Chemical or thermal treatment, washing and purification, emission control, size reduction, and transport emerged as the dominant contributors to the minimum sustainable price, a ranking that remained consistent across all perturbation levels. This finding matters because it tells engineers and policymakers exactly where to aim. If recycling plants can be sited within 50 to 100 kilometers of collection points, transport costs shrink; if washing and thermal treatment can be made more efficient, the largest single cost blocks erode. The authors note that the approach captures only first-order sensitivities and does not model interactions between parameters, so it should be read as a ranking of key cost levers rather than a full uncertainty analysis.

The more striking result comes from the learning-curve projections. Applying learning rates of 10, 15, and 20 percent, corresponding to conservative, base, and optimistic scenarios of technological improvement, to the cumulative growth of EU installed capacity, the researchers projected how recycling costs might fall as volumes scale. The answer: recycling costs could drop by up to $7 per square meter as deployment scales toward 4 terawatts, based on current recycling infrastructure and technologies. That trajectory echoes what has happened in photovoltaic manufacturing itself, where decades of learning drove module prices down by orders of magnitude. It also aligns with earlier findings that large-scale recycling plants can achieve low-cost recycling while small-scale facilities face multidimensional economic limitations, and that localized recycling with short transport distances can be both economically viable and environmentally sound.

But cost is only half the story. The other half is volume, and here the study delivers its most eye-catching numbers. Using a dynamic, cohort-based material flow analysis, the researchers treated Europe’s installed PV capacity as an in-use material stock and modeled its retirement with Weibull lifetime distributions at characteristic lifetimes of 25, 30, and 32 years. Three deployment scenarios were projected to 2050: a worst case in which installations hold steady at roughly 65 gigawatts per year, a moderate case aligned with the EU Green Deal reaching 3.5 terawatts with 9 percent exponential growth, and a best case doubling that ambition to 7 terawatts with about 12 percent growth. Converting retired capacity to glass mass at an intensity of 70 kilotons per gigawatt, within the traditional range derived from module weight and power density, the team calculated annual glass availability through 2070.

The projections are sobering. Under the worst-case and moderate scenarios, Europe will generate between 5 and 10 million tons of PV glass per year through 2070, while the best-case scenario could see availability rise to between 5 and 23 million tons annually from 2040 onward. Shorter module lifetimes produce more glass waste sooner; longer lifetimes delay and smooth the flows. A linear robustness check confirmed the overall pattern, with the moderate scenario showing a sharp surge in glass waste after 2040. The cohort-driven analysis even hints at a slowdown after 2070, as installation cohorts peak and shrink. For context, the EU currently collects about 12 million tons of glass packaging per year for recycling, against a 75 percent collection target by 2030. The PV industry alone could rival that entire stream, overwhelming infrastructure that was never designed for it.

The implications ripple outward from waste management to geopolitics. Europe currently imports up to €15 billion in green energy products annually, mainly from China and India, and a functioning circular PV industry could reduce that dependence while creating jobs and revenue. Glass production is also energy-intensive, responsible for more than 86 million tons of annual CO2 emissions globally, so recycling PV glass into new modules would cut both resource extraction and emissions, supporting Sustainable Development Goal 7 for clean and affordable energy. The authors argue that existing frameworks such as the WEEE Directive provide a regulatory foundation, but that scaling to multi-terawatt deployment will require targeted investment in recycling capacity, improved collection systems, deposit-return schemes, strengthened extended producer responsibility, and digitalized tracking ecosystems, aligned with the European Green Deal and the Circular Economy Action Plan.

The study is candid about its limitations. The cost model relies on global average data adjusted to European conditions, and because it was adapted from a silicon PV recycling framework, it may not fully capture the specific characteristics of perovskite materials, the emerging technology whose glass-glass encapsulation the analysis targets. The one-at-a-time sensitivity method ignores parameter interactions, and the authors recommend future work using variance-based and Monte Carlo approaches, country-specific data, and extensions to aluminum and other module materials. Still, the core message stands with unusual clarity: a wave of millions of tons of glass is coming to Europe within a decade, and whether it becomes a landfill burden or a domestic resource depends on decisions made now. Subsidies, feed-in tariffs for recycling, public-private partnerships, and recycling startups could tip the economics, ensuring that the material backbone of the solar transition is itself part of the transition, cycled again and again through the value chain rather than discarded at its end.

Subject of Research: Techno-economic analysis and material flow projection of photovoltaic glass recycling in Europe

Article Title: The coming photovoltaic glass wave: techno-economic sensitivity, learning effects, and material flow insights

Article References: Shahzad, U., & Peters, I. M. (2026). The coming photovoltaic glass wave: techno-economic sensitivity, learning effects, and material flow insights. Journal of Industrial Ecology, 30(4), 1971-1984. https://doi.org/10.1007/s44498-026-00134-9

Image Credits: AI Generated

DOI: 10.1007/s44498-026-00134-9

Keywords: photovoltaic glass, solar panel recycling, circular economy, material flow analysis, Weibull distribution, learning rate, perovskite solar modules, EU Green Deal, WEEE Directive, cost modeling, sustainability, renewable energy