Downstream: End-of-life and recycling performance

Nickel's end-of-life system is the most mature of any material examined in this study.¹³⁶ Nickel retains its properties through repeated recycling, and its long-standing use in high-value applications such as stainless steel has supported the development of well-established collection and processing infrastructure over many decades.¹³⁷ Chart 33 shows that nickel’s collection rate is already high by the beginning of the projection period at 78% and remains essentially unchanged through to 2050, peaking at 79%, indicating a system operating close to its practical ceiling under current conditions.

Recycled material exceeds uncollected and disposed of material by a wide margin throughout the projection and continues to increase in absolute terms, reaching around one million tonnes more by 2050. However, two trends deserve closer attention. First, uncollected and disposed of material still triples over the projection periods, rising from 200 thousand tonnes in 2020 to 600 thousand tonnes by 2050. This occurs because a stable collection rate applied to an expanding end-of-life flow results in larger absolute losses each year. Second, post-collection losses increase more rapidly than recycled volumes, suggesting that processing inefficiencies become a progressively more important source of material loss, even in a highly mature recycling system.

Downcycling represents a distinctive downstream constraint, and one that conventional recycling indicators do not fully capture. Although the model records downcycled material separately, the underlying issue is that a significant share of nickel recovered from stainless steel is not returned to stainless steel production but instead becomes diluted within carbon steel. The metal is neither discarded nor lost to the environment, yet it is effectively removed from future nickel supply because it can no longer be economically recovered. This represents a loss of material function rather than material mass. The problem is particularly important for high-value applications, where battery-grade and specialty alloy nickel entering bulk steel production represents a permanent loss of quality despite remaining in the wider material system.

Chart 34 reflects the maturity of nickel’s recycling system. Old scrap has been the dominant source of secondary supply since the early 1990s, and its contribution continues to grow, reaching around three-quarters of total secondary supply by 2050 (around 1.7 million tonnes). New scrap remains an important secondary source but is progressively overtaken as increasing volumes of end-of-life material become available. This shift reflects the growing stock of products reaching retirement rather than any decline in the recovery of manufacturing scrap, which remains routinely recycled.

Chart 35 below highlights an important asymmetry. The End-of-Life Recycling Rate increased substantially over the historical period, rising from 25% in 1950 to 60% in the 2020 baseline year, but remains largely unchanged throughout the projection, reinforcing the conclusion that end-of-life recovery has reached a plateau. By contrast, the Recycling Input Rate, which stands at 25% in 2020, dips slightly after the baseline year before rising steadily during the later decades to reach 37% by 2050. Unlike some of the other materials examined, this improvement does not primarily reflect declining primary supply. Instead, it indicates that secondary supply is growing faster than total demand, representing a genuine improvement in recycling rather than an artefact of scarcity.

Taken together, these results suggest that nickel's remaining circularity potential lies less in collecting more material and more in improving what happens after collection. Reducing post-collection losses, and above all, returning recovered nickel to applications that preserve its material quality rather than diluting it into bulk steel represent the greatest opportunities to strengthen nickel's long-term circularity.