成長の限界再考：拡張World3枠組みにおけるエネルギー転換と循環経済の統合

Unofficial AI-generated summary based on the public title and abstract. Not an official translation.

🔬研究者:エネルギー転換と循環経済の相互作用をシステムダイナミクスで定量化する手法と、資源制約下での限界を理解するための枠組みを提供する。

🏢実務担当者:自社の脱炭素戦略や循環経済への取り組みが、資源制約下で長期的にどの程度有効かを評価する際の視点を提供する。

🏛政策担当者:エネルギー転換と循環経済を個別に推進するだけでなく、両者のトレードオフを考慮した統合的政策設計の必要性を示唆する。

The 1972 study The Limits to Growth highlighted the risk of systemic overshoot and steep decline due to resource constraints, but was criticized for underestimating technological adaptation. This paper revisits that thesis by extending the World3 model to incorporate two major contemporary transformation strategies: the energy transition (ET) towards renewable energy sources and the circular economy (CE). It asks to what extent combined CE and ET strategies alter overshoot-and-collapse dynamics and whether they can prevent, rather than merely delay, systemic decline. To enable this analysis, the aggregated stock of non-renewable resources is disaggregated into distinct energy and material flow components. The CE module represents material life cycles, including durability constraints and a maximum recyclability rate of 90%. The ET module simulates renewable energy expansion under economic, environmental, and resource feedback constraints. Under the World3 model structure and the selected scenario assumptions, the results indicate that CE and ET individually delay systemic decline, but do not prevent it within the explored parameter space. Instead, resource pressures shift between the energy and material domains. The ET pathway alleviates the depletion of fossil energy, but accelerates the material demand for renewable infrastructure. In contrast, CE reduces primary material extraction but increases energy requirements. The combined CE & ET scenario exhibits the highest resilience, extending population stability and industrial output relative to the individual strategies. However, the system’s fundamental overshoot-and-decline dynamics persist. More broadly, the simulations should be understood as exploratory scenario experiments rather than predictive forecasts. These findings reaffirm the core message of the original study under the assumptions explored here: technologies and efficiency-oriented strategies alone are insufficient when continued exponential growth on a finite planet outweighs gains in resource productivity. This study contributes to the cleaner production literature by quantifying rebound effects, burden shifting, resource-efficiency limits, and energy–material trade-offs within an integrated system dynamics framework.

• openalex https://doi.org/10.1016/j.jclepro.2026.149387first seen 2026-10-02 04:39:33