Rim Mansouri

Type of the article: Research Article

Abstract
The environmental and economic benefits of voluntary firm-level practices are often assumed but rarely tested, particularly with respect to firm-level heterogeneity in developing economies. This study aims to estimate the effect of two voluntary environmental practices (energy management and CO2 emissions monitoring) on firm productivity in Morocco, and to test whether these effects vary across the productivity distribution. Using firm-level microdata from the 2023 World Bank Enterprise Survey on 598 Moroccan manufacturing and service firms, conditional quantile regressions and quantile treatment effects with propensity score matching are employed to address heterogeneity and potential endogeneity. The results show that energy management practices increase productivity by 33% and CO2 monitoring by 57% on average. However, these average effects mask substantial heterogeneity. At the 10th percentile, energy management yields a 9.6% gain while CO2 monitoring has no significant effect. At the 50th percentile, energy management yields a 46.4% increase, while CO₂ monitoring yields a 61.2% increase. At the 90th percentile, energy management yields 28.4% and CO2 monitoring 61.7%. Quantile treatment effects confirm this heterogeneity but reveal that energy management benefits mid-to-upper performers (30th–70th percentiles), whereas CO2 monitoring benefits primarily low-performing firms (10th–20th percentiles). These findings indicate that the impact of voluntary environmental practices is context- and firm-specific. Policy implications suggest that differentiated support strategies are required to enhance both environmental and economic performance in developing economies.

Acknowledgments
We are grateful to Mohammed V University of Rabat, the Faculty of Law, Economics and Social Sciences – Agdal (FSJES-Agdal) and the Laboratory of Applied Economics for their institutional support.
This work was supported by the Centre National pour la Recherche Scientifique et Technique (CNRST).