[en] Does a trade-off exist between energy efficiency and economic growth? This question underlies some of the tensions between economic and environmental policies, especially in developing countries that often need to expand their industrial base to grow. This paper contributes to the debate by analyzing the relationship between energy efficiency and economic performance at the micro- (total factor productivity) and macro-level (countries' economic growth). It uses data on a large sample of manufacturing firms across 29 developing countries to find that lower levels of energy intensity are associated with higher total factor productivity for the majority of these countries. The results are robust to a variety of checks. Suggestive cross-country evidence points towards the same relation measured at the macro-level as well. - Highlights: •Total factor productivity is an accurate proxy of technological change. •Energy efficiency triggers total factor productivity especially in manufacturing. •Technological change via energy efficiency in manufacturing is an engine of growth.