Endogenous growth and natural resource scarcity

Endogenous growth theory has rekindled interest in the role of innovation in determining long-term economic growth. Generally, this body of literature has ignored the contribution of natural resources to growth or the role of innovation in overcoming resource scarcities. The latter problem has been a focus of resource economics for many years, but innovation is usually modelled as exogenous rather than endogenous technological change. Recent investigations in political economy have additionally suggested that the 'supply' of innovation may itself be constrained by resource scarcities, especially in the developing world. The following paper attempts to bridge these theoretical gaps through the formal analysis of two issues: First, a simple 'Romer-Stiglitz' model of endogenous growth with resource scarcity and population growth is developed to determine the optimal 'balanced' growth path for the economy. Second, the basic model is extended to allow for the possibility of resource availability constraining the supply of innovation, so that in the long run innovation net of any resource constraint is zero. However, under the latter conditions it is still possible to avoid resource exhaustion and thus achieve a constant level of per capita consumption in the long run. The paper therefore demonstrates that endogenous growth can overcome resource scarcity, but the outcome in the long run depends critically on assumptions concerning any constraints imposed by resource availability on the generation of innovation.