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Environmental innovations heavily depend on government policies and consumers’ behaviour. This paper addresses the issue of how these two factors interact in shaping the transition to a green technology. We extend models of technological selection with heterogeneous agents and learning by including a weak hierarchy between green and polluting goods. For general distributions of agents’ income and the explicit inclusion of a carbon tax, the model is not analytically tractable so we derive our results using numerical simulations. Given the level of income, carbon taxes are more effective when technological improvements brought about by wealthy pioneer consumers suffice in inducing the remaining population to buy the green good. In this case, a negative relationship between income inequality and tax effectiveness emerges. Taxes on polluting production have a regressive effect since they are mainly paid by poorer people who consume less of the green good. For these people, a negative wealth effect strongly contrasts the standard substitution effect of the tax. Finally, both lower inequality and taxes have the expected effect for intermediate levels of the learning parameter.