In this paper we show that carbon pricing is subject to time-inconsistency and we investigate solutions to improve on the problem and restore the incentive for the private sector to invest in low-carbon innovation. We show that a superior price- investment equilibrium can be sustained in the long-term, if the policy-maker is enough forward looking and allowed to build reputation. In the short-term, time- inconsistency can be alleviated by complementing carbon pricing with project-based carbon price guarantees.