A study by Professor Yihsu Chen at the University of California Merced has found that a cap-and-trade system is more likely than a carbon tax system to trigger the adoption of clean energy technologies. The study, which was coauthored by Chung-Li Tseng of the University of New South Wales in Australia and that is published in the Energy Journal Volume 32, Number 3, 2011 (a quarterly journal of the International Association for Energy Economics) also found that the volatile pricing of a cap-and-trade system could lead to earlier adoption of clean technology by firms looking to hedge against carbon cost risks.
The study used economic models based on a framework of real options to determine the optimal timing for a coal-burning firm to introduce clean technologies using the two most commonly considered policies: (1) cap-and-trade, in which carbon emissions are capped and low-emission firms can sell excess permits to high-emission firms; and (2) carbon taxes, which employ a fixed monetary penalty for per-unit carbon emissions.
According to Professor Chen, “…cap-and-trade offers ‘carrots’ while taxes offer ‘sticks’. Cap-and-trade induces firms to explore profit opportunities, while taxes simply impose penalties to turn clean technology into a less costly option.”
For the study, researchers considered the scenario of a small firm that owns a coal-fired power plant and is obliged to supply power to its customers. They compared cap-and-trade and carbon tax models in determining when the firm would choose to add a natural gas power plant – a relatively clean energy resource – in order to meet its energy demands while maximizing its long-term profits. The study found that the cap-and-trade model triggered the adoption of clean energy technology at a lower overall carbon price than a tax policy did. Further, the study found that the volatility of non-fixed permit prices was the key difference that led the firm to add a natural gas plant earlier than it would have under a more predictable tax system. Professor Chen said that: “Based on our study, mechanisms designed to reduce cap-and-trade permit prices or suppress price volatility — which have been implemented in existing cap-and-trade programs like the Regional Greenhouse Gas Initiative — are likely to delay clean technology investments.”