A carbon tax as well as carbon emission trading is used within the carbon price concept. Two common economic alternatives to carbon taxes are tradable permits with carbon credits and subsidies. In its simplest form, a carbon tax covers only CO2 emissions. It could also cover other greenhouse gases, such as methane or nitrous oxide, by taxing such emissions based on their CO2-equivalent global warming potential.[6] Research shows that carbon taxes do often reduce emissions.[7] Many economists argue that carbon taxes are the most efficient (lowest cost) way to tackle climate change.[8][9] As of 2019[update], carbon taxes have either been implemented or are scheduled for implementation in 25 countries.[10] 46 countries have put some form of price on carbon, either through carbon taxes or carbon emission trading schemes.[11]
Some experts observe that a carbon tax can negatively affect public welfare, tending to hit low- and middle-income households the hardest and making their necessities more expensive (for instance, the tax might drive up prices for, say, petrol and electricity[12]). Alternatively, the tax can be too conservative, making "comparatively small dents in overall emissions".[13] To make carbon taxes fairer, policymakers can try to redistribute the revenue generated from carbon taxes to low-income groups by various fiscal means.[14][15] Such a policy initiative becomes a carbon fee and dividend, rather than a plain tax.[16]
^Bashmakov, I.; et al. (2001). "6.2.2.2.1 Collection Point and Tax Base". In B. Metz; et al. (eds.). Policies, Measures, and Instruments. Climate Change 2001: Mitigation. Contribution of Working Group III to the Third Assessment Report of the Intergovernmental Panel on Climate Change. Print version: Cambridge University Press, Cambridge, UK, and New York, N.Y., U.S.A.. This version: GRID-Arendal website. Archived from the original on 28 December 2013. Retrieved 8 April 2011.
^Gupta, S.; et al. (2007). "13.2.1.2 Taxes and charges". Policies, instruments, and co-operative arrangements. Climate Change 2007: Mitigation. Contribution of Working Group III to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change (B. Metz et al. Eds.). Print version: Cambridge University Press, Cambridge, U.K., and New York, N.Y., U.S.A.. This version: IPCC website. Archived from the original on 29 October 2010. Retrieved 18 March 2010.