What’s A Carbon Tax?

A carbon tax is a tax on the carbon content of fuels -- effectively a tax on the carbon dioxide emissions from burning fossil fuels. Thus, carbon tax is shorthand for carbon dioxide tax or CO2 tax.

Carbon atoms are present in every fossil fuel -- coal, oil and gas. They are the primary source of the heat released in fuel combustion, and essentially all of them are converted to CO2 when the fuel is burned. Carbon dioxide, an otherwise non-lethal and innocuous gas, rises in the atmosphere and remains resident there, trapping heat re-radiated from Earth’s surface and causing global warming and other harmful climate change. In contrast, non-combustion energy sources -- wind, sunlight, falling water, atomic fission -- do not convert carbon to carbon dioxide. Accordingly, a carbon tax (or CO2 tax) is effectively a tax on the use of fossil fuels, and only fossil fuels.

The carbon content of every form of fossil fuel, from anthracite to lignite coal, from residual oil to natural gas, is precisely known. So is the amount of CO2 released into the atmosphere when the fuel is burned. A carbon tax thus presents few if any problems of documentation or measurement. As discussed on the Carbon Tax Center's Implementation page, administering a carbon tax should be simple; utilizing existing tax collection mechanisms, the tax would be paid far “upstream” (e.g., at the point where fuels are extracted from the Earth and put into the stream of commerce, or imported into the U.S.). Fuel suppliers and processors would pass along the cost of the tax to the extent that market conditions allow.

Per unit of energy (or Btu), natural gas emits the least CO2 of any fossil fuel when burned, and coal the most, with petroleum (oil) products such as gasoline occupying the middle range. Generally, a Btu from coal produces 30% more carbon dioxide than a Btu from oil, and 80% more than from natural gas. A carbon tax would follow these proportions, taxing coal somewhat more heavily than petroleum products, and much more than natural gas.

To the extent carbon is included in a product such as plastic, but is not burned, that carbon will not be taxed. Similarly, to the extent the carbon used to produce energy is permanently sequestered rather than released into the atmosphere, that carbon will not be taxed or a tax credit will be provided.

Very little taxation of carbon is presently in place in the world (see this description at the Carbon Tax Center). Nevertheless, a large and growing number of economists, policy-makers and concerned citizens regard stiff carbon taxes as essential for combating the climate crisis that gravely threatens humankind and other living things.

Why A Carbon Tax?

The rationale for a carbon tax is simple: the levels of CO2 already in the Earth’s atmosphere and being added daily are destabilizing established climate patterns and threatening the ecosystems on which we and other living beings depend. Very large and rapid reductions in the United States’ and other nations’ carbon emissions are essential to reverse runaway climate change and avert resulting severe weather events, inundation of coastal areas, spread of diseases, failure of agriculture and water supply, infrastructure destruction, forced migrations, political upheavals and international conflict.

A carbon tax must be the central mechanism for reducing carbon emissions. Currently, the prices of gasoline, electricity and fuels in general include none of the costs associated with devastating climate change. This omission suppresses incentives to develop and deploy carbon-reducing measures such as energy efficiency (e.g., high-mileage cars and high-efficiency heaters and air conditioners), renewable energy (e.g., wind turbines, solar panels), low-carbon fuels (e.g., biofuels from high-cellulose plants), and conservation-based behavior such as bicycling, recycling and overall mindfulness toward energy consumption. Conversely, taxing fuels according to their carbon content will infuse these incentives at every chain of decision and action -- from individuals’ choices and uses of vehicles, appliances, and housing, to businesses’ choices of new product design, capital investment and facilities location, and governments’ choices in regulatory policy, land use and taxation.

A carbon tax won’t stop global climate change by itself -- other, synergistic actions are required as well. But without a carbon tax, even the most aggressive regulatory regime (e.g., high-mileage cars) and “enlightened” subsidies (e.g., tax credits for efficiency and renewables) will fall woefully short of the necessary reductions in carbon burning and emissions.

No Tax Increase? How?

A carbon tax should be revenue-neutral. At least that’s what we (Carbon Tax Center) and many other carbon tax proponents are advocating. Revenue-neutral means that little if any of the tax revenues raised by taxing carbon emissions would be retained by government. The vast majority of the revenues would be returned to the American people, with some small amount utilized to mitigate the otherwise negative impacts of carbon taxes on low-income energy users.

Two primary return approaches are being discussed. One would rebate the revenues directly through regular (e.g., monthly) equal dividends to all U.S. residents. In effect, every resident would receive equal, identical slices of the total revenue pie. Just such a program has operated in Alaska for three decades, providing residents with annual dividends from the state’s North Slope oil revenues.

In the other method, each dollar of carbon tax revenue would trigger a dollar’s worth of reduction in existing taxes such as the federal payroll tax or state sales taxes. As carbon-tax revenues are phased in (with the tax rates rising gradually but steadily, to allow a smooth transition), existing taxes will be phased out and, in some cases, eliminated. This “tax-shift” approach, while less direct than the dividend method, would also ensure that the carbon tax is revenue-neutral.

Note that each individual’s receipt of dividends or tax-shifts would be independent of the taxes he or she pays. That is, no person’s benefits would be tied to his or her energy consumption and carbon tax “bill.” This separation of benefits from payments preserves the incentives created by a carbon tax to reduce use of fossil fuels and emit less CO2 into the atmosphere. Of course, it would be extraordinarily cumbersome to calculate an individual’s full carbon tax bill since to some extent the carbon tax would be passed through as part of the costs of various goods and services.

Softening The Impact

A carbon tax, like any flat tax, is regressive -- by itself. However, the regressivity of a carbon tax can be minimized, and perhaps eliminated altogether, by keeping the tax revenue-neutral in a way that protects the less affluent.

The operative fact is that wealthier households use more energy. They generally drive and fly more, have bigger (and sometimes multiple) houses, and buy more stuff that requires energy to manufacture and use. As a result, most carbon tax revenues will come from families of above-average means, along with corporations and government.

That is why the two “return” approaches discussed above -- carbon dividends or tax-shifting -- can turn the carbon tax into a progressive tax. Because income and energy consumption are strongly correlated, most poor households will get more back in carbon dividends than they will pay in the carbon tax. The overall effect of a carbon tax-shift could be equitable and perhaps even “progressive” (benefiting lower-earning households).

Cap-and-Trade Problems

A tax on carbon emissions isn’t the only way to “put a price on carbon” and thereby provide incentives to reduce use of high-carbon fuels. A carbon cap-and-trade system is an alternative approach supported by some prominent politicians, corporations and mainstream environmental groups.

CTC has no ideological animus against cap-and-trade systems. In fact, the U.S. sulfur dioxide cap-and-trade system instituted in the early 1990s deserves some of the credit for efficiently reducing acid rain emissions from power plants. However, the scale of a carbon trading system -- it would be up to 100 times larger than that for sulfur -- combined with the lack of readily available “technical fixes” for filtering or capturing CO2, appear to rule out the sulfur cap-and-trade system as a model for carbon.

We regard a carbon tax as superior to a carbon cap-and-trade system, for five fundamental reasons:

• Carbon taxes will lend predictability to energy prices, whereas cap-and-trade systems will do little to mitigate the price volatility that historically has discouraged investments in less carbon-intensive electricity generation, carbon-reducing energy efficiency and carbon-replacing renewable energy.
• Carbon taxes can be implemented much sooner than complex cap-and-trade systems. Because of the urgency of the climate crisis, we do not have the luxury of waiting while the myriad details of a cap-and-trade system are resolved through lengthy negotiations.
• Carbon taxes are transparent and easily understandable, making them more likely to elicit the necessary public support than an opaque and difficult to understand cap-and-trade system.
• Carbon taxes can be implemented with far less opportunity for manipulation by special interests, while a cap-and-trade system’s complexity opens it to exploitation by special interests and perverse incentives that can undermine public confidence and undercut its effectiveness.
• Carbon tax revenues can be rebated to the public through dividends or tax-shifting, while the costs of cap-and-trade systems are likely to become a hidden tax as dollars flow to market participants, lawyers and consultants.

See the Carbon Tax Center's Tax vs. Cap-and-Trade page for more.

What About China?

The imminence of China’s leap-frogging the U.S. as the World’s #1 annual carbon emitter -- it may happen as early as this year or next -- is being cited to defend American inaction on carbon reductions. This stance ignores several central points.

For one thing, the U.S. will continue to be the world’s biggest contributor to global climate change long after China, or even India, surpasses us in annual emissions. That’s because carbon dioxide molecules, once emitted, remain “resident” in the atmosphere for approximately a century. Considering the many decades in which America’s carbon emissions dwarfed everyone else's, of the CO2 now warming Earth, more than three times as much is the product of American emissions as Chinese emissions. Based on present trends, the earliest that China will surpass the United States as the leading source of CO2 is mid-century, i.e., around 2050. (See Slideshow, slide #8.)

Second, the United States will continue to dump the most CO2 into the atmosphere on a per capita basis for years to come. The average American is responsible for creating as much CO2 in a day as do people in developing countries in an entire workweek.

Third, just as corporations here use China’s inaction on carbon to justify U.S. inaction, so too are industry and government in China using our temporizing on carbon to rationalize theirs. The way out of this “alliance of denial,” as The New York Times terms it, is to stop delaying and start acting. Breaking this cycle should be easier for the United States, insofar as our per capita use of energy (and emissions of carbon) is many times greater than China’s, and given our well-developed political and administrative institutions.

Last, while it is true that only concerted action by all the world’s nations and peoples can meet the climate crisis head-on, it is equally true that every action that reduces carbon emissions helps protect and stabilize climate. The injunction that the perfect must not become the enemy of the good has never been so apt as it is here and now, in Earth’s climate emergency.

This solution is an extended excerpt of an article on the Carbon Tax Center's website.