Cap and Share – A fair way to cut greenhouse emissions

Drastic cuts in the world’s greenhouse gas emissions are required to avoid a climate catastrophe. A worldwide agreement to secure such cuts will be impossible to negotiate unless both the pain and the benefits are shared equitably around the world. Moreover, the sharing system must be robust enough to ensure that the cuts agreed actually happen. Cap & Share is both robust and equitable. It has the additional advantage that, until it is adopted globally, it can be used by individual countries to make sure their emissions take a downward path. This 32 page Feasta booklet explains how C&S could be used to halt climate change at a global level.

Hardcopies are available for €5, postpaid. Paid-up Feasta members will be posted a copy free if they email a request.

Executive Summary and Overview below, or download the entire booklet


Cap and Share was developed to meet the twin challenges presented by climate change and the peak in the world supply of easily-extracted oil. It is a variant of cap and trade and would limit the use of coal, gas and oil. It can, however, be used to share the benefits from using any scarce natural resource. It works by placing a cap on the use of the scarce resource and charging the users whatever price is necessary to balance their demand with the capped supply. The receipts from the resource users are then shared on an equitable basis amongst all those with an interest in the resource involved.

This paper deals with the use of C&S to deal with oil peak and climate change. If it were to play that role globally, C&S would cap world fossil fuel greenhouse emissions and then tighten the cap year by year at a faster rate than oil production was decreasing. This would make the emissions tonnage set by the cap a scarcer resource than the oil supply. As a result, the whole of the extra amount that users would have been forced to pay the producers for supplies of the scarce oil would be captured in the price paid for C&S emissions permits.

The captured money would then be shared amongst those with a claim on the capped scarce resource and, since that resource is the limited capacity of the sky to act as an emissions dump, everyone on Earth would have an equal claim and thus get an equal share. The emissions permits would also be scarcer than the supply of coal and gas, so C&S would capture the extra that people were prepared to pay to use them too.. This extra is what economists call the “scarcity rent”. After some deductions which are explained in this paper, C&S would then share the total rent from the three fossil fuels amongst everyone on the planet.

The first paragraph mentioned charging resource users for their use of a scarce resource. Under Cap and Share, these charges are collected indirectly. The emissions permits are not sold to fossil fuel users – that would be difficult because there are billions of these. Instead, they are sold “upstream” to companies introducing fossil fuels to the global economy. As only a small number of firms produce most of the fossil fuel used in the world, this makes C&S easy to administer. Each producer is required to acquire enough permits to cover the eventual emissions from the fossil fuels they extract.

Of course, the fuel firms have to add the cost of the permits to their prices and this puts up the cost of everything sold because all goods and services have an energy content. However, anyone who uses, directly or indirectly, rather less energy than is produced from the fuel burned when their share of each year’s capped emissions is released is likely to receive more money from selling their permits than their cost of living goes up. As a majority of people in the world manage on less than the average amount of energy used per person, most people would gain financially from the use of C&S. This would make C&S popular and therefore politically robust.

The paper argues that C&S needs to be adopted urgently not just for climate reasons but because the scarcity rent being captured by fossil fuel producers is concentrating global wealth in a way that threatens to collapse the world economy. The payment of scarcity rent is already causing severe hardship for millions of poorer people around the world.

The paper describes the way C&S could be used as the operating system for the fossil fuel part of a global climate agreement. Other systems are going to be needed to enhance greenhouse gas sinks and conserve the stocks of carbon held in soils and plants. The various options that could be incorporated into the design of C&S are described and the paper looks at the changes that would be required in other systems, such as the money-creation system, for C&S to work well. The paper ends with an account of the steps being taken to get C&S adopted internationally, and stresses that before this can happen, the concept needs to gain massive public support.


Cap and Share seeks to provide a simple, workable and ethical economic framework for dealing with the climate crisis. It is based on the belief that every human being has a right to an equal share of the fees that fossil fuel users would be prepared to pay for the right to discharge greenhouse gases into the global atmosphere.

Under C&S, global emissions would be capped at their current level and then brought down rapidly year by year. Each year, the tonnage of emissions that the world community decided that it could risk releasing over the following twelve months would be shared equally amongst the Earth’s entire adult population. Each of us would actually receive a “fossil fuel pollution authorisation permit” (PAP) conveying the right to our individual share of that year’s global emissions and making us responsible for it.

The important thing to note about these permits is that they would not ration our personal energy use. Instead, they would permit fossil fuel production. They would be valid for a year, during which people would sell them to financial intermediaries such as banks and post offices, who, in turn, would sell them on to oil, coal and gas producers. These producers would need to acquire enough permits to cover the carbon dioxide emissions from every tonne of fossil fuel they sold and international inspectors would check to ensure they did.

Cap and Share is clearly equitable and, arguably, fairer than any other practical method of sharing out rights to emit around the world. It would also be robust because, as the tonnage of emissions being distributed was reduced year by year, the market value of each person’s permit allocation would increase, ensuring that poorer people received an income from the sale of their permits which enabled them to buy food and fuel as these became increasingly expensive. Since the reductions required in fossil fuel use to avert a climate catastrophe are so rapid and deep, adopting some other greenhouse gas control system that failed to protect the poor would cause serious injustice and provoke massive opposition. C&S provides an orderly way of managing the transition from fossil fuels to alternative energy sources with the market setting the price at which the right to emit is sold.

Note: Feasta is a forum for exchanging ideas. By posting on its site Feasta agrees that the ideas expressed by authors are worthy of consideration. However, there is no one ‘Feasta line’. The views of the article do not necessarily represent the views of all Feasta members.