A free good is a good that we can consume in infinite quantities without foregoing any resources. These would include those things freely given by nature such as sunlight, as we use the nutrients of sunbeams. An economic good is a good that has an opportunity cost to be produced. This includes all goods that are not free.
             Because of things like the Kyoto Accord, air or that is to say clean air as well as global temperature are becoming economic goods. This stays true to the theory of economics: you cannot get something for nothing. Since the Kyoto Accord demands that all countries reduce all greenhouse gas emissions of 1990 by 5.2% by 2012 or to exist within a maximum output limit of greenhouse gases per capita, clean air becomes a good which must be invested in to maintain. This requires the use of the factors of production to limit or reduce a country's output of greenhouse gases.
             The factors of production are the resources that are needed for production. These include land (all natural resources), labour (all human resources), capital (machinery and equipment) and enterprise (risk taking to make profits). If a restaurant is growing into a chain with multiple locations, land is needed to build these locations and resources are needed for building and providing food to the consumer. Labour is needed to plan the expansion, build the new locations and operate these new locations. Capital is utilized in the form of construction machinery and the equipment used in the restaurant's kitchen. This is all made possible because of the entrepreneur backing the expansion for a net profit.
             The Kyoto protocol will simply decrease the need for factors of production put into things that produce greenhouse gases and more will be needed for things that maintain or reduce a country's output of greenhouse gases. The demand for fossil fuels will drop, as alternative energy sources are used more and invested in by government and p...