Developing countries may receive assistance in constructing nuclear power plants as part of a plan discussed at a climate conference in Bonn involving 170 nations. This plan aims to expand a UN program that helps reduce greenhouse gas emissions by allowing wealthy countries to invest in renewable energy projects abroad and receive credit for reducing emissions domestically. Yvo de Boer, the head of the UN Climate Change Secretariat, stated that the inclusion of nuclear power in the program is a topic that needs to be examined further. Other suggestions at the conference include providing credits for carbon capture and storage, promoting reforestation efforts to absorb carbon dioxide, and supporting renewable energy projects. Numerous countries and environmental activists are against the idea of including nuclear power in the Clean Development Mechanism (CDM), which is a component of the United Nations' Kyoto Protocol aimed at reducing greenhouse gas emissions by 2012. Martin Hiller from the WWF conservation group believes that nuclear power is not a sustainable energy source and should not be eligible for the CDM, which he argues should focus on promoting renewable energy instead. He stated that nuclear power, despite emitting minimal greenhouse gases compared to coal, oil, and gas, was considered too risky. The talks in Bonn, part of negotiations for a new U.N. climate treaty to replace the Kyoto Protocol, will not include decisions on revamping the CDM. Many delegations are against including nuclear power in the CDM. There is uncertainty over whether nuclear power should be used as an alternative to fossil fuels to combat rising temperatures and their associated impacts. De Boer estimated that the CDM could provide up to $100 billion annually to developing nations if industrialized countries committed to significant emissions reductions and half of those reductions were made abroad. That was also assuming that credits for avoiding greenhouse gas emissions would be around $10 per ton. The CDM has projects in progress that could prevent a total of 2.7 billion tonnes of emissions by 2012, which is about the same as the combined annual emissions of Japan, Germany, and Britain. De Boer dismissed criticisms of the CDM, including claims that it benefits carbon traders and companies in China profiting from destroying HFC 23, a potent greenhouse gas produced during refrigerant manufacturing. He argued that finding a way to profit from reducing greenhouse gases is not unethical, as it demonstrates the effectiveness of the market mechanism. Additional criticisms of the plan center around the question of whether the funding has actually resulted in reductions in emissions, or if these reductions would have occurred regardless due to preexisting government support for wind power in countries like China and India.