The United Nations stated that investing in energy efficiency for power plants, buildings, and cars is the most effective way to combat global warming, despite the high cost of hundreds of billions of dollars. According to a UN report presented at a meeting in Vienna with delegates from 158 nations, developing countries can reduce greenhouse gas emissions more affordably than wealthy nations. The report also highlighted that the necessary funds to stabilize emissions by 2030 would represent a small percentage of projected GDP or global investment flows. Yvo de Boer, the head of the U.N. Climate Change Secretariat, emphasized the importance of energy efficiency in reducing greenhouse gases in the short term. The 216-page report was recently released online and could provide guidance for governments meeting in Austria to address long-term strategies for combating global warming beyond the UN's Kyoto Protocol. The protocol requires 35 wealthy nations to limit greenhouse gas emissions by 2008-2012. The report suggests that around $200 billion to $210 billion in additional investments and financial flows will be needed by 2030 to reduce greenhouse gas emissions to current levels. This includes actions related to energy supply, forestry, and transportation. Improving energy efficiency in power plants and implementing measures like enhancing fuel efficiency in vehicles or increasing insulation in buildings could help achieve this goal. The study predicts a transition to renewable energy sources like solar and hydropower, as well as some nuclear power. It also projects that investments in helping countries adapt to the effects of climate change will amount to tens of billions of dollars in 2030, including measures like increased disease treatment and beach protection. The report suggests that carbon markets must be expanded to meet the demand for more investments and financial support. Currently, companies are accountable for approximately 60 percent of worldwide investments. Experts noted that this report is the first of its kind to outline the necessary investments for a single year, specifically 2030. The report addresses some of the gaps in the overall understanding of climate change provided by previous reports, such as one by former World Bank chief economist Nicholas Stern who argued that it would be more cost-effective to address climate change now rather than waiting to deal with its consequences. U.N. reports this year have also predicted that global warming will result in more heat waves, droughts, disease, disruptions to agriculture, and rising sea levels. De Boer emphasized the need for increased investments in developing nations, stating that the majority of cost-effective opportunities lie in these countries. He also noted that this does not mean that wealthy nations should only focus on investing abroad rather than domestically, as more than half of the required energy investments are needed in developing countries. China is increasing its coal-fired power plants by two every week to support its expanding economy. The speaker suggested that investing in cleaner technology, like removing carbon emissions and storing them underground, would be beneficial.