As the world heads for negotiations over a global climate deal next month, an influential forecasting agency said Tuesday that current energy policies were not sustainable, and that a vast transformation of energy use was required to fend off the worst consequences of global warming. In the absence of a global deal to limit the emissions of carbon dioxide, energy consumption will soar over the next decades. This would result in a catastrophic rise in global temperatures, according to the International Energy Agency, an adviser to industrialized nations that is based in Paris. 'Continuing on today's energy path, without any change in government policy, would mean rapidly increasing dependence on fossil fuels, with alarming consequences for climate change and energy security,' the agency said. Government officials from about 190 nations will meet next month in Copenhagen to try to hammer out an international deal to replace the agreement known as the Kyoto protocol, which expires in 2012. But international negotiators have signaled that an agreement is unlikely to be reached this year in the absence of a broad consensus on how to share the costs of switching to lower-carbon technologies and fuels. The recession, the energy agency said, offers an opportunity to make big strides in lowering emissions. As a result of reduced economic activity this year, global emissions are expected to fall as much as 3 percent, the steepest decline in 40 years. Without a new global agreement, carbon emissions will rise by 40 percent by 2030, the agency said. More than half of that growth will come from China alone, with the rest coming from other developing nations. The agency's forecasts are based on the assumption of no changes in energy policy from governments. Global electricity demand, for example, would rise by 76 percent by 2030, requiring the addition of five times as much production capacity as exists today in the United States. Forecasters now expect global oil consumption to grow 1 percent a year in the next two decades, reaching 105 million barrels a day by 2030, from 85 million barrels a day in 2008. That estimate is lower than last year's forecast for 2030 of 106 million barrels a day. 