Former president Jiang Zemin has issued a paper calling for energy conservation, saying it is the path the mainland should pursue in its development. It is his first public statement since his retirement in 2004. In the dissertation, Mr Jiang urges the government to give energy conservation top priority in its long-term energy development strategy. Since Deng Xiaoping died in 1997, retired leaders have rarely made public comments on state affairs. Official media reports generally say they spend their days enjoying Peking opera or practising calligraphy. But Mr Jiang has apparently been engaged in research. His 16-page dissertation, published by the Journal of Shanghai Jiaotong University, his alma mater and one of the mainland's top institutes for technology and engineering, is an academic paper with complex graphics and data cited from authoritive institutions. Mr Jiang - along with other retired heavyweight politicians such as former parliamentary chief Li Peng and former premier Zhu Rongji - attended the opening of the 17th party congress in October in a rare joint gathering of current and retired leaders. China-watchers say retired leaders still hold significant sway well after giving up their official titles in a political system dominated by personalities and patronage networks. Some also said Mr Jiang had been active behind the scenes in the run-up to the party congress. In a decision before the congress, the Politburo decided that retired top leaders should have a say on important matters. One Beijing-based scholar said: 'Though his article is more like an academic paper, his public statement itself suggests that he is physically fit and still can make a contribution to the country.' Mr Jiang retired from the post of party general secretary in late 2002 and quit his last post, as chairman of the Central Military Commission, in 2004, handing over power to his successor, President Hu Jintao . In the article, entitled 'Reflections on Energy Issues in China', Mr Jiang analyses the global energy situation. The editor of the journal wrote that the paper explored opportunities and challenges to the mainland's development and national security by proposing a new energy development strategy with Chinese characteristics, focusing on energy conservation, high efficiency, diversified development, environmental protection, technological innovation and international co-operation. Mr Jiang said the government should quickly work out a long-term energy strategy that had a bearing on both economic development and national security. He said the mainland should not pursue development by relying on massive consumption of energy, as many western industrialised nations had done, because it had to cope with a more severe shortage of resources. Compared to other parts of the world, the mainland faced severe geological difficulties in tapping its coal, oil, gas and hydropower resources, and it should rely on energy conservation, not imports, to fuel long-term development, Mr Jiang said.