A low-carbon economy (LCE) is a concept which was first proposed in the UK Energy White Paper 2003, entitled Our energy future: creating a low-carbon economy. Thereafter, LCE became a buzzword arousing increasingly worldwide concern. The Energy White Paper, however, presents no precise definition of LCE, nor the relevant methods or standards for delimitating LCE.

The LCE, thought as a worldwide hot topic, is still a vague concept updating over time. In the mainstream view it refers to an economy having a minimal output of greenhouse gas (GHG) emissions into the biosphere.

When the concept was first put forward, most scientific and public opinion had come to the conclusion that the over-concentration of GHGs in the atmosphere due to anthropogenic causes is the direct cause of the ongoing global warming. Therefore, a campaign to implement LCE globally is believed to be imperative for averting catastrophic climate change.

Nearly all countries have realized the necessity of transition toward LCE and have acted accordingly, which has become an important component of the long-term global warming mitigation strategy. In the meantime, the draining of non-renewable energy resources, increasing energy demand and soaring energy prices are other factors that promote the global low-carbon transition.

The LCE aims at minimizing GHG emissions from all anthropogenic activities, featuring higher efficiency in every process of energy production and consumption. Specifically, as a new economic pattern, LCE has several substantial differences with the traditional economic modes characterized by high energy consumption, poor efficiency and high emission. For example, LCE requires high efficiency in manufacturing energy utilization and a pretty high proportion of renewable energy in energy structure; it encourages more bicycling, walking and use of low carbon-emission and public vehicles instead of private cars in transportation; office buildings and houses should be built with high efficiency and energy-saving material and in an energy conserving manner. In the final analysis, through energy-saving technology innovation, application of low carbon dioxide emission technology and improving energy utilization efficiency, LCE can gradually reduce per capita carbon emissions and establish low carbon living environment and lifestyle.

Though various governments appreciate a low-carbon economy, the focus and concern are different when it comes to the huge gap between developed countries and the developing world. Governments in developed countries could win votes as long as local people's present lifestyle and living conditions can be maintained. However, developing countries face much tougher challenges in improving their overall living standard toward middle-income level. So imposing limitation on GHGs of developing countries is not only unfair to them, but also somewhat wrong morally.

As a revolution in global economic development and human living pattern, LCE deserves corresponding actions from each country and individual. The requirement for developed and developing countries, however, should not be the same, which is also the basis of the principle of "common but differentiated responsibilities".

Theory and practice already confirm that public opinion on the quality and value of the environment is highly related with their income and the payment capacity for emission mitigation heavily depends on income level. Compared with China's per capita income of US$2000 in 2007, the US averaged at US$46,000, which is 23 times that of China's. In China, the average electricity cost per kilowatt-hour is 6.7 cents while it is 9.1 cents in the US, only 1.4 times that of China's. So in the US it would be easier to mobilize the public to support relief from GHG emissions as well as raise money as funds for implementing LCE. So the huge personal income gap also objectively contributes to the common but differentiated responsibilities between developed and developing countries.

Developed countries are more to blame for global warming rather than developing countries. The current per capita emission of developing countries is significantly lower than that of developed countries, irrespective of the latter's mass emissions in history. Besides, in developing countries many emissions are transferred from developed countries. Ranking at the top of the industry chain, developed countries prefer to move the manufacturing with heavy energy consumption, high pollution and emission to developing countries. Therefore, developed countries should take their due responsibilities in GHG mitigation and address the problems they have caused.

Besides reducing their own emissions, a promising LCE of developed countries means they should shoulder more responsibility in helping developing countries in this regard. Without caring about low-carbon economy in developing countries, LCE of developed countries will lead to more GHG emissions.

The author is a professor with Center of China Energy Economics Research, Xiamen University.