*4.1. Nationwide SDA of China*

We estimated the total primary fossil energy consumptions in China by using Equation (3). The total primary fossil energy consumed in China increased by 61%, from 2682 million tonnes of standard coal equivalent (Mtce) in 2007, to 4319 Mtce in 2012. In particular, coal consumption made up the most substantial fraction, growing from 2162 Mtce to 3399 Mtce (Figure 1). It is important to determine what the sources were of the remarkable increase in the fossil energy consumptions during the recent five years, between 2007 and 2012.

From the SDA results, we found that final demand shifts were the dominating sources that pushed each energy-use upward, by 2259 Mtce in total (84% of the energy consumption in 2007) (Figure 2). It is also important to identify the role of technology changes in primary energy use. Looking at the technology effect, which is a combined effect of the energy input level, energy composition, and non-energy input effects in Figure 2, technological changes have contributed to decreasing fossil energy use by 684 Mtce in total. Thus, expanding consumptions lead to economic growth and fossil energy growth in China, while the Chinese governmen<sup>t</sup> can expect that technological changes can help to partially offset fossil energy growth.

**Figure 1.** Total primary fossil energy consumed in China in 2007 and 2012.

Using the SDA technique developed in this study, we can further decompose the technology effect into the following three effects: energy input level, energy composition, and non-energy input effects. Looking at these three effects in detail, using Figure 2, between 2007 and 2012, the energy input level effect was the main driver offsetting the increase of all fossil energy types, helping to reduce the energy consumption by 1205 Mtce (45% of the energy consumption in 2007). On the other hand, the energy composition effect was a driver of increasing the consumptions of coal and natural gas by 198 and 12 Mtce, respectively, while reducing oil consumption by 79 Mtce, leading to a 131 Mtce energy growth overall (Figure 2). The non-energy input effect was a driver of increasing the fossil energy consumption by 389 Mtce (15% of energy consumption in 2007) (Figure 2). Thus, the energy saving effect through technological changes was weakened by both energy composition and non-energy input effects; therefore, the Chinese governmen<sup>t</sup> should put effort into maximizing the technology-induced energy saving effect through an improvement in energy mix and non-energy input.

**Figure 2.** Nationwide structural decomposition analysis (SDA) for each fossil-energy type in China.

### *4.2. Decomposition of Technology Effects by Province and Sector*
