1. Introduction
Sustaining economic growth while reducing dependence on fossil fuels remains a challenge in our era of climate change. In addition to the need for reducing emissions, continuingly increasing fossil fuel prices, fears of unaffordable and rapidly depleting sources of fossil fuels, and the desire to transitioning into a low carbon economy have combined to heighten the importance of renewable energy use [
1]. Several countries have set a target of specific renewable energy share in their total energy consumption. For example, Germany aims to supply electricity solely from renewable energy sources by 2045. China also pledges to be carbon neutral by 2060 and sets the share of non-fossil fuels in primary energy consumption to around 25% by 2030 from a previous commitment of 20%. However, increasing renewable energy consumption is not easy for many developing countries, especially for rapidly growing economies as their demand for energy is increasing and their technical and financial capacities for a large-scale supply of renewable energy are limited. In this regard, looking for possible ways to increase renewable energy consumption while maintaining economic growth is required.
Industrialization generally results in a structural transformation from fossil fuel-based and low technology to clean energy-based and medium- and high technology. Medium- and high-tech industries are the value-added manufacturing sectors with higher technological intensity and productivity. They are referred to the level of technology that companies and industries producing goods with innovative qualifications and advanced technologies [
2,
3]. High technology industries include, for example, aviation and spacecraft industry, pharmaceutical industry, accounting and information processing technologies, radio, television and communication equipment industry, and medical and optical devices industry [
4]. Thus, the production and export of medium- and high-tech products are an important source of export-oriented growth and development, and of the transition to a low-carbon economy [
5,
6,
7].
There have been several studies on socio-economic factors affecting renewable energy consumption [
8,
9,
10,
11,
12,
13,
14,
15]. However, new drivers such as medium- and high-tech export have been given much less attention, especially in the context of developing countries [
16]. In addition, existing research mainly explores the competitiveness benefit of the policies on renewable energy use in conventional industrial sectors, such as in iron, steel, paper, and glass industries [
17]. Globalization has facilitated trade among countries, and the export of medium- and high-tech products have been promoted in rapidly growing economies. However, so far, the causal effects of trade in general, on renewable energy use in both short- and long- terms are weak and scattered [
16,
18,
19], and the effect of medium- and high-tech export on renewable energy use has not been investigated, especially in the context of rapidly growing economies. This is the main motivation for our study.
Theoretically, high- and medium-tech export affect renewable energy use through three channels. First, higher export of high- and medium-tech goods stimulate domestic production of these exported goods and hence economic growth. Increases in domestic production of these goods and economic growth change the energy demand as energy is a key input for production. This is referred to as the scale effect. Second, trade openness allows countries to exchange energy-saving and cleaner energy technologies, which are exported by developed economies and imported by developing economies [
20,
21,
22,
23]. Such exchange facilitates technological advancement. This is referred to as the technique effect. Third, economic growth leads to economic structural transformation which means that at the beginning of the transformation when the economy is largely agricultural-based, energy intensity is low. However, at a later stage when industrialization starts, energy intensity increases. At the same time, economic growth makes people better-off and increases their awareness of the environment, thus demand more medium and high-tech goods from environmentally friendly producers. This is referred to as the composite effect. The net effect depends on the stage of economic growth and the changes in consumption patterns of consumers. While developed economies have advantages in improving technologies for promoting renewable energy, developing countries are less able to do so and most of them may rely on technology transfers from developed countries, but for various reasons, technology transfers might be constrained. Therefore, at an earlier stage medium- and high-export from developing countries may still demand more fossil-based resources. Later on, renewable energy use will increase.
We focus our analysis on the nine countries of the Association of Southeast Asian Nations (ASEAN), including Cambodia, Indonesia, Laos, Malaysia, Myanmar, the Philippines, Singapore, Thailand, and Vietnam (hereafter referred to as ASEAN-9 countries). The ASEAN has 10 member countries but we purposely exclude Brunei as its energy consumption solely depends on fossil fuels. Even though these countries differ in several aspects, especially in terms of income per capita (
Figure 1), they are commonly known as rapidly growing economies and thus have an increased energy demand. It is projected that the overall primary energy supply will increase from 621 Mtoe in 2015 to 1.544 Mtoe in 2050, an annual increase of 2.6%; and the gross final energy consumption will increase with an annual rate of 2.4%, from 436 Mtoe in 2015 to 1006 Mtoe in 2050. However, ASEAN remains highly reliant on fossil fuels. Nearly 80% of the global primary energy supply by 2050 are projected to adhere to fossil fuels. The heavy reliance on fossil fuels along with the decreasing domestic fossil fuel stocks would force the ASEAN’s member states to import more fossil fuels. ASEAN is currently the 3rd largest economy in the Indo-Pacific and the 5th largest economy in the world. It has a combined gross domestic product (GDP) of
$US 2.8 trillion, and is also the 3rd fastest-growing major Indo-Pacific economy in the past decade, after China and India (
Figure 2). As a critical hub for global trade, over
$3.4 trillion in global trade transits through the ASEAN region each year [
24]. Their export of medium- and high-tech has also been growing. However, the share of renewable energy in the total energy consumption of these countries is still modest. In this regard, examining the effect of medium- and high-tech export on renewable energy in ASEAN is of particular interest and relevant for policymakers and the public. We use a 22-year panel dataset (1994–2015) of these ASEAN-9 countries provided by the World Bank World Development Indicators to empirically examine the impact of medium- and high-tech export on the share of renewable energy use in total energy consumption of these countries. These countries are diverse in many aspects. For example, Singapore is an advanced economy, Indonesia and Thailand are upper-middle-income countries, Vietnam is a lower-middle-income country, and Cambodia and Laos belong to the group of the least developed countries. Following the arguments in the previous paragraph, we hypothesize that the relationship between medium- and high-tech export and renewable energy consumption in these ASEAN-9 countries is U-shaped.
2. Literature Review
As natural resources in general and fossil fuels in particular, have been depleting, renewable energy use and economic growth are highlighted as major concerns for sustainable development of the global economy [
25,
26,
27,
28,
29], given the fact that the sustainability of the economic system is dependent on the environment and natural resources [
30]. Due to an increasing level of globalization, global energy demand has changed over time and has been driven by trade-related factors. Trade openness, export-oriented policies, and internationalization are considered crucial in the long-term development strategy of many developing countries [
31,
32]. In this context, recent literature has considered new determinants of energy demand and energy intensity such as export or import product portfolio [
33,
34], trade openness, and technological advancement [
35,
36,
37,
38]. In general, there is a controversy on the effect of trade on energy intensity. On the one hand, many studies find that trade openness positively affects energy intensity [
39,
40,
41,
42,
43,
44,
45]. On the other hand, the effect can be adverse [
46], or ambiguous [
47] depending on competitiveness, factor price, and technology and infrastructure factors ([
35,
48]). Regarding the spectrum of trade and innovation, Samargandi [
35] reveals that trade openness and innovation are significant factors for reducing energy intensity. Beser and Soyyigit [
2] indicate that high-tech export has a strong impact on CO
2 emission in developed economies.
The importance of technology in determining energy use and energy efficiency in developing countries is increasing due to a growing level of internationalization and integration [
22,
49,
50]. Technology innovation induced by investment in research and development and by foreign direct investment is supposed to increase energy use efficiency [
40]. Domestic innovation is also an important contributor to technical development [
49,
51]. To mitigate the negative effects of climate change, technological progress is crucial [
52], and increased R&D is associated with more technical innovation and renewable energy adoption [
53] in both developed and developing countries, where renewable energy sources such as biomass, solar, wind and hydropower are adopted [
54,
55]. Recent studies on the relationship between technological advancement and carbon emission demonstrate positive effects of technology innovations on carbon emission reduction [
56,
57,
58]). Liu, Xia, Tao, and Chen [
56], for instance, analyze carbon emission in China and find that increasing technological expenditure could in turn increases carbon emission efficiency. Wang, Zhao, Wang, Guo, Kan, and Yuan [
57] discover that investments in technology decrease carbon emissions. Zeng, Lu, Liu, Zhou, and Hu [
58] find that foreign trade, foreign capital, and technological progress have positive effects on carbon emission reduction.
Several studies examine the drivers of renewable energy use. Most of these indicate the causal interactions between economic growth and renewable energy use [
59,
60,
61,
62], between renewable energy use and sustainable development [
63,
64,
65], between energy use and trade openness, and between technological progress and renewable energy use. For example, Apergis and Payne [
61] investigate the relationship between economic growth and renewable energy use of 20 OECD countries during 1985–2005 and find a bidirectional link between economic outcome and energy use. Fang and Chang [
62] analyze the causality between energy use and economic performance in 16 countries of the Asia Pacific and finds a long-run cointegrating relationship. Kahia et al. [
66] examine the relationship between energy use and economic growth, using a sample of 7 MENA Net Oil Importing Countries (NOICs) during 1980–2012; and their empirical results confirm the bidirectional causality between renewable energy use (and non-renewable energy use) and economic growth. Le and Sarkodie [
67] investigate the nexus between renewable and conventional energy and economic growth, using panel data of 45 Emerging Market and Developing Economies (EMDEs) from 1990 to 2014. They find that renewable energy and GDP growth impact each other. Marques and Fuinhas [
68], using a sample of 24 European countries during 1990–2006, find that the current level of renewable energy use is positively dependent on the previous level of renewable energy use. However, income and prices of fossil-based fuels are not significant for the development of renewable energy during the studied period. Ahmed et al. [
69] investigate the interactions between renewable and non-renewable energies, CO
2 intensity, and economic growth in Myanmar during 1990–2016; and their results reveal that renewable energy use significantly promotes economic growth.
Few studies have also examined the relationship between trade openness, technological innovation, and (renewable) energy use (Alam and Murad [
16], Sohag, Begum, Abdullah, and Jaafar [
22], Sbia et al. [
70,
71], Khan et al. [
72], Cole [
47], Shahbaz, Nasreen, Ling, and Sbia [
21]). Alam and Murad [
16] reveal that economic growth, trade openness, and technological progress significantly influence renewable energy use in 25 OECD countries. Sohag, Begum, Abdullah, and Jaafar [
22] employ a dataset during 1985–2012 in Malaysia and find that while economic growth and trade openness are the main determinants of energy use, technological innovation reduces energy use in manufacturing sectors. Sbia, Shahbaz, and Hamdi [
70] examine the impacts of foreign direct investment, trade openness, clean energy price, carbon emissions, and economic growth on the demand for energy in the United Arab Emirates. Their findings indicate that trade openness and foreign direct investment reduce energy use because energy-efficient technologies have been employed. By comparing upper-middle-income countries in Asia, Europe, Africa, and America, Khan, Yaseen, and Ali [
72] indicate that trade can induce technology transfer for renewable energy. Shahbaz, Nasreen, Ling, and Sbia [
21] use the data from 91 high, middle, and low-income economies and conclude that domestic energy use is affected by trade openness through several channels such as technological transfers, economies of scale, and input factors. In high-income economies, an inverted U-shaped relationship between trade openness and energy consumption is found. According to Shahbaz, Nasreen, Ling, and Sbia [
21], the U-shaped relationship between trade openness and energy consumption exists when low and middle-income countries import or use energy-efficient technologies from developed countries to lower energy consumption, on the one hand; and on the other hand, when developed countries allow to release those technologies and share profits for low and middle-income countries that have limited access to technology and capital.
A most recent study that is close to our work in terms of geographical coverage (for ASEAN with a 22-year span of time) is Azam, Khan, Zaman, and Ahmad [
25], who find that trade openness has a positive relationship with energy consumption in Thailand, Malaysia, and Indonesia. Apart from trade openness, they discover that population growth increases the energy consumption in Malaysia, while it decreases energy consumption in Indonesia. Real GDP is found to have a positive relationship with energy consumption in Thailand, Malaysia, and Indonesia.
The causal effects between international trade (exports or imports) and renewable energy use in both short- and long- terms that have been found so far are weak [
16]. The results from Sadorsky [
20] for a sample of Middle Eastern countries show that international trade increases domestic use of energy. In addition, Shahbaz, Nasreen, Ling, and Sbia [
21] conclude that a U-shaped relationship exists for high-income countries, whereas an inverted U-shaped relationship is found for middle- and low-income countries for the relationship between international trade and energy use.
In sum, none of the previous studies examine the impact of medium-and high-tech export on renewable energy use. Our study is thus aimed to contribute to filling this gap. The contribution of our study to the literature are two-fold. First, our study is the first effort to examine the effects of medium- and high-tech export on renewable energy share in total energy consumption for this group of rapidly expanding economies. To our best knowledge, only Shahbaz, Nasreen, Ling, and Sbia [
21] discover non-linear relationships between trade openness and energy consumption for two country groups, high-income countries and middle- and low-income countries. Second, from a methodological perspective, we use panel data and employ a fixed-effects regression model with the Driscoll–Kraay nonparametric covariance matrix estimator to account for unobservable time-invariant factors and sectoral and temporal dependence. These concerns have not been successfully addressed in many previous studies (Azam et al. [
25]).