1. Introduction
In the economics of transition from traditional fossil fuel (FF) energy to renewable (RE) energy, multifaceted decoupling has been the chief narrative in the current literature [
1,
2,
3]. The concept of eco-economic decoupling was introduced by the International Resource Panel (IRP) of the UN Environment Programme (UNEP) in 2011, where an estimation is that 140 billion tons of minerals can be used by humans per year by 2050 if decoupling is not achieved [
4]. This definition is tied to goal 12 of the sustainable development goal (SDG) framework of 2015, and is termed “resource decoupling” [
5]. After the introduction of the 2015 Paris Agreement, “impact decoupling” was popularized, which implies that economic output is increased while environmental impacts are reduced in totality [
3,
6]. To actually measure decoupling, the two quasiquantitative terminologies were introduced: (a) Relative decoupling, which is the decline in ecological intensity per unit economic output [
3,
4,
7], and (b) Absolute decoupling, where absolute decline in environmental burden is achieved by reducing emission intensity of the economy [
3]. Thereafter, economists have proposed that the “inverted-U-shaped” environmental Kuznets’ curve (EKC) hypothesis is closely related to relative and absolute decoupling [
3,
8,
9]:
during the initial economic growth period emissions increase at a slower pace with economic output (relative decoupling), while continued economic growth eventually sees emissions decouple from economic output (absolute decoupling) [
10].
While decoupling is closely associated with EKC, several developing countries are in the relative decoupling phase [
3], while developed countries are in absolute decoupling [
3,
11]. This creates a sort of symmetry in decoupling policy-making that is focused on the traditional definition of the EKC. In fact, the EKC hypothesis has also been found to be nonexistent in several cases, mostly in developing economies [
3,
12,
13,
14]. While there is no consensus in the literature, nonlinear economic dynamics and rapid growth of developing countries like India (and, to some extent, although much more developed, China) are the main reasons why EKC has not been validated in the highest carbon emitters [
3,
13,
15]. Decoupling has also suggested that emission intensity and energy intensity reductions are two key strategies that can lead to sustainable energy transition [
3]. However, if nonlinear dynamics of economic growth are not complemented into the decoupling framework, true targets of a net-zero society cannot be met.
The basis of the EKC hypothesis is to determine a point of inflexion on the “inverted-U-shape” of CO
2 emissions with respect to economic growth, which in most previous studies has been assumed to be gross domestic product (GDP) [
3,
9,
16,
17]. However, higher order phenomena are seen in GDP trends, most notably the business cycle, specifically prevalent in high-inflation emerging economies like India [
7,
13]. Business cycles are a result of complex interactions between GDP, interest rates, inflation, employment, and capital [
18]. In some cases, trade cycles are also associated with these higher order phenomena [
19,
20]. Existing literature is mostly based on linear causality assumptions between GDP and macro-CO
2-emissions [
3,
9,
16,
17,
21], which have failed to capture the higher order dynamics that may affect the nature of decoupling frameworks themselves.
Another economic complexity that has been ignored in previous studies is the prevalence of economic shocks. Such shocks potentially reorient the very economic structure of nations and have major ramifications toward the progression of decoupling strategies. For example, the subprime mortgage crisis of 2008 was a global phenomenon, which changed the course of RE development sharply, with Chinese solar panels overtaking Japanese and European production sharply [
22]. At the same time, developing nations’ carbon emissions and emission intensity of electricity use sharply increased post-2008 crisis [
22,
23], implying that there was a lesser incentive to generate clean power than FF power. While many previous studies have revealed how decarbonization patterns changed in the aftermath of the 2008 crisis [
1,
11,
22,
24], the macroeconomic linkages that cause CO
2 emissions to rebound after shocks are not known. In the rebound of COVID-19, we have also seen a rebound in emissions [
25]. This paper builds on the existing frameworks of decoupling and extends them to internalize the stochastic business cycle and economic shock phenomena.
This paper focuses on the energy sector in India, which is currently one of the fastest growing economies and the third-highest global CO
2 emitter [
25,
26]. With the highest global population and the fastest population growth rate among the top five most-populated countries [
27], more than 20% of India is below the globally agreed poverty level [
28]. This means that any innovative RE or energy conservation technology may not percolate to the bottom hierarchy of society [
29], thereby increasing the dependency on FF use. With FF penetration having increased by 250% in the last two decades, RE generation in the energy sector is only 20% compared to FF generation of 75% [
30,
31]. Similarly, the average annual GDP growth rate of 6% for the last 20 years is coupled with an inflation growth of 5.8% in the same period [
32,
33]. However, inflation in India rapidly switches between 4% and 6%, creating significant changes in consumerism, and hence, energy demand [
34]. Accounting for the issue of business cycles’ impact on decarbonization policies, the third-highest global emitter does pose the perfect litmus to test existing pathways and propose novel directions in the aftermath of COVID-19, which is seeing unprecedented inflation levels.
In most existing studies, causality among GDP, CO
2 emissions, and energy use has been analyzed, wherein the direction of causality is usually found to be unidirectional from GDP to CO
2 emissions (or vice versa) or bidirectional [
35,
36,
37,
38]. These specific causality studies are usually limited to specific time periods, wherein a recent study found that these directionalities can change (or even reverse) in different economic regimes [
7]. In more recent macroeconomic studies, capital [
39,
40], TROP [
16,
41,
42], and financial development [
7,
9,
16] have been used as extended proxies for economic growth, with varying causality to CO
2 emissions. However, complex and nonlinear economic dynamics may not carry a simple causality from economic growth to environmental degradation (CO
2 emissions), which is why the envelope of the EKC framework needs to be expanded.
A very interesting issue pops up once we start discussions on causalities among the variables in a 3E nexus. It is hypothesized, from the above modeling assumptions, that in a nonlinear economic system, the causality from GDP to emissions follows a complex pathway that resembles a network. The causality analysis is carried out through vector error correction modeling (VECM), which applies cointegration error correction to a vector autoregressive (VAR) system [
9,
13]. In existing literature, VECM systems are generally considered nonlinear due to the autoregressive properties, without the derivation of the complex pathway between target variables [
9,
43,
44]. However, current studies have not analyzed how much delay a pulse experiences as it traverses the path of causality. The central motivation of this paper is to represent a VECM causal network in the cybernetic circuital model, such that the delay within the causal network can be analyzed. In economic policy analysis, cybernetics have enabled analysis of the memory of macroeconomic systems [
45] and delays in supply chain management [
46]. Using the cybernetic model, a fractional circuit [
45] can enable the visualization of exactly how a macroeconomic 3E system responds to an economic shock. In a brief summary, the major novelties of this paper are:
Introducing a novel EKC/decoupling framework that is capable of internalizing higher order economic phenomena, like business cycles.
Uncovering the pathways of energy–economy–emission (3E) nexus resiliency in the face of exogenous economic shocks: Are shocks really exogenous?
Introducing a novel econometric algorithm to analyze delays among interlinked variables within the 3E nexus frameworks for high-inflation developing economies.
Section 2 of this manuscript introduces a detailed literature review that leads up to this analysis.
Section 3 introduces the methods and data that have been used to construct the empirical study, while
Section 4 sheds light on the key results obtained.
Section 5 is a transformative novel idea that bridges the gap between econometric studies and engineering applications to aid economic policy development for achieving net-zero targets.
Section 6 provides a summary of the findings of this study.
2. Literature Review of Decoupling Frameworks
This section serves both as an introduction to existing EKC analysis frameworks and the knowledge gaps within the frameworks that this study targets. The first strand of EKC literature is limited to causality analysis among GDP, CO
2 emissions, and energy use. The single leading hypothesis development has been used for a majority of the studies, by utilizing auto-regressive dynamic lag (ARDL) Granger causality [
17,
21,
47,
48], which is beneficial for long-run directionality determination. One particular recent study confirmed that both economic growth and energy use significantly degraded the environment in eight developing Asian nations, including India [
49], but the main gap in this study is that the defining characteristics of fast growing emerging economies were not captured. This includes high inflation, energy security issues, and differences between power generation and nonelectricity sectors. As a result, other studies that employed this framework found no evidence of the EKC for other emerging economies [
17,
36,
50,
51].
The second strand extends the EKC envelope to Cobb–Douglas production functions (capital) and international trade (trade openness—TROP). Capital has been internalized as factor productivity [
39,
52,
53,
54] or labor productivity [
39,
51] and served to displace the inflationary growth aspect of developing economies with a more stable indicator. The issue arises with TROP. Although TROP is an important macroeconomic indicator and is not entirely internal to an economy [
55], it is highly stochastic for reliably modeling it into EKC frameworks. Consequently, the outcomes of multiple studies using TROP found increased trade to promote decoupling [
14,
56,
57,
58] but were unable to comment on the energy security dynamics of decoupling.
This has led to multiple studies exploring individual sectors to extract the structure of decoupling with economic phases [
1,
3,
17,
59]. Electricity and carbon market designs have enabled macroeconomic researchers to extract the economic essence of power generation in developing economies through financial and socioeconomic parameters in constructed models [
60,
61,
62]. This led to a recent seminal study on the Indian electricity decoupling status based on economic shock-induced regime change [
7]. The authors of [
7] built production, trade, and electricity trends into the framework and suggested that decoupling in the electricity sector changes from growth to recession phases, and decoupling does not primarily happen with gross domestic product (GDP) but with multifaceted economic indicators like capital and trade openness (TROP). A few other studies also analyzed how the EKC is prevalent in the electricity sectors of developing economies [
25,
63,
64,
65,
66]. However, the main issue is yet to be explored in terms of the entire economic structure, that is, how the complete 3E behaves during economic cycles and shocks.
The final macroeconomic group of studies is neoclassical, where financial development is theorized to influence energy consumption, and thereby, emissions [
65,
67,
68]. While financial development can be a proxy for investment [
16], it is quite difficult to relate social behavior to it. Developing countries, including India, have an extensive middle class and suffer from poverty. From a socioeconomic perspective, social behavior is tied to inflation cycles, market variability, and economic volatility in emerging economies [
25,
69,
70], so much so that the acceptance of decoupling can also be cyclic, a question which has to be addressed in future research. While a particular study focused on omitted variables in system considerations [
71], social behavior was not considered, which can be a major determining factor for EKC’s existence in developing economies like India.
For these purposes, this paper proposes a framework with the following novelties:
While TROP is a very stochastic indicator, it is not directly linked to the higher order behavior of business cycles [
7,
13]. India is a net importer of FF [
7,
72], and therefore, the alternating growths and recessions of business cycles affect energy imports as a control variable over TROP.
Economic shocks are events that can alter the structural orientation of a macroeconomic system. Within this system, RE and FF have different dynamics and even differently affect electricity and nonelectric energy use. For example, after COVID-19, electricity generation in India fell by 6% in the fiscal year 2020–2021 [
73]. Accounting both variables separately within the 3E nexus can accommodate the higher order behavior during periods of crisis.
Inflation is a major cause of nonlinear causality, which has not been analyzed in past literature as to how it affects CO
2 emissions. Moreover, inflation guides social behavior and consumer trends in the business cycle phases [
69,
70]. The consumer price index (CPI) is considered the proxy for inflation within the 3E nexus in this analysis [
7,
69].
Based on these knowledge gaps, this paper attempts to expand the applicability of EKC frameworks even further. On the aspect of resiliency in 3E systems, simply testing the fitting of predictors/indicators does not clarify the cause of the resiliency. Given the fast pace of economic growth in India, it is expected that the service sector has expanded tremendously over the past decade or two. This means GDP to CO2 emissions are not expected to have a direct causal relationship. Moreover, interest rate hikes are a reaction to high inflation, which is where the variables of the 3E nexus are expected to have a delay, which is impossible to analyze in traditional econometric vector models like VAR and VECM. This is why the interlinked variables are assumed to replicate a control system, where a cybernetic breakdown of the model should be capable of showing the delays among interlinked variables within the 3E nexus. As a result, the central hypothesis can be stated as “GDP to macro-CO2 emissions have an indirect causal pathway in a high-inflation economy that is delayed at every stage of the causal relationship”.
5. Discussions: Delays in 3E Feedback Linkages via Cybernetic Analysis
This section dissects the results of the feedback pathways (specifically
Figure 2) to analyze the delay among interlinked variables. In a way, this is a novel direction for VECM analysis, merging econometrics, and engineering applications.
Since short-run impacts are quite stochastic in nature, it has to be of economic interest to act upon long-run feedback pathways and break negative feedback loops to enable energy transition in developing economies. Therefore, the long-run IPES loop is of interest for the delay analysis. While
Figure 2 shows decoupling to be an emergent and complex phenomenon in the Indian 3E nexus under higher order conditions, the propagation of an impulse in the IPES loop is necessary to be analyzed for determining appropriate net-zero policy interventions and the timing of the interventions. In the existing literature, long-run coefficients VECM systems do not reveal the information of delay among interlinked variables (inter alia, system memory), due to which higher order phenomena emerge in the 3E nexus. Recent cybernetic studies have replicated the memory (or delay) of macroeconomic systems [
45] and supply chain systems [
46]. Using cybernetic simulation of the long-run VECM coefficients, the following section introduces an econo-electronic engineering method that can analyze the propagation of an impulse in the long-run linkages, which gives rise to the higher order phenomenon in the 3E nexus modeling.
Following the discussions of [
13,
16,
21,
57,
67,
89,
90,
91], it is evident that there is no consensus on the reasons for causality in complex pathways among economic indicators to C. The authors of [
7] propose that there might be indicator delays that are not captured by the system delay of AIC and BIC [
57,
85,
92], and even ARDL models are single-stage delays [
9,
44,
52], which may not reveal economic realities. The cybernetic circuital elements necessary to simulate an econometric model require time delays and multistaged inputs. For this reason, focus is given on fundamental circuit-building components:
- (a)
Resistance–Capacitance (RC) circuit is known as a delay circuit (Equation (6) and
Figure 4a), where, in principle, we can control the time period of delay by appropriating R and C values.
- (b)
Ideal operational amplifier (Equation (7) and
Figure 4b), where the negative and positive long-run a-VECM coefficients, in principle, are analogized to the inverting (V−) and non-inverting (V+) terminals, respectively.
The transfer function of the R-C circuit is:
where the time constant (T) can be expressed as
.
The transfer function of the OP-AMP is:
where A is the open loop gain for the amplifier.
The IPES loop, with GDP and E-Nel, can be visualized as inputs, while K, CPI and E-Imp can be taken as individual nodes of the loop, represented in Equations (8)–(10). This approach is called segmenting in vector algebra.
The respective coefficients are the ones involved in the vectored expressions of the VECM relations. The above equations can be transformed as follows:
Analogous circuital equations for equations of the above are rewritten in the form of Equations (14)–(16). This is a simple analogy and not a representation of the entire 3E nexus, as the IPES loop itself is not a complete 3E nexus system but an interlinked variable complex. It should be noted that the coefficients are linear combinations of RC elements, while the voltages represent the respective variable.
With respect to the coefficient values in
Table 7, the capacitance values can be chosen to reflect the coefficient values, keeping resistance constant at 17 Ω.
Figure 5 shows the equivalent circuit for Equations (14)–(16). The V
ina and V
inb, representing GDP and E-NEl, respectively, are a train of pulses (duty cycle-26 and frequency-40 Hz). Thus, GDP and E-NEl represent a series of impulses. A low gain amplifier produces a characteristic R–C delay voltage–wave, analogous to economic propagation. A high gain with VCC set at +/−15 V renders amplifier outputs also as pulses, which can reveal the time delay from input to output per the sampling interval (quarterly). This circuit is the impulse response of K, CPI, and E-Imp to impulses of GDP and E-NEl within the higher order echelon.
Table 8 gives a summary of the parameter specifications for
Figure 5.
Figure 6 shows the input voltage at V
ina (for GDP and E-NEl) and the outputs of V
outa (K), V
outb (CPI), and V
outc (E-Imp). The
x-axis divisions are 10 ms apart, interpreted to be analogous to the sampling interval of the 3E nexus model (one quarter). There are quantifiable delays in the feedback between capital, inflation, and energy imports. This cybernetic approach is shown to be quite useful in determining the propagation of macroeconomic impulses in a 3E nexus.
GDP growth is in tandem with inflation, exactly as business cycle movements, and when inflation peaks, capital growth reduces with further inflation. However, the positivity of inflation is far superior to that of equispaced K or GDP, showing that decoupling achievement has to be controlled by reducing inflation (which was already seen to be achievable by building RE capital). The mode of inflation increase is evident from the increased dependency on fossil fuel imports, where import dependency is one prime reason for the Kitchin cycle’s existence in India [
70]. Due to this, we also see that K is increasingly out of phase with GDP. This is also evidence of the result achieved in the VECM coefficients: GDP and CPI are inhibitors of decoupling, while capital is a promoter.
While this delay can be the reason for higher order phenomena in modeled 3E systems, validation of this circuit to reproduce real business cycles is required. CPI is seen to increase with every GDP and E-NEl impulse and slowly approaches a steady state. Once V
outb attains equilibrium, it can indicate the peak of a business cycle (Kitchin), which is now fed to the positive terminal of another amplifier stage in
Figure 7. Since the interest rate is an external determinant, it is assumed to be a constant DC voltage input (as shown in
Figure 7), varying between 1 V and 5 V, and is fed to the negative terminal. This can be analogously thought of as an interest rate movement between 1% and 5%. V
outb′ shows the inflation with the interest rate effect considered.
Figure 8 shows the change in CPI with interest rate considered (V
outb′).
In
Figure 8, as the interest rate increases (increasing voltage), the positivity of inflation is seen to decrease, indicating a reduction in inflation, and upon decreasing interest rate (decreasing voltage), inflation increases. The policy intervention can be made exactly at this point wherein RE innovation, infrastructure, and capital building effectively increase interest rates due to spending, which causes inflation to decrease, which macroeconomically can then decrease FF import dependency, resulting in reduced emissions (whiplash effect). Thus, the circuit model mimics real business cycle movements, evidencing the inverse relationship between interest rates and inflation. This validates the reasons and the linkages within the 3E nexus VECM model that internalizes the higher order behavior in the VECM system.
The results of
Figure 6 confirm the central hypothesis of the study, that the feedback pathway between GDP and emissions is indirect and multistaged, and that there are stage delays among interlinked variables, which is additional to the system delay. This is possible due to the cybernetic transformation of a VECM system, which was previously not possible by relying only on econometric methods. The algorithm for VECM–cybernetic analysis can be written as:
Step 1: A qualitative analysis of the economic issue to be addressed and the selection of variables based on economic theories.
Step 2: Transforming the variables to their stationary form through unit root tests and determining the system delay via AIC and BIC methods.
Step 3: A cointegration analysis of the variables and constructing the error correction model via VECM or ARDL approaches.
Step 4: A qualitative analysis of the coefficients, based on the socioeconomics of the study region, and determining the feedback loops in the long run.
Step 5: Circuit elements like resistors, inductors, capacitors and op-amps should be utilized to represent an analogy of the feedback loop in Step 4.
Step 6: Determining the voltage input values of the op-amps and the coefficients of the resistors, capacitors, and inductors based on the associated VECM coefficient values in the feedback loop. (Note: Resistor value might be fixed since the coefficient and R-C circuits form a single equation)
Step 7: Performing a robustness analysis of the circuit by voltage or current testing, based on the economic analogy being explored.
It can be ascertained that a circuital representation can be an important economic policy tool for observing the delay among interlinked macroeconomic indicators explaining higher order behavior of economic systems, otherwise not analyzable using standard cointegration. It gives room for a diverse set of applications, as Step 1 and Step 4 are completely qualitative, showing the adaptability of this cybernetic approach. This also allows economists to socially engineer the point of policy introduction for a sustainable energy transition in developing economies despite economic shocks.
6. Conclusions and Implications
This paper can be distinctly divided into two important contributions and methodological angles: first, that decoupling is a dynamic process and causality in developing economies is not directly linked between economic growth and macrocarbon emissions; second, that modelled nexus systems contain feedback networks, which contain delays that can be represented by engineering analogous electronic circuits.
Decoupling is a dynamic and adaptive macroeconomic process, the causes of which are explored in this study in the context of the fast growing and high-inflation Indian economy. By tying together the Zivot–Andrews test, VECM, and long-run cointegration, the economic stress on decarbonization progress in the light of business cycle movements and economic shocks was analyzed from the period 1996 to 2020, with a quarterly time interval. It was found that internalizing inflation, trade openness, and FF imports into the same model can reveal linkages that can explain nonlinear economic complexities in 3E nexus systems. The main findings of this paper are as follows:
- (a)
The IPES loop wherein inventories are depleted due to rising inflation, which causes the capital to be replenished by FF imports, which increases long-run CO2 emissions.
- (b)
The whiplash effect wherein short-run emissions are increased by nonelectric, FF-intensive energy use, which further increases FF imports and inflation creating a multi-dimensional, short-run negative whiplash against decoupling.
- (c)
Capital enables decoupling in the high-inflation economy of India, with a 0.7% reduction of macro-emissions, while inflation is the largest inhibitor increasing emissions by 0.8% for every 1% rise in CPI.
- (d)
Electricity is coupled to FF imports in the long run with a coefficient of 0.248, while nonelectric energy is largely coupled to FF imports in the short run at 1.027.
The cybernetic analysis revealed that decoupling policies can be discretized. As a result, separate decoupling pathways can be followed during growth and recession periods in the macroeconomic cycles. Due to this, specific periods of policy interventions can be implemented that do not need to be perennial. In fact, perennial policies tend to be detrimental to energy transitions in the face of nonlinear economics, which can be mitigated by analogously transmuting the 3E system of any country to circuital form. In such a case, an input should always be assumed (either GDP or energy use) that can effectively control other macroeconomic factors preventing or propagating decoupling in respective business cycle phases. Some key policy implications from the cybernetic view are:
- (e)
Import tariffs ultimately shift the burden of macro-embodied emissions to the consumer, which hurts decoupling. Carbon taxation at the source should be introduced to boost both energy-transition-induced decoupling and energy security in India (discouraging short-run spikes of FF imports).
- (f)
When interest rates rise, FF imports should build capital for energy transition technologies. This will accelerate capital-based decoupling in recession phases and limit inflation-based coupling in growth phases. Capital building can be in the form of a domestic boost of RE technologies like giga-solar plants, electric vehicles in public transportation, smart cities, etc.
- (g)
From a market perspective, growth phases should accompany risk hedges, which can be incentivized in the form of green bonds to investors, which can limit inflation-emissions coupling during growth phases.
- (h)
Inflation control has to be tried by proactive and “early adjusted” decoupling resilient policies due to the macroeconomic system’s delay of effects. A policy tailored for growth, if implemented in a recession, can lead to the recoupling of emissions to the macroeconomy.
One limitation of the discretized cybernetic view of decoupling is that only delays among interlinked variables can be identified, while the magnitude cannot be replicated. Using these delay mechanisms, it can be easy for policymakers to examine the criticality of energy transition policies and enable control over an otherwise stochastic macroeconomic system. Immediate future studies could focus on how sectoral magnitudes of variables can be represented by cybernetic transformations of the economic systems with fewer variables. By merging electronics engineering with economic systems, studies can be employed to test various economic policies, such as waste management, auction dynamics for energy technologies, catalysis supply chain management for clean energy, etc.