Energy consumption, technological innovation, and environmental degradation in SADC countries

Figures & data

Figure 1. Theoretical framework of EKC.

Source: Zhang et al., 2022.

Table 1. Definition and source of variables.

Variable	Definition	Expected A priori	Source
C02pc	Carbon dioxide emissions are those stemming from the burning of fossil fuels and the manufacture of cement. They include carbon dioxide produced during consumption of solid, liquid, and gas fuels and gas flaring.		Global Economy Database (GED)
Apec	Energy consumption refers to primary energy before transformation to other end-use fuels, equal to indigenous production plus imports and stock changes, minus exports and fuels supplied to ships and aircraft engaged in international transport.	positive	GED
TI_Fbs	The broadband subscribers (fbs), which measures technology penetration or access to internet speed– refers to the number of households and organizations with fixed subscriptions per 100 individuals at a rate greater than or equal to 256 bits/second.	negative	GED
TI_itu	Internet usage refers to the number of individuals who have used the Internet (from any location) in the last three months. The Internet can be used via a computer, mobile phone, personal digital assistant, games machine, digital TV, etc.	negative	GED
TI_mcs	The mobile cellular subscription (mcs) refers to all subscriptions paid for public mobile telephone services per 100 individuals.	negative	GED
TI_ict	Is the technology index value generated through PCA computed using the PCA from fixed broadband subscription, internet use, and mobile phone usage data	negative	GED
Inst	Is the institutional index computed using PCA from six indicators of institutional quality, including the rule of law, government effectiveness, control of corruption, regulatory quality, voice accountability, and political stability data—the values of the six components range from −2.5 weak to 2.5 strong.	negative	Author’s calculations of institutional quality composites with data from the GED database
Rgdp	Real Gross domestic product (% annual)	negative	World Bank
Kof	Economic globalization has two dimensions: actual economic flows and restrictions to trade and capital. The sub-index on actual economic flows includes trade, FDI, and portfolio investment data. The sub-index on restrictions takes into account hidden import barriers, mean tariff rates, taxes on international trade (as a share of current revenue), and an index of capital controls.		World Integrated Trade Solutions (WITS)
Hci	Human capital index: based on years of schooling and return to education	negative	World Penn Tables
Acte	Access to electricity is the percentage of the population with access to electricity. Electrification data are collected from industry, national surveys, and international sources.	positive
urbn	Urbanisation: Percentage (%) of people living in urban areas	positive	GED
Fdi	Foreign direct investment, net inflows (% GDP)	positive/negative	International Monetary Fund
Cp	The Corruption Perceptions Index indicates perceptions of public sector corruption, that is, administrative and political corruption.	negative	GED
Pls	The Index of Political Stability and Absence of Violence/Terrorism	negative	GED
Cil	The Civil Liberties Index indicates freedom of expression and belief, associational and organizational rights, rule of law, personal autonomy, and individual rights. The rating ranges from 1 (strong liberties) to 7 (no liberties).	negative	GED

Source: Author’s compilation from STATA.

Table 2. Summary statistics of variables.

Variable	Obs	Mean	Std. dev	Min	Max
lC02pc	400	.8679822	.8359811	.0199987	2.903334
lapec	417	1.01184	2.23749	−4.217369	5.653589
lfbs	276	.7328891	1.042271	0	4.35096
litu	444	2.083059	1.620681	0	5.094892
lmcs	447	3.305107	2.016757	0	5.916533
lict	274	.2586813	.9710939	−.9822264	2.72238
linst	352	.0001648	1.368111	−2.438916	2.124998
lrgdp	448	1.570556	1.512713	−3.565815	3.759415
lkof	430	4.556746	.2554543	3.868716	5.138066
lhci	364	1.383679	.2116514	.9595914	1.798919
lacte	383	4.074506	.8967651	1.060026	5.298342
lurbn	432	4.243794	.3892779	3.252646	4.954185
lfdi	416	.3930039	.7074817	−2.699162	3.001204
lcp	288	4.196915	.3520928	3.402307	4.882859
lpls	352	−.0700293	.6736369	−1.766598	1.066198
lcil	432	1.964759	.355857	.8813736	2.644121

Note. C02pc is the carbon emissions per capita; apec-annual primary energy consumption; fbs- fixed broad subscription; itu-internet usage; mcs -mobile phone subscription; ict-the information communication technology index; inst -institutional quality index; rgdp-real gross domestic product; kof-economic globalisation; hci-human capital index; acte-access to electricity; urbn-urbanisation; fdi-foreign direct investment; cp-corruption perception index; pls-political stability; cil-civil liberties.

Source: Author’s compilation from STATA.

Table 3. Correlation coefficient test results.

	lC02pc	lapec	lfbs	litu	lmcs	lict	linst
lC02pc	1.0000
lapec	−0.0569*	1.0000
lfbs	0.6582*	−0.0590*	1.0000
litu	0.5465*	−0.0713*	0.7072*	1.0000
lmcs	0.3991*	−0.0066	0.5752*	0.9158*	1.0000
lict	0.7158*	−0.1077*	0.8724*	0.9266*	0.7878*	1.0000
linst	0.6619*	0.0129	0.5490*	0.3448*	0.2813*	0.5215*	1.0000
lrgdp	−0.0877*	0.2370*	−0.1015*	−0.1307*	−0.0168	−0.1852*	0.0544*
lkof	0.5626*	0.0554*	0.6080*	0.4143*	0.3816*	0.5326*	0.6942*
lhci	0.2303*	−0.0871*	−0.1442*	0.2449*	0.2761*	0.0857*	0.1898*
lacte	0.7212*	−0.0651*	0.6443*	0.6622*	0.5437*	0.7074*	0.3872*
lurbn	0.6459*	−0.0324	0.4090*	0.4207*	0.3897*	0.4686*	0.3078*
lfdi	0.1486*	0.0705*	0.0100	0.1541*	0.2482*	0.0332	0.0907*
lcp	0.6696*	−0.0251	0.6007*	0.5305*	0.5070*	0.6254*	0.9064*
lpls	0.4744*	0.0814*	0.4736*	0.3064*	0.2540*	0.4045*	0.8541*
lcil	−0.5883*	−0.0762*	−0.4011*	−0.3543*	−0.3214*	−0.4076*	−0.9084*
	lrgdp	lkof	lhci	lacte	lurbn	lfdi	lcp
lrgdp	1.0000
lkof	0.0856*	1.0000
lhci	−0.0589*	0.0590*	1.0000
lacte	−0.1054*	0.3428*	0.0948*	1.0000
lurbn	−0.0884*	0.3370*	0.2170*	0.6510*	1.0000
lfdi	0.1600*	0.1435*	0.2685*	0.0602*	0.2329*	1.0000
lcp	−0.0689*	0.6764*	0.2666*	0.5244*	0.3063*	0.0599*	1.0000
lpls	0.0847*	0.6082*	0.1782*	0.3784*	0.2041*	−0.1058*	0.7678*
lcil	−0.0656*	−0.5402*	−0.1890*	−0.3765*	−0.3270*	−0.1879*	−0.8043*
	lpls	lcil
lpls	1.0000
lcil	−0.7461*	1.0000

Source: Author’s compilation from STATA.

Table 4. Stationary tests test results.

Method	IM Pesaran		ADF
Order of integration	1(0)	1(1)	1(0)	1(1)
Variable	t-stat	t-stat	t-stat	t-stat
lC02pc	1.637	−9.663***	2.198	−14.070***
lapec	−11.078	−13.661***	−15.530	−24.169***
lfbs	−3.507	−5.698***	2.493	−7.481***
litu	8.676	−6.536***	2.014	−7.599***
lmcs	−2.574***	−6.792***	7.561	−6.876***
lict	6.894	−3.589	4.442	−3.681***
linst	0.330	−8.219***	−1.659**	−11.974***
lrgdp	−9.494***	−14.062***	−13.231***	−24.095***
lkof	−2.597***	−10.820***	−0.667	−15.320***
lhci	4.297	−2.303***	−4.376***	−2.807***
lacte	−1.061	12.195***	−7.394***	−21.589***
lurbn	5.937	0.635	−4.460***	0.532*
lfdi	−4.614***	−12.429***	−5.611***	−21.114***
lcp	−1.450*	−7.167***	−0.847	−9.050***
lpls	−3.549***	−9.454***	−3.293***	−16.123***
lcil	−1.990***	−2.610**	−0.729	−13.557**

***p < 0.01, **p < 0.05, *p < 0.1.

Source: Author’s compilation from STATA unit root test results.

Table 5. Diagnostic results.

Hausman test results
	fbs	itu	mcs	ict	apecfbs	apecitu	apecmcs	apecict
Chi2(12)	145.37	23.38	562.09	266.85	288.34	189.85	171.02	261.19
P-value	0.0000	0.0247	0.0000	0.0000	0.0000	0.0000	0.0000	0.0000
Cross-sectional dependance test results
Pesaran cross-sectional dependence test
	fbs	itu	mcs	ict	apecfbs	apecitu	apecmcs	apecict
P-test	−1.269	1.387	−1.696	−0.707	−1.007	−1.393	−1.761	−0.668
Absolute val	0.365	0.377	0.381	0.360	0.353	0.377	0.378	0.359
P value	0.2045	0.1655	0.0898	0.4798	0.3138	0.1637	0.0783	0.5044
Friedman cross-sectional dependence test
	fbs	itu	mcs	ict	apecfbs	apecitu	apecmcs	apecict
F-test	0.429	9.229	5.269	0.429	0.5149	9.486	5.843	0.343
Absolute val	0.530	0.367	0.396	0.523	0.522	0.367	0.398	0.518
P value	1.000	0.7555	0.9586	1.000	1.000	0.7354	0.9517	1.000
Wald heteroscedasticity test
Chi2	36188.24	346.03	633.44	5492.01	41171.34	345.42	604.74	6870.40
P-value	0.0000	0.0000	0.0000	0.0000	0.0000	0.0000	0.0000	0.0000
Wooldridge serial correlation test
F(1,13)	2.052	2.326	2.251	1.886	2.037	3.147	2.571	2.335
P-value	0.756	0.1521	0.1574	0.1929	0.1771	0.0995	0.1329	0.1504
Jaque-Bera normality test
JB test	3.174	4.290	4.555	2.794	2.622	4.525	4.545	2.513
P-value	0.2046	0.1195	0.1025	0.2473	0.2696	0.1041	0.1031	0.2846

Source: Author’s compilation from STATA.

Table 6. The impact of energy consumption on environment degradation.

Variables	(Model_1)	(Model_2)	(Model_3)	(Model_4)	(Model_5)	(Model_6)	(Model_7)	(Model_8)
	(FGLS)	(FGLS)	(FGLS)	(FGLS)	(FGLS)	(FGLS)	(FGLS)	(FGLS)
	lC02pc	lC02pc	lC02pc	lC02pc	lC02pc	lC02pc	lC02pc	lC02pc
lapec	0.0173	0.0127	0.0121	0.0180	0.0287**	0.0510**	0.0917**	0.0167
	(0.0117)	(0.0114)	(0.0113)	(0.0117)	(0.0137)	(0.0231)	(0.0389)	(0.0115)
linst	0.732***	0.498***	0.480***	0.742***	0.743***	0.515***	0.504***	0.756***
	(0.0887)	(0.0803)	(0.0825)	(0.0884)	(0.0884)	(0.0801)	(0.0824)	(0.0874)
lrgdp	−0.0389**	−0.0255	−0.0235	−0.0400**	−0.0421**	−0.0306*	−0.0340*	−0.0473***
	(0.0178)	(0.0176)	(0.0178)	(0.0178)	(0.0178)	(0.0176)	(0.0183)	(0.0178)
lkof	−0.235	−0.0583	−0.0651	−0.215	−0.213	−0.0467	−0.0536	−0.204
	(0.168)	(0.162)	(0.162)	(0.165)	(0.167)	(0.161)	(0.160)	(0.163)
lhci	0.471***	0.363***	0.371***	0.444***	0.442***	0.348***	0.363***	0.412***
	(0.124)	(0.121)	(0.121)	(0.121)	(0.125)	(0.121)	(0.120)	(0.120)
lacte	0.653***	0.628***	0.649***	0.639***	0.657***	0.637***	0.651***	0.661***
	(0.0593)	(0.0637)	(0.0541)	(0.0605)	(0.0590)	(0.0634)	(0.0535)	(0.0604)
lurbn	0.216**	0.243***	0.239***	0.211**	0.197**	0.222***	0.224***	0.171**
	(0.0863)	(0.0814)	(0.0793)	(0.0856)	(0.0866)	(0.0815)	(0.0789)	(0.0862)
lfdi	−0.0919***	−0.0734**	−0.0700**	−0.0902***	−0.0911***	−0.0711**	−0.0714**	−0.0852***
	(0.0316)	(0.0311)	(0.0315)	(0.0314)	(0.0314)	(0.0309)	(0.0312)	(0.0310)
lcp	−0.814***	−0.372**	−0.324*	−0.869***	−0.831***	−0.390**	−0.373**	−0.888***
	(0.191)	(0.174)	(0.181)	(0.196)	(0.191)	(0.172)	(0.180)	(0.194)
lpls	−0.730***	−0.606***	−0.597***	−0.728***	−0.727***	−0.610***	−0.601***	−0.723***
	(0.0831)	(0.0790)	(0.0798)	(0.0829)	(0.0826)	(0.0784)	(0.0791)	(0.0818)
lcil	0.127	−0.111	−0.130	0.133	0.163	−0.0753	−0.0834	0.178
	(0.183)	(0.176)	(0.177)	(0.182)	(0.184)	(0.176)	(0.176)	(0.181)
lfbs	0.0402				0.0834*
	(0.0404)				(0.0486)
litu		0.00406				0.0175
		(0.0289)				(0.0295)
lmcs			−0.0171				0.00781
			(0.0259)				(0.0282)
lict				0.0571				0.0849**
				(0.0409)				(0.0421)
Interaction Terms
lapeclfbs					−0.0298
					(0.0189)
lapeclitu						−0.0160*
						(0.00844)
lapeclmcs							−0.0189**
							(0.00882)
lapeclict								−0.033**
								(0.0144)
Constant	0.838	−1.228	−1.368	1.106	0.833	−1.233	−1.321	1.182
	(1.146)	(1.059)	(1.065)	(1.175)	(1.139)	(1.051)	(1.055)	(1.159)
Observations	191	226	226	191	191	226	226	191
Number of countrynum	14	14	14	14	14	14	14	14

Standard errors in parentheses.

***p < 0.01, **p < 0.05, *p < 0.1.

Source: Author’s compilation from STATA.

Zhang, Z., Bashir, T., Song, J., Aziz, S., Yahya, G., Bashir, S., & Zamir, A. (2022). The effects of Environmental Kuznets Curve toward environmental pollution, energy consumption on sustainable economic growth through moderate role of technological innovation. Environmental Science and Pollution Research, 29(1), 405–416. https://doi.org/10.1007/s11356-021-16956-y

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Data availability statement

Data that supports the findings of this study is available on request from the corresponding author. The data was sourced from theglobaleconomy database which is a credible data source.