The relationships between renewable energy, net energy imports, arms exports, military expenditures, and CO2 emissions in the USA.

We evaluate the relationships between renewable energy consumption, net energy imports, military expenditures, arms exports, gross domestic product, and carbon dioxide emissions by using annual data about the USA. The autoregressive distributed lag approach and the vector error correction model are used. There are both long-run and strong causalities running from all considered variables to renewable energy consumption. In addition, we have a short-run causality running from net energy imports to renewable energy consumption. We show that arms exports have a positive long-run effect on both renewable energy consumption and net energy imports. Military expenditures have a positive long-term effect on renewable energy consumption, but they have a negative long-term effect on both net energy imports and CO2 emissions. This study shows that the military sector is contributing to using renewable energy and combatting global warming in the USA. We recommend increasing the R&D budget of the US Department of Defense allocated to innovations in renewable energies.

Inspecting the influence of renewable energy and R&D in defending environmental quality: evidence for California.

The United Nations's Sustainable Development Goals (SDGs) is international cooperation that aims to climate change mitigation, and encourage the use of clean energy. Investing in green technology to reduce carbon dioxide (CO2) emissions is among the most important objective of the SDGs. As the USA is part of this collaboration, the present study tries to examine the progress of one State to meet the Global Goals. This paper uses the autoregressive distributed lags (ARDLs) approach and Granger causality test to evaluate the dynamic relationships uniting gross domestic product (GDP), CO2 emissions, renewable energy consumption (REC), and research and development (R&D) for the California State over the period 1987-2017. The outcome of the econometric analysis proved that REC affects CO2 emissions in the short run, and vice versa. In addition, a bidirectional relationship is detected between GDP and R&D and CO2 emissions and REC Granger causes GDP. In the long run, REC, R&D, and GDP Granger cause CO2 emissions, while REC, R&D, and CO2 emissions Granger cause GDP. We also found a bidirectional causality linking CO2 emissions and GDP. The long-run elasticities show that R&D and GDP impact positively CO2 emissions whereas REC affects it. Thus, R&D increases pollution but REC reduces it. Environmental degradation is perhaps related to the excessive consumption of fossil energy in most activities. California is advised to enhance the effort to meet the SDGs. Encouraging R&D of low carbon technologies and applying several taxations for non-renewable fuel adoption may also constitute a useful strategy to protect the environment.

Exploring the role of renewable energy and foreign and non-foreign patents on mitigating emissions: evidence for Tunisian economy.

This study investigates the relationships among renewable energies (RE), carbon dioxide (CO2) emissions, foreign direct investment (FDI), foreign and non-foreign patents (FP, NFP), and trade (TR) for the case of Tunisia using time series data spanning the period 1980-2017. The autoregressive distributed lags (ARDL) model approach of Pesaran et al. (J Appl Econ 16:289-326, 2001) and the causality of Granger are employed to explore the dynamic association between the underlined variables. The results from the long-run elasticities show that FDI and TR have negative and statistically significant impacts on RE, while NFP has a positive and statistically significant effect on the consumption of RE. Both FP and CO2 emission variables are insignificant in the long run. In the short run, there are no Granger causal links between RE and patents (FP and NFP), but we have one-way causality running from CO2 emissions to patents (FP and NFP). In the long run, there are bidirectional causalities between RE, NFP, and TR. The Tunisian authorities must impose more stringent environmental standards to attract foreign investments that are more respectful of the environment, and import and export cleaner. It is also necessary to encourage R&D and innovation which appear to be beneficial for the environment.

Non-resident and resident patents, renewable and fossil energy, pollution, and economic growth in the USA.

The main objective of this paper is to estimate the impact of foreign research and development (R&D) spillovers on pollution and renewable energy consumption (RE). We choose as proxies for R&D and for foreign R&D spillovers, resident patents (RP) and non-resident patents (NRP), respectively. We use annual data for the USA spanning the period 1980-2016. We show the presence of a long-run relationship between NRP, RP, RE, fossil energy consumption (FE), net energy imports (NEI), gross domestic product (GDP), and carbon dioxide (CO2) emissions. There are long-run unidirectional Granger causalities running from all considered variables to economic growth. There are short-run unidirectional causalities running from NEI to all considered variables except RP and GDP, from GDP to RP and RE, from FE to RE, and from carbon emissions to RE. By using the autoregressive distributed lag approach, several long-run elasticities are evaluated. In particular, RP increases carbon emissions, whereas NRP reduces it. Both RP and NRP have a positive impact on RE and GDP. RP and NRP seem to be complementary activities, and RE reduces NEI. Therefore, the US authorities should encourage the use of NRP because of their beneficial effect on pollution, home innovation, renewable energy consumption, and economic growth.

Economic growth, combustible renewables and waste consumption, and CO2 emissions in North Africa.

This paper uses panel cointegration techniques and Granger causality tests to examine the dynamic causal link between per capita real gross domestic product (GDP), combustible renewables and waste (CRW) consumption, and CO2 emissions for a panel of five North African countries during the period 1971-2008. Granger causality test results suggest short- and long-run unidirectional causalities running from CO2 emissions and CRW consumption to real GDP and a short-run unidirectional causality running from CRW to CO2 emissions. The results from panel long-run fully modified ordinary least squares (FMOLS) and dynamic ordinary least squares (DOLS) estimates show that CO2 emissions and CRW consumption have a positive and statistically significant impact on GDP. Our policy recommendations are that these countries should use more CRW because this increases their output, reduces their energy dependency on fossil energy, and may decrease their CO2 emissions.

The dynamic interaction between combustible renewables and waste consumption and international tourism: the case of Tunisia.

This paper employs the autoregressive distributed lag (ARDL) bounds methodological approach to investigate the relationship between economic growth, combustible renewables and waste consumption, carbon dioxide (CO2) emissions, and international tourism for the case of Tunisia spanning the period 1990-2010. The results from the Fisher statistic of both the Wald test and the Johansen test confirm the presence of a long-run relationship among the variables under investigation. The stability of estimated parameters has been tested, while Granger causality tests recommend a short-run unidirectional causality running from economic growth and combustible renewables and waste consumption to CO2 emissions, a bidirectional causality between economic growth and combustible renewables and waste consumption and unidirectional causality running from economic growth and combustible renewables and waste consumption to international tourism. In the long-run, the error correction terms confirm the presence of bidirectional causality relationships between economic growth, CO2 emissions, combustible renewables and waste consumption, and international tourism. Our long-run estimates show that combustible renewables and waste consumption increases international tourism, and both renewables and waste consumption and international tourism increase CO2 emissions and output. We recommend that (i) Tunisia should use more combustible renewables and waste energy as this eliminates wastes from touristic zones and increases the number of tourist arrivals, leading to economic growth, and (ii) a fraction of this economic growth generated by the increase in combustible renewables and waste consumption should be invested in clean renewable energy production (i.e., solar, wind, geothermal) and energy efficiency projects.