This study aims to observe the long run and short run effects of gross domestic product, foreign direct investment inflows and trade on CO2 emissions and causality relationships between these factors, using annual data for the period of 1974-2010. The empirical results demonstrate that the inverted U-shaped relationship of environmental Kuznets curve is valid for Turkey. In addition, there are positive long run effects of foreign direct investment and trade openness on CO2 emissions. The authors also find a bidirectional causality relationship between CO2 emission and FDI.

Developing countries are trying to improve the competitiveness of the energy markets with continuous liberalization. This makes the market highly sensitive. Every player in the market has a greater need to know about the smallest change in the market. Hence, ability to see what is ahead is a valuable advantage to make the right move. A time series forecasting with the smallest errors would be a powerful tool for the energy producers. This paper proposes combined methodology in time series forecasting. Generally accepted and widely used ARIMA and ANN with backpropagation learning are combined. The methodology is implemented for the day-ahead Turkish power market. It is observed that the proposed methodology gives results with reduced errors. The achievements are compared with conventional use of both ARIMA and ANN.

This study shows the adequacy of power systems that can incorporate renewable energy sources and hydrogen for large-scale power consumption. Using the Analytic Hierarchy Process with a focus on multiple criteria, six grid-scalable energy storage technologies are initially assessed to this end. The most suitable option for grid-scale application is green hydrogen storage technology. Then, an optimization model is developed to advance hydrogen solutions by minimizing the annual cost equivalent to capital and operational expenditures of the systems. The model is used to comprehensively examine the integration and operation of two distinct real-life applications: hybrid power systems that incorporate hydrogen alongside renewable energy sources (i) without natural gas and (ii) with natural gas. In this direction, this study thoroughly examines the crucial role of green hydrogen in achieving a sustainable and clean energy landscape through a multidisciplinary investigation of hydrogen production and storage from a technology management perspective. Through case studies, the practicality of integrating green hydrogen into power systems to meet substantial power demands is shown. By decreasing the systems’ current costs by ∼60% and contributing to an increase in renewable energy penetration, the proposed systems provide cost-effectiveness, carbon reduction potential, and adaptability to existing infrastructure. In response to the imperative to overcome challenges in transitioning to cleaner energy, this research advocates for well-informed decision-making by using the optimization model to attain a robust and ecofriendly energy future.