Spatial variability of green hydrogen in Türkiye: Environmental and economic perspectives

Human activities have significantly increased greenhouse gas (GHG) emissions, accelerating climate change and raising atmospheric CO₂ levels by nearly 50 % since the Industrial Revolution, primarily due to fossil fuel use and deforestation. This has driven a 1.1 °C rise in global temperatures, with projections suggesting that continued emissions could push temperatures beyond the 1.5 °C threshold by the 2030s, triggering severe consequences such as extreme weather events, biodiversity loss, and ice melt. Mitigating these risks requires reducing reliance on fossil fuels, with green hydrogen emerging as a promising solution by providing a clean, carbon-free fuel source [1].

Green hydrogen, produced through water electrolysis powered by renewable sources such as wind and solar, produces no carbon dioxide emissions during its generation. Its potential to decarbonize hard-to-electrify sectors, like heavy industry and aviation—accounting for approximately 23 % of global CO₂ emissions—is significant [2]. Replacing fossil-based hydrogen with green hydrogen could prevent 830 million tons of CO₂ emissions annually, equivalent to Germany’s total annual emissions, contributing to a 20 % reduction in global emissions by 2050 [3].

Unlike grey hydrogen, which relies on natural gas, and blue hydrogen, which captures partial emissions, green hydrogen is entirely produced using renewable energy, eliminating carbon emissions during production. Although it is currently more expensive, advancements in electrolyzer efficiency and renewable energy integration are expected to reduce costs, making production more competitive [4]. By 2050, hydrogen could meet 12 % of global energy demand, with green hydrogen playing a pivotal role. Regions with abundant renewable resources, such as North Africa and Australia, are poised to become key exporters, while high-demand countries with limited renewables, such as Japan and parts of Europe, are likely to rely on imports. This global market, projected to generate over $280 billion annually, could enhance energy security and economic growth, especially in developing economies [4,5].

Türkiye’s diverse geography and climate offer unique opportunities for optimizing green hydrogen production, positioning it as a key player in the global transition to renewable energy. While previous studies on Life Cycle Assessment (LCA) and Life Cycle Cost Assessment (LCCA) of hydrogen production have provided valuable insights, most focus on national or single-location analyses with constant capacity factors for wind and solar energy. These approaches overlook regional variations in renewable potential, especially under different climate scenarios.

This study addresses this gap by integrating grid-specific environmental and economic evaluations of green hydrogen production within a high-resolution, climate-informed framework tailored to Türkiye. By segmenting Türkiye into 120 grid cells (1° × 1° resolution) and utilizing regridded Global Climate Models (GCMs), the research captures spatial variations in temperature, wind speed, and solar irradiance.

Given Türkiye’s diverse climatic conditions and topography, regional variability in renewable energy availability significantly affects the feasibility of green hydrogen production. To address this, the present study incorporates spatially resolved projections from multiple GCMs, ensuring that regional disparities in solar and wind energy potential are accurately captured under future climate scenarios. This spatial differentiation allows for robust planning that aligns hydrogen production infrastructure with areas of highest technical and economic viability. This geographically nuanced approach enables robust estimations of renewable energy output, forming a reliable basis for policy and investment decisions.

The methodology combines LCA and LCCA with an optimization model that determines the optimal capacities of wind and solar installations for each grid, minimizing levelized costs for a 10 MW Proton Exchange Membrane Electrolyzer (PEMEC) system. Policy scenarios, including tax credits and investment incentives, are also evaluated to assess their economic impact and identify strategies for improving the financial feasibility of green hydrogen production.

The environmental impacts associated with green hydrogen production are a subject of considerable interest in research that uses LCA and LCCA to determine the feasibility of alternative energy systems. While a wide range of sustainable hydrogen production techniques have been examined for their environmental consequences, this review specifically highlights analyses of green hydrogen production pathways reliant on solar and wind energy.

For instance, Cetinkaya et al. [6] conducted a comparative analysis of five hydrogen production routes. Their study shows that although wind and solar electrolysis are environmentally friendly, they are less efficient in terms of production capacity. Building on this, Zhang et al. [7] assessed three electrolysis technologies—alkaline (AEC), PEMEC, and solid oxide (SOEC)—using wind power as the energy source. Their results demonstrate that PEM electrolysis, especially when combined with onshore wind, achieves the lowest global warming potential (GWP), reinforcing its environmental benefits. Similarly, Patel et al. [8] compared hydrogen production routes such as grey, blue, turquoise, and green hydrogen. They found that green hydrogen produced from wind energy results in the lowest emissions, while fossil-fuel-derived hydrogen yields much higher emissions.

Delpierre et al. [9] took an ex-ante LCA approach to evaluate large-scale AEL and PEM systems. They found that electricity generation accounts for over 90 % of the total environmental impact, stressing the importance of renewable electricity in minimizing emissions. More recently, Shen et al. [10] also highlighted the benefits of large-scale green hydrogen deployment for reducing climate impacts. However, their study warned that this shift may place additional pressure on resources such as land and minerals due to increased infrastructure demands.

Other studies, such as those by Vilbergsson et al. [11] and Pawlowski et al. [12], examine regional and technological innovations. Vilbergsson et al. [11] compared the GWP of hydrogen production in Iceland with that of European locations, demonstrating Iceland’s advantage due to its renewable energy sources (RES). Pawlowski et al. [12], on the other hand, explored the use of AEM electrolysis powered by solar energy in Poland, showing low carbon emissions but also emphasizing the economic challenges associated with this emerging technology, which relies on external subsidies for competitiveness.

In addition to LCA studies, numerous studies have also focused on the LCCA of green hydrogen production. Nasser et al. [13] explored a hybrid system of wind turbines and photovoltaic panels to generate green hydrogen through water electrolysis, analyzing five different power generation scenarios in Egypt’s Mersa-Matruh region. The study emphasized the impact of seasonal variations in solar radiation and wind speed, highlighting potential CO₂ reductions of 345 tons and a total financial gain of 13,806 USD over the system’s lifetime. In a related study, Nasser and Hassan [14] explored hydrogen production through PEM and SOEC electrolyzers, assessing the impact of various energy inputs encompassing PV systems, wind power, waste heat utilization, and electricity from the grid. Their sensitivity analysis revealed that waste heat systems offered the highest efficiency and the lowest LCOH, while PV systems showed lower efficiency.

Additionally, Gül and Akyüz [15] evaluated the feasibility of PV-powered hydrogen production in Turkey, estimating that costs could drop from 6.8 USD/kg in 2023 to 5.87 USD/kg by 2050 with improved electrolyzer efficiency. Similarly, Srettiwat et al. [16] compared hydrogen production in Belgium with imports from Morocco and Namibia, finding that importing from Namibia was more cost-effective, while Schmidhalter et al. [17] optimized LCOH for wind-powered hydrogen production in Argentina, Chile, and other global sites.

Alongside experimental and modeling research, a growing number of review articles offer comprehensive insights into hydrogen production technologies, their environmental performance, and commercialization potential. These reviews integrate findings from various studies, providing a broad perspective on the sustainability, cost-efficiency, and technological advancements in green hydrogen production. Notable reviews by Ji and Wang [18], Cho et al. [19], Chelvam et al. [20], and Ajeeb et al. [21] discuss both the progress and ongoing challenges in hydrogen production, highlighting the crucial role of renewable energy in enhancing environmental outcomes.

Furthermore, Chavez et al. [22] reviewed literature from 2019 to 2023 on green hydrogen systems and found that while LCA and multi-objective optimization are being used, integrated studies often lack detailed environmental analysis and consideration of end-of-life impacts, typically employing simplified bi-objective approaches focused on economic and carbon metrics. Together, these studies contribute to a deeper understanding of how green hydrogen can be optimized to meet future energy demands while minimizing its environmental footprint.