ijeh International Journal of Energy Horizon (IJEH) 3108-3722 Ankara Yildirim Beyazit University Electrochemical Energy Storage and Conversion Energy Generation, Conversion and Storage (Excl. Chemical and Electrical) Elektrokimyasal Enerji Depolama ve Dönüşüm Enerji Üretimi, Dönüşüm ve Depolama (Kimyasal ve Elektiksel hariç) Alkaline Water Electrolysis: A Review on Technological Progress, Market Dynamics, and Environmental Implications Alkali Su Elektrolizi: Teknolojik Gelişmeler, Piyasa Dinamikleri ve Çevresel Etkiler Üzerine Bir İnceleme https://orcid.org/0000-0002-4137-7862 Çankaya Alperen ANKARA YILDIRIM BEYAZIT ÜNİVERSİTESİ, MÜHENDİSLİK VE DOĞA BİLİMLERİ FAKÜLTESİ, MAKİNE MÜHENDİSLİĞİ BÖLÜMÜ https://orcid.org/0000-0002-8472-9426 Kılıç Ahmed Emin ANKARA YILDIRIM BEYAZIT ÜNİVERSİTESİ, MÜHENDİSLİK VE DOĞA BİLİMLERİ FAKÜLTESİ, MAKİNE MÜHENDİSLİĞİ BÖLÜMÜ https://orcid.org/0000-0002-0186-6063 Kaplan Yüksel NİĞDE ÖMER HALİSDEMİR ÜNİVERSİTESİ, MÜHENDİSLİK FAKÜLTESİ, MAKİNE MÜHENDİSLİĞİ BÖLÜMÜ 11 30 2025 1 2 39 60 06 18 2025 10 17 2025 Copyright © 2025, International Journal of Energy Horizon (IJEH) 2025 International Journal of Energy Horizon (IJEH)

As global climate change continues to change rapidly, the development of sustainable and environmentally friendly energy technologies that can replace fossil fuels has become one of the top priorities in energy policy and research. Renewable energy sources such as geothermal, wind, and solar energy play a critical role in low-emission energy production; however, due to structural limitations such as intermittency and dependence on weather conditions, they cannot alone provide a continuous and reliable energy supply. In this context, hydrogen energy stands out as a strategic energy carrier that offers a solution to the intermittent nature of renewable energy sources, thanks to its high energy density, broad potential for use across different sectors, and long-term energy storage capacity. Green hydrogen, in particular, is of critical importance in terms of converting and storing excess renewable electricity production for reuse when needed. This eliminates the temporal mismatch between energy production and consumption, minimizing the carbon footprint of energy systems. Among current hydrogen production methods, alkaline water electrolysis (AWE) stands out due to its commercial maturity, relatively low investment and operating costs, stable operating performance, and ability to adapt to variable renewable energy inputs. Considering this, current developments in alkaline electrolyzer technologies are systematically examined in terms of principles, components and materials, performance optimization approaches, market dynamics, techno-economic assessments, and environmental and sustainable dimensions.

Küresel iklim değişikliği hızla değişmeye devam ederken, fosil yakıtların yerini alabilecek sürdürülebilir ve çevre dostu enerji teknolojilerinin geliştirilmesi, enerji politikası ve araştırmalarında en önemli önceliklerden biri haline gelmiştir. Jeotermal, rüzgar ve güneş enerjisi gibi yenilenebilir enerji kaynakları, düşük emisyonlu enerji üretiminde kritik bir rol oynamaktadır; ancak kesintili üretim ve hava koşullarına bağlılık gibi yapısal sınırlamalar nedeniyle, tek başlarına sürekli ve güvenilir bir enerji arzı sağlayamamaktadırlar. Bu bağlamda, hidrojen enerjisi, yüksek enerji yoğunluğu, farklı sektörlerde geniş kullanım potansiyeli ve uzun vadeli enerji depolama kapasitesi sayesinde yenilenebilir enerji kaynaklarının kesintili yapısına bir çözüm sunan stratejik bir enerji taşıyıcısı olarak öne çıkmaktadır. Özellikle yeşil hidrojen, ihtiyaç duyulduğunda yeniden kullanılmak üzere fazla yenilenebilir elektrik üretiminin dönüştürülmesi ve depolanması açısından kritik öneme sahiptir. Bu, enerji üretimi ve tüketimi arasındaki zaman uyumsuzluğunu ortadan kaldırarak enerji sistemlerinin karbon ayak izini en aza indirir. Mevcut hidrojen üretim yöntemleri arasında, alkali su elektrolizi (AWE), ticari olgunluğu, nispeten düşük yatırım ve işletme maliyetleri, istikrarlı işletme performansı ve değişken yenilenebilir enerji girdilerine uyum sağlama yeteneği nedeniyle öne çıkmaktadır. Bu bağlamda, alkali elektrolizör teknolojilerindeki güncel gelişmeler, prensipler, bileşenler ve malzemeler, performans optimizasyon yaklaşımları, pazar dinamikleri, tekno-ekonomik değerlendirmeler, çevresel ve sürdürülebilirlik boyutları açısından sistematik olarak incelenmektedir.

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