Liquid Organic Hydrogen Carriers (LOHCs) present a unique approach to hydrogen storage and transport by chemically binding hydrogen to organic molecules, enabling handling at ambient conditions. This method contrasts with compressed gas and liquid hydrogen storage, which rely on physical compression or cryogenic temperatures. Evaluating the economic viability of LOHCs requires analyzing capital costs, operational expenses, lifecycle performance, and key cost drivers such as catalyst efficiency and system scalability.

Capital costs for LOHC systems are influenced by the complexity of hydrogenation and dehydrogenation units. The hydrogenation process, which binds hydrogen to the carrier, requires reactors, heat exchangers, and catalysts. Dehydrogenation, the reverse process, demands similar infrastructure but operates at higher temperatures, increasing material costs. A typical LOHC system includes storage tanks, which are less expensive than high-pressure or cryogenic tanks since they operate at ambient conditions. However, the need for specialized catalysts and thermal management systems adds to upfront expenses. For compressed hydrogen storage, capital costs are dominated by high-pressure vessels (350–700 bar) and compressors, while liquid hydrogen systems incur expenses for cryogenic tanks and liquefaction plants, which are energy-intensive.

Operational expenses for LOHCs stem from energy inputs during hydrogenation and dehydrogenation. Dehydrogenation, in particular, requires significant heat, often exceeding 250°C, raising energy costs. The longevity and efficiency of catalysts are critical; degradation over time necessitates replacement, adding to operational costs. In contrast, compressed hydrogen systems face ongoing costs from electricity used in compression, while liquid hydrogen systems incur high energy penalties for liquefaction, consuming approximately 30% of the stored hydrogen’s energy content. LOHCs avoid the daily boil-off losses associated with liquid hydrogen, which can range from 0.5% to 1% per day, but their energy-intensive release process offsets some of this advantage.

Lifecycle analysis reveals trade-offs between these storage methods. LOHCs exhibit lower embodied energy in storage tanks compared to high-pressure or cryogenic vessels, but their overall efficiency is hampered by the round-trip energy losses in hydrogenation and dehydrogenation, typically around 60–70%. Compressed hydrogen systems achieve higher round-trip efficiency (70–80%) but suffer from energy losses during compression. Liquid hydrogen systems have the lowest round-trip efficiency (50–60%) due to liquefaction losses. The lifecycle carbon footprint of LOHCs depends on the energy source for hydrogenation and dehydrogenation; renewable energy reduces emissions significantly, while fossil-based heat increases them.

Cost drivers for LOHCs include catalyst performance and system scale. Catalysts based on platinum-group metals are effective but expensive, prompting research into alternatives like ruthenium or nickel-based compounds. Catalyst lifespan directly impacts operational costs; current systems require replacement every few years. Scaling LOHC systems could reduce costs through economies of scale, particularly in hydrogenation and dehydrogenation units, but achieving this demands standardized carrier molecules and optimized reactor designs. Compressed hydrogen benefits from mature technology and scaling effects in compressor manufacturing, while liquid hydrogen costs are tied to advancements in liquefaction efficiency.

Comparing storage densities highlights another economic factor. LOHCs typically store hydrogen at 5–7% by weight, comparable to compressed gas at 700 bar (5–6% by weight) but lower than liquid hydrogen (7–9% by weight). However, LOHCs enable safer, denser storage at ambient conditions, reducing infrastructure costs for transport and handling. Compressed hydrogen requires heavy, high-pressure tanks, while liquid hydrogen needs continuous refrigeration, adding complexity.

The choice between these methods depends on application-specific requirements. LOHCs excel in long-distance transport and long-term storage where energy penalties are acceptable, while compressed hydrogen suits short-range mobility with frequent refueling. Liquid hydrogen is favored in aerospace and heavy transport where weight and volume are critical, despite higher costs.

Material compatibility and system integration also affect economics. LOHCs must avoid side reactions during hydrogenation and dehydrogenation, requiring pure carrier molecules and careful process control. Compressed hydrogen systems face challenges with hydrogen embrittlement, necessitating high-grade materials. Liquid hydrogen systems demand insulation to minimize heat ingress, adding to costs.

In summary, LOHCs offer a viable alternative to compressed and liquid hydrogen storage, particularly in scenarios prioritizing safety and handling simplicity. Their economic competitiveness hinges on reducing catalyst costs, improving energy efficiency, and scaling production. While they may not surpass compressed hydrogen in applications requiring rapid refueling or liquid hydrogen in energy density-critical uses, LOHCs fill a niche in decentralized and transport-oriented hydrogen economies. The decision to adopt LOHCs should weigh these factors against operational needs and infrastructure constraints.