solid hydrogen battery for residential solar energy storage.

Annexe : realistic ? 

The concept of a solid hydrogen battery for residential solar energy storage as described by Photoncycle sounds very innovative, but there are several factors to consider when evaluating its realism and feasibility:

1. Technology Maturity: Solid hydrogen storage technology is still in the experimental stages. While hydrogen is a promising energy carrier, storing it in solid form involves complex chemical reactions and materials engineering. The transition from laboratory or small-scale prototypes to full-scale residential systems involves significant challenges.
2. Energy Density Claims: The claimed energy density of 3.5 kW/kg is significantly higher than current lithium battery technologies. Achieving this level of energy density with hydrogen in a solid and safe form for residential use would be a major advancement, but it also raises questions about the scalability and real-world application of the technology.
3. System Integration: Integrating such a system into existing residential infrastructure, including solar panel setups and home heating systems, requires compatibility and safety considerations. This includes ensuring the system can operate efficiently without posing risks, such as those associated with hydrogen handling.
4. Cost and Economic Viability: The startup claims that the cost of storing energy will be particularly low, which is crucial for widespread adoption. However, the initial investment for such systems and the long-term maintenance costs need to be evaluated. Often, new technologies can be expensive initially, even if they promise lower operational costs.
5. Regulatory and Safety Approvals: Given that the technology involves hydrogen, a highly flammable substance, obtaining necessary safety certifications and regulatory approvals can be complex and time-consuming.
6. Market Readiness: The projected market launch by 2025 suggests an aggressive timeline. The readiness of the market, as well as the production and distribution capacities of Photoncycle, will be critical factors in determining the success of this venture.

In summary, while the concept of a solid hydrogen battery for solar energy storage by Photoncycle is certainly promising and represents a potential leap forward in energy storage technology, its realism and feasibility will depend heavily on overcoming technological, economic, regulatory, and market challenges.

residential-scale electrolyzer systems paired with hydrogen storage and fuel cell technology

While the idea of residential-scale electrolyzer systems paired with hydrogen storage and fuel cell technology is conceptually promising, the market for such integrated systems at the residential level is still in its nascent stages. The primary reasons include high costs, technical challenges, and safety concerns associated with handling and storing hydrogen at home. Most companies currently focus on larger-scale or industrial applications where such challenges can be managed more effectively. However, there are a few companies and initiatives exploring smaller-scale systems that could be suitable for residential use in the future:

1. H2GO Power:
   • As mentioned earlier, H2GO Power is working on safe and efficient hydrogen storage solutions, and while their focus has been broader, the technology has potential applications at smaller scales.
2. Enapter:
   • Enapter is an interesting player in this space; they produce modular electrolyzers intended to be scalable and flexible for various uses, including potentially residential. Their systems are designed to be combined with hydrogen storage and fuel cells, although full integration at the residential level still faces challenges.
3. LAVO:
   • An Australian company, LAVO, has developed a residential hydrogen energy storage system, which includes a hybrid hydrogen battery that integrates an electrolyzer, hydrogen storage unit, and fuel cell. Designed for homes, the LAVO system can store up to 40 kWh of electricity—enough to power an average home for two days.
4. myFC:
   • A Swedish company that focuses on micro fuel cells and hydrogen technology. They have been working on solutions that could eventually be adapted for small-scale residential use.

These companies are pushing the boundaries of what might be possible in the residential sector but are still facing significant hurdles in terms of cost-effectiveness, safety, and infrastructure requirements. As the technology develops and more innovations enter the market, it’s possible we’ll see more viable residential systems in the future. For now, these solutions are more common in commercial or industrial settings or in off-grid applications where traditional power access is limited or non-existent.

 is it competitive towards chemical batteries ? 

Hydrogen energy storage systems, including those like the ones developed by LAVO or Enapter, have unique advantages and challenges compared to more conventional chemical batteries, such as lithium-ion batteries. Whether they are competitive largely depends on the specific applications and priorities of the users. Here's a breakdown of how they compare:

Advantages of Hydrogen Storage Systems

1. Longer Duration Storage: Hydrogen can be stored for long periods without significant losses, making it ideal for seasonal storage, unlike lithium-ion batteries which are better suited for short-term daily cycling.
2. Higher Energy Density: Hydrogen has a higher energy density by weight, allowing for more energy storage in a smaller physical footprint, especially beneficial for applications requiring large amounts of energy.
3. Scalability: Hydrogen systems can be scaled up more easily, which is advantageous for large-scale energy storage or industrial applications.
4. Sustainability: Hydrogen can be produced from renewable sources and is considered a more sustainable long-term solution as it doesn’t rely on metals and materials that may have supply chain and environmental concerns associated with mining and disposal.

Disadvantages of Hydrogen Storage Systems

1. Cost: Currently, hydrogen systems tend to be more expensive both in terms of initial capital outlay and operational costs compared to lithium-ion batteries. This includes costs related to the electrolyzers, storage containers, and fuel cells.
2. Efficiency: Hydrogen energy systems typically have lower round-trip efficiencies. Energy is lost during the electrolysis process to produce hydrogen and again when hydrogen is converted back to electricity via fuel cells. Lithium-ion batteries, by comparison, have higher efficiency rates.
3. Complexity and Safety: Handling hydrogen requires careful management due to its highly flammable nature. This adds to the complexity of installation and maintenance, particularly in residential settings.
4. Infrastructure: Hydrogen fueling infrastructure is less developed compared to the charging infrastructure for battery electric systems. For residential use, this can be a significant barrier.

Market Competitiveness

• For typical residential use, where short-term daily cycling is common and installation space is not excessively constrained, lithium-ion batteries are currently more competitive due to their lower cost, higher efficiency, and simpler usage.
• In scenarios requiring long-term energy storage or where scalability is crucial, hydrogen could be more advantageous. This includes settings like remote locations, critical infrastructure, or where integration with larger renewable installations is necessary.

In conclusion, while hydrogen storage systems offer compelling benefits for certain applications, they are generally not yet as competitive as chemical batteries for standard residential use due to higher costs, complexity, and current technological limitations. However, as technology advances and if priorities shift towards longer storage durations and sustainability, hydrogen could see greater adoption in the future.