Global electricity demand is projected to grow substantially, with the economies of India and China seeing the greatest increases. Many factors come into play, including the proliferation of electric vehicles, data center expansions driven by artificial intelligence, the conversion to highly efficient heat pumps for heating, and the overall transition to decarbonize.
At the same time, powerful weather events have increased due to the impact of warming oceans, rising sea levels, and shifting storm patterns associated with climate change. The number of storms spiked 21% in the last 50 years, according to NASA. More striking, the occurrence of violent category 4 or 5 hurricanes has nearly doubled in the same timeframe.
This comes at a time when the aging electrical infrastructure of transmission and distribution lines needs to be expanded and upgraded. Maintenance of these lines must increase as weather-related events contribute to 83% of major outages. All of these factors combine to create a fragile grid and an unreliable supply of cost-effective power, at a time when the appetite for electricity is on the rise.
Global utility adaptations: Globally, utility companies are taking steps to keep pace with the changing landscape by diversifying energy production, including renewables, hydroelectric, nuclear, and natural gas. Deploying energy storage with batteries to complement solar and wind production is now common. Implementing smart grid technology leveraging AI to more effectively match production with consumption has begun.
Governments are investing heavily in transmission projects. The Changji-Guquan high-voltage DC network in China will connect the Changji region with Guquan, 3,200 kilometers away. In the United States, the Bipartisan Infrastructure Law and the Inflation Reduction Act allocated $30 billion to expand transmission capacity and link regions in North America.
All of these initiatives are noble but only address production, transmission, and distribution. They do not adequately diversify the grid at the point of energy consumption.
Enhancing end-user resilience: Enhancing backup at the end-user location and proliferating microgrids adds a level of redundancy and resilience missing today. Sourcing power closer to the end user mitigates transmission and distribution restraints and creates the opportunity for ‘islanding’ or disconnecting from the grid altogether. This is where hydrogen fits into the puzzle.
Hydrogen fuel cells are utilized for emergency power for both small-scale and large-scale applications. Small-scale stationary power fuel cell sites, generally less than 100 kW, offer longer run times than batteries alone and require less frequent refueling than traditional generators. Sustainability and a desire to reduce emissions drive much of the interest. However, economic and operational benefits play into the decision.
Hydrogen backup in telecom infrastructure: One prominent use case for hydrogen as a backup source can be found at wireless towers. These small-scale sites are a strong fit because of the longer run time than batteries alone and elimination of fossil fuels. Fuel cell use is growing at wireless sites throughout Asia, and SFC Energy is deploying stationary power fuel cells for auxiliary power in public safety communication networks in Europe. However, the largest deployment of fuel cells in wireless communication networks is in the United States at Southern Company.
Southern Company deployed hydrogen fuel cells at over 500 wireless towers across the Southeastern United States to extend service in the case of a power outage. The fuel cell extended the run time to three to five days, compared to four to eight hours for batteries alone. The longer reserve time proved critical to the operations of the network as this area is prone to hurricanes and other weather-related extended power outages.
The business case for fuel cells resulted in a lower total cost of ownership in part because of the smaller space required. The site footprint consists of an equipment cabinet that houses the electronics, fuel cell, and small battery string. The second cabinet holds high-pressure cylinders of hydrogen. Refueling of the hydrogen cabinet is done with a portable hydrogen trailer. Southern Company eliminated a generator from the architecture, which drastically reduced both the capital cost and the real estate allocated at each site. The network of fuel cells has operated in the fi eld for close to ten years with a strong track record of performance.
Large-scale backup power with hydrogen fuel cells: Although early in development, large-scale hydrogen fuel cell backup power is gaining interest, particularly in the data center market. Cloud computing firm Equinix has begun evaluating hydrogen in its global network, piloting fuel cells at sites in Dublin and Singapore as part of a demonstration program to use hydrogen for emergency power. The company hopes to confirm the viability of hydrogen as a replacement for diesel gensets, with the potential to expand to other sites if successful.
In one of the most visible hydrogen fuel cell programs in the data center industry, Microsoft partnered with Plug Power on a 3-MW fuel cell, large enough to replace a traditional generator.
Microsoft aims to be carbon-negative by 2030, and data center emissions present a significant hurdle in reaching that objective. The project is the result of years of research into clean power, and the 3-MW threshold was a cause for celebration after the completion of successful testing.
In the words of Sean James, Microsoft’s Director of Data Center Research, “What we just witnessed was, for the data center industry, a moon landing moment. We have a generator that produces no emissions. It’s mind-blowing.”
Well-founded concerns remain about how to supply hydrogen at levels required to replace diesel generators at data centers. How hydrogen will continue to expand into the market is yet to be seen, but progress so far has been encouraging.
Supporting microgrids with hydrogen: Microgrids may hold the most promising application for hydrogen in supporting the health of the power grid. After the deadly California wildfires, Pacific Gas & Electric (PG&E), the local utility, looked for ways to provide reliable power to essential services during Public Safety Power Shutoffs and natural disasters. The City of Calistoga selected a hybrid of batteries and hydrogen fuel cells for auxiliary power for its microgrid. The combination provides up to 48 hours of power for critical facilities like fi re and police stations, as well as the region’s 2,000 customers, and will be the largest long-duration energy storage system in the United States.
The project by Energy Vault, called the Calistoga Resiliency Center, uses green hydrogen and provides 100% clean energy. The stationary power PEM fuel cells replace the seasonal diesel generators used in the past. The hydrogen, stored as a liquid for higher energy density, can be refilled as needed for extended outages.
The concept is simple. During a Public Safety Power Shutoff or other long-term service interruptions, the region will disconnect from the PG&E grid. The Energy Vault system will come online and provide the necessary power until the event passes. This ‘islanding’ allows residents and businesses to continue operating completely independently of the larger grid. Islanding can also prevent cascading failures and avert blackouts from spreading to other regions in California.
With this technology, Calistoga residents can continue their lives without relying on diesel generators for emergency power. Silent, clean, and reliable hydrogen power replaces the noise, NOx emissions, and general inconvenience of fossil-fueled backup systems.
Activity with microgrids is not limited to the United States. Australia has a cutting-edge pilot for microgrid robustness. In Denham, Western Australia, Horizon Power is using a hybrid of renewable energy and storage systems to support its microgrid. Hydrogen is not solely used as backup power but also as primary power to complement the BESS (battery energy storage system).
Hydrogen will be produced from excess renewable energy from solar and wind sites that already support the region. At night or during low renewable output, the hydrogen fuel cell will produce electricity to augment the battery system, broadening the reach of renewable energy and reducing diesel reliance. The hybrid system adds resilience and redundancy to the microgrid while reducing NOx and CO2 emissions, resulting in cleaner air and stable power for the Outback.
Hydrogen’s role in a resilient energy grid: There is no single solution to stabilizing the electrical grid. Numerous improvements must be made to meet growing demand while minimizing environmental and economic impacts. Hydrogen offers a promising means to ensure reliable, cost-effective power on demand, but it must be strategically integrated into the broader energy landscape.
This article appeared in the December issue of Hydrogen Tech World.
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