Fuel Cells: A Primer for Powering EV Infrastructure

Nashville is on a trajectory to significantly expand its network of electric vehicle (EV) charging stations as part of broader sustainability goals. The city’s rapid growth and commitment to reducing transportation emissions demand reliable, clean power sources for these stations. Among emerging technologies, fuel cells present a compelling option. A fuel cell is an electrochemical device that converts the chemical energy of a fuel—typically hydrogen—directly into electricity, with water and heat as the only byproducts. Unlike internal combustion engines or traditional grid power, fuel cells offer a pathway to zero-emission electricity generation at the point of use.

The fundamental operating principle is the reverse of electrolysis. Hydrogen gas is fed to the anode side of the cell, where a catalyst splits it into protons and electrons. The protons pass through a membrane to the cathode, while the electrons travel through an external circuit, creating an electric current. At the cathode, oxygen from the air combines with the protons and electrons to form water. This clean electrochemical process makes fuel cells an attractive fit for environmentally conscious cities like Nashville.

Why Fuel Cells for EV Charging in Nashville?

The advantages of integrating fuel cells into Nashville’s EV charging infrastructure are rooted in operational, environmental, and grid resilience benefits. These benefits align with the city’s broader climate action plan.

Clean Energy Production

Fuel cells emit only water vapor and heat during operation. This characteristic is especially valuable for urban environments where air quality is a priority. By powering charging stations with fuel cells, Nashville can reduce local air pollutants such as nitrogen oxides and particulate matter associated with conventional power generation. Even when considering the full lifecycle—including hydrogen production—fuel cells can achieve significantly lower carbon intensity than grid electricity from fossil fuels, provided the hydrogen is produced from renewable sources.

High Efficiency and Reliability

Fuel cells convert chemical energy directly to electricity with an efficiency of 40–60%, higher than the typical 30–35% of a combustion-based power plant. In combined heat and power (CHP) configurations, overall efficiency can exceed 85%. For EV charging, this means less energy waste per kilowatt-hour delivered. Additionally, fuel cells operate silently and have few moving parts, resulting in low maintenance and high reliability—critical for a charging network that must be available 24/7.

Energy Storage and Grid Independence

Hydrogen can be stored as a compressed gas or liquid, decoupling energy production from consumption. This storage capability enables fuel cells to power charging stations during peak demand periods or when the grid is under stress. For Nashville, which experiences hot summers and occasional severe storms, distributed fuel cell systems can provide backup power, ensuring that EV charging remains operational during outages—an advantage over purely grid-dependent chargers.

Fast Refueling for Mobility

Although the focus is on stationary charging, the hydrogen supply chain for fuel cells also supports fuel-cell electric vehicles (FCEVs). Refueling a hydrogen vehicle takes less than 5 minutes, comparable to gasoline. While battery-electric vehicles dominate the consumer market, FCEVs remain relevant for heavy-duty applications like trucks and buses. A dual infrastructure—hydrogen for fuel cells powering fast chargers and for FCEV refueling—could create synergies.

Challenges on the Path to Adoption

Despite the promise, several barriers must be addressed before fuel cells become a mainstream solution for Nashville’s EV charging stations. These challenges span economics, infrastructure, and hydrogen sourcing.

High Capital Costs

The upfront cost of a fuel cell system remains high compared to conventional grid-connected chargers or battery storage systems. A typical 100–200 kW fuel cell stack can cost $500–$1,000 per kW installed. For a fast-charging station requiring multiple units, the total investment can be prohibitive. However, costs have been declining over the past decade—through advances in manufacturing, catalyst reduction, and economies of scale—and are projected to continue falling. Nashville could leverage federal grants and state incentives to defray initial expenses.

Limited Hydrogen Infrastructure

Building a hydrogen supply chain—production, compression, storage, and distribution—is a massive undertaking. Nashville currently has no public hydrogen refueling stations, and industrial hydrogen is typically produced via steam methane reforming (SMR) using natural gas, which emits CO₂. For fuel cells to deliver their full environmental benefit, hydrogen must be produced from low-carbon or renewable sources. Developing a local hydrogen hub would require investment in electrolyzers powered by solar or wind, along with pipeline or trucking logistics. Without a “chicken-and-egg” solution, early adopters face chicken-and-egg delays.

Sustainable Hydrogen Production

The most common production method today—SMR—generates 9–12 kg CO₂ per kg hydrogen. To align with Nashville’s climate goals, hydrogen must shift toward “green hydrogen” produced via electrolysis using renewable electricity, or via SMR with carbon capture (blue hydrogen). The cost of green hydrogen is currently $4–$7 per kg, compared to $1–$2 for gray hydrogen (SMR without capture). As renewable energy prices fall and electrolyzer efficiency improves, green hydrogen is expected to become cost-competitive within the next decade. Meanwhile, Nashville’s growing solar and wind resources can supply clean electricity for electrolysis, positioning the city as a sustainability leader.

Fuel Cell Technologies: Which Type Fits Nashville?

Not all fuel cells are alike. Several types exist, each with distinct characteristics suited to different applications. For stationary EV charging, two types stand out:

Proton Exchange Membrane Fuel Cells (PEMFC)

PEMFCs operate at relatively low temperatures (60–80°C), have high power density, and can ramp up and down quickly. They are the dominant technology for both fuel cell vehicles and small stationary power. PEMFCs are well-suited for distributed charging stations, as they can be packaged in compact units with fast startup. However, they require high-purity hydrogen, and the platinum catalyst adds cost. Ongoing research to reduce platinum loading or use alternative catalysts could lower costs further.

Solid Oxide Fuel Cells (SOFC)

SOFCs operate at high temperatures (600–1,000°C) and can run on various fuels, including natural gas, biogas, or hydrogen. They are more efficient than PEMFCs and do not require high-purity hydrogen; internal reforming can process methane. SOFCs are better suited for larger installations where heat can be captured for CHP applications—such as at a bus depot or fleet facility with on-site energy needs. Their high temperature means slower startup and less ability to follow load fluctuations, but for continuous baseload power, they are excellent. Given Nashville’s growing transit electrification, SOFC-powered charging hubs could be a prime candidate.

Comparing Fuel Cell Charging with Battery Storage

A natural question is why not simply use battery energy storage systems (BESS) to buffer grid power for EV charging. Both approaches can provide grid resilience and peak shaving. The choice depends on duration, cost, and operational requirements.

  • Duration: BESS is ideal for short-duration (1–4 hours) energy storage, while hydrogen storage can hold energy for days or weeks. For Nashville’s seasonal variations—e.g., longer winter nights with lower solar production—hydrogen offers a longer-duration solution.
  • Round-trip efficiency: Batteries achieve 85–95% round-trip efficiency; hydrogen with fuel cells is 30–40% (power-to-hydrogen-to-power). This lower efficiency means more renewable energy is needed per unit of electricity delivered. However, if hydrogen is produced from surplus renewable energy that would otherwise be curtailed, the system can still be economical.
  • Scalability: Hydrogen storage is more easily scaled up (by adding more tanks) without the cost penalties that come with scaling battery systems. A station requiring many megawatt-hours of backup could be cheaper to serve with hydrogen.
  • Lifecycle and environmental impact: Batteries rely on lithium, cobalt, and other mined materials with significant environmental and social footprints. Fuel cell stacks use more abundant materials, though platinum remains an issue. A comprehensive life-cycle assessment should consider both.

In practice, a hybrid approach—combining fuel cells with batteries—can leverage the strengths of both: batteries handle short-term surges and fast charging demands, while fuel cells provide sustained, long-duration power and backup. Several pilot projects, such as those in California and Japan, have demonstrated this hybrid model.

Policy and Regulatory Landscape in Tennessee

The adoption of fuel cell technology in Nashville is shaped by state and federal policies. Tennessee does not currently have a hydrogen roadmap, but recent federal initiatives provide momentum. The U.S. Department of Energy’s Hydrogen Shot aims to reduce the cost of clean hydrogen to $1 per kilogram by 2031. The Infrastructure Investment and Jobs Act (IIJA) and Inflation Reduction Act (IRA) include significant tax credits for clean hydrogen production (Section 45V) and investments in hydrogen hubs. The Southeast Hydrogen Hub, which includes Tennessee, is one of the regional hubs funded by DOE—Nashville could benefit from this initiative.

Local utility policies also play a role. The Nashville Electric Service (NES) governs grid interconnection and tariffs. Fuel cell systems that export power to the grid would need net metering or feed-in tariff arrangements. Additionally, building codes and zoning regulations should be updated to accommodate hydrogen storage and dispensing. Engaging with these regulatory bodies early can smooth deployment.

Case Studies and Lessons Learned

Several municipalities and companies have already deployed fuel cells for EV charging. Their experiences offer insights for Nashville.

California’s First Fuel-Cell-Powered Fast Charger

In 2020, the California Energy Commission funded a project by Toyota and FuelCell Energy to install a 250-kW fuel cell system at a truck stop near the Port of Long Beach. The system provides fast charging for heavy-duty electric trucks, demonstrating that fuel cells can handle the high power demands of commercial fleet charging. The project showed that a dedicated hydrogen supply—in this case, delivered by trucks—can bypass the need for a hydrogen pipeline. For Nashville, trucked-in hydrogen could be a practical initial step.

Japan’s Hydrogen Station Network

Japan has built a network of hydrogen stations that include both vehicle refueling and stationary power for surrounding facilities. Some stations use fuel cells to supply backup power to the station itself and export excess electricity to the grid. This model of “hydrogen station + fuel cell” could be replicated at high-traffic EV charging locations in Nashville, providing dual services.

H2@Scale at the National Renewable Energy Laboratory (NREL)

NREL’s H2@Scale project in Colorado explores integrating hydrogen production, storage, and fuel cells with renewables. The system uses electrolyzers to produce hydrogen from surplus solar and wind, then uses fuel cells to generate electricity when needed. The scalability and real-world data from this project demonstrate the technical feasibility of such systems. Nashville’s varying renewable resources could benefit from a similar integrated approach.

Implementation Roadmap for Nashville

Moving from concept to reality requires a phased approach. Below is a suggested roadmap for deploying fuel cell-powered EV charging in Nashville:

Phase 1: Pilot Projects (2025–2026)

Identify 2–3 strategic locations—such as a fleet depot (Metro bus yard or delivery hub), a high-profile public charging station near downtown, and a remote park-and-ride lot with weak grid connection. Install small-scale PEMFC systems (50–100 kW) paired with battery buffers. Source hydrogen initially from trucked-in supplies from nearby producers (e.g., Air Liquide’s existing plant in the region). Monitor performance, costs, and reliability. This phase should be funded through DOE grants (DOE Fuel Cell Projects) and state clean energy funds.

Phase 2: Infrastructure Scaling (2027–2029)

Based on pilot data, expand to 10–15 stations strategically placed along major corridors (Interstates 40, 24, 65). Install larger SOFC systems at marquee locations with CHP capability. Develop a local hydrogen production facility using electrolysis powered by Nashville’s solar array projects (e.g., the city’s commitment to 100% renewable energy for municipal operations). Partner with regional stakeholders like the Tennessee Valley Authority (TVA) to explore hydrogen blending in natural gas pipelines.

Phase 3: Integration and Grid Services (2030+)

At full scale, the fuel cell fleet can provide grid services such as demand response, frequency regulation, and capacity relief. Aggregated fuel cell systems could be dispatched by NES to reduce peak load. Nashville could become a model for how distributed fuel cell charging stations support a resilient, clean grid. The Hydrogen Shot cost targets should be met by then, making green hydrogen economically viable.

Environmental and Economic Impact Metrics

To justify investment, Nashville must track key performance indicators:

  • Carbon reduction: tons of CO₂ avoided compared to grid-powered charging (assuming a mix of natural gas and renewables). Fuel cell charging using green hydrogen can achieve near-zero emissions at the site.
  • Air quality improvement: reduction in NOx and PM2.5, measured via local monitoring stations near charging hubs.
  • Cost per charged mile: total cost of ownership (fuel cell equipment, hydrogen, maintenance) divided by miles driven by EVs using the charging network. Target: parity with grid-only cost by 2029.
  • Resilience benefit: avoided downtime costs during grid outages, measured by the number of hours charging stations that remained operational during events.
  • Job creation: direct jobs in hydrogen production, fuel cell manufacturing, installation, and maintenance in the Nashville region.

Strategic Partnerships and Funding

No city builds advanced infrastructure alone. Nashville should actively pursue partnerships with:

  • Fuel cell manufacturers: companies like Plug Power, Ballard Power Systems, or Doosan Fuel Cell supply modular units suitable for charging.
  • Hydrogen producers and suppliers: Air Liquide, Linde, or regional electrolyzer firms can provide hydrogen production and logistics.
  • Automakers and fleet operators: collaborations with Ford, GM, and local delivery companies (e.g., FedEx, UPS) to test fuel cell-powered charging for commercial fleets.
  • Research institutions: Vanderbilt University, Tennessee State University, and Oak Ridge National Laboratory can conduct R&D and workforce training.
  • Federal and state agencies: actively apply for funding from DOE (Fuel Cell Technologies Office), USDOT, and the Tennessee Department of Environment and Conservation.

The Road Ahead

The vision of fuel cells powering Nashville’s EV charging stations is grounded in both technological reality and policy momentum. The challenges—cost, infrastructure, hydrogen production—are significant but surmountable. By learning from early adopters and leveraging federal support, Nashville can position itself at the forefront of clean energy transportation. A strategic, phased rollout will generate the data and confidence needed to scale. The city’s commitment to sustainability and its economic growth provide a fertile environment for innovation.

Fuel cells alone won’t solve every challenge, but as part of a diversified clean energy portfolio—alongside solar, wind, battery storage, and smart grid management—they offer a unique value proposition: clean, reliable, and resilient power for the electric vehicles that will define Nashville’s future mobility. The time to start piloting is now.