Hawaii Energy and Environmental Technologies (HEET) Initiative Office of Naval Research Grant Award Number N0014-11-1-0391 Task 7. HYDROGEN SYSTEMS 7.2 Island of Hawaii Integrated Hydrogen Systems Prepared by: University of Hawaii at Manoa, Hawaii Natural Energy Institute September 2016
Island of Hawaii Integrated Hydrogen Systems HNEI is supporting a project on the Island of Hawaii to deploy and operate two hydrogen fuel cell shuttle buses at Hawaii Volcanoes National Park (HAVO) located in a high air contaminant environment that may be similar to those found on the battlefield and could seriously degrade the fuel cell power systems. The buses will be used to test a novel (patent pending) air filtration system developed by HNEI to protect the shuttle bus PEM fuel cell power systems from airborne contaminants. Hydrogen will be delivered from the Natural Energy Laboratory Hawaii Authority (NELHA) located on the West side of the Island of Hawaii to HAVO using hydrogen transport trailers as illustrated in Figures 7.2.1 and 7.2.2. In anticipation of operating the buses at HAVO, HEET 10 funding was used to support the design and procurement the HAVO hydrogen dispensing systems. This subtask supported the following objectives: Support the operation of the HAVO buses by supplying the hydrogen dispenser system; Develop and supply a hydrogen dispenser boost pump system to reduce hydrogen transport costs. ONR had originally requested HNEI evaluate the performance of stationary PEM fuel cell power systems at high altitudes by installing stationary fuel cell power systems at the Pohakuloa Training Area (PTA) and the Mauna Loa Observatory (MLO). Schedule delays have precluded the project s ability to install and operate the PTO and MLO fuel cell systems under HEET 10. 1
Figure 7.2.1: Hydrogen Delivery Concept Figure 7.2.2: Hydrogen Transport Trailer HAVO Hydrogen Dispensing System HNEI designed the 350 bar HAVO hydrogen dispensing station illustrated in Figure 7.2.3. The main components are comprised of Drag & Drop hydrogen transport trailers that are hauled by truck from NELHA to HAVO. The trailers are connected to a fueling dispenser via a fueling 2
post that acts as an interface between the trailer and the dispenser. Each trailer is filled with 105 kilograms of hydrogen at a pressure of 450 bar. A full trailer is transported to the site from NELHA and an empty trailer is picked up and returned to NELHA to be refilled. The station employs a cascade fill process that leverages the energy expended to fill the trailer with 450 bar hydrogen at the NELHA site. The trailers are connected to a computer-controlled dispenser that controls air-operated valves on the trailers to automatically fill the bus to a pressure of 350 bar. Figure 7.2.3: HAVO Hydrogen Dispensing Station The station is unattended and is monitored remotely over the Internet. automatically shut down if there is a problem or a loss of communications. The station will Hydrogen Dispenser Utilizing HEET 10 funds, HNEI contracted Powertech for the supply of a 350 bar automated dispenser illustrated in Figure 7.2.4 for the HAVO site. 3
Figure 7.2.4: HAVO Dispenser The dispenser has all the necessary controls, sensors, and data acquisition system to monitor performance and ensure safe operation. An interface to allow remote monitoring of operations via the internet is provided. Due to the high storage pressure of the hydrogen trailer, a relatively fast fill can be achieved allowing a bus to be filled at any time of day. Hydrogen Dispenser Boost Pump System Utilizing HEET 10 funds, HNEI contracted Powertech for the design and supply of a hydrogen boost pump system that is integrated into the HAVO hydrogen dispenser. The round trip distance to supply hydrogen from NELHA to HAVO is 300 miles. This incurs a considerable transportation cost. It was calculated that using the cascade fill methodology, the trailer would be 61.5% full when unable to complete a fill to >95% SOC (state of charge) at which time it needs to be returned to NELHA for refilling. In order to extract more hydrogen from the trailer, it was decided to add a boost pump system to the HAVO dispensing system. A booster pump system was designed with the following capabilities and features: Capable of compressing from low-pressure storage banks to high-pressure storage banks in the tube trailer. This increases the number of cascade fills that can be performed per trailer. Compressing directly to the vehicle tank via the dispenser if unable to perform a cascade 4
fill. Doubling the number of fills per trailer that can be completed to 95% SOC compared to the original design (based on simulations using a bus with a 10 kg hydrogen tank of 5,000 psi normal operating pressure). Simulations were conducted to determine the performance of the booster pump upgrade. The results of these simulations were: 8 fills to >95% SOC can be completed per trailer o Approximately 4 fills to >95% SOC can be completed without the booster pump upgrade Fills #1 to #4 are fast cascade fills. Fill #5 is a slower cascade fill. The final 3 fills (#6 to #8) will require direct compression into the bus via the dispenser after a mini cascade fill. o These fills will be slower (ranging from 1 to 6 hours). The compressor will take an average of 9 hours and a maximum of 15 hours between fills to restore storage to its maximum fueling power (cascade fill). The trailer will be approximately 23.5% full after 8 fills. A 9th fill can be completed with direct compression and a mini cascade fill to 93% SOC over an extended period of time o The trailer will be approximately 10.3% full after this final fill Assumptions Vehicles (buses) maximum tank size is 10 kg of hydrogen at 5,000 psi and 15 C as provided; Vehicles arrive with 0 kg of hydrogen in the tank and are filled to at least 9.5 kg (95%<SOC<100%). Only applicable in fills #1 to #8; Adequate recovery time is provided between each fill; Hydrogen supply (tube trailer) arrives on-site with a minimum of 6,000 psi hydrogen at 15 C (99.74 kg hydrogen); Compressor (booster pump) outlet pressure of 6,000 psi at 15 C (maximum outlet pressure); and Compressor runs continuously at the flow-rate specified by the manufacturer. The dispenser and boost pump systems have been completed and are ready for installation at the HAVO site. 5
Publications / Presentations 1. Ewan M., Rocheleau, R., Oral presentation at US DOE Annual Merit Review, Hydrogen Energy Systems as a Grid Management Tool, Washington, DC, June 9, 2016. 2. Ewan M., Oral presentation at US DOE Sustainable Transportation Summit, H2@Scale Stakeholder Panel Session, Washington, DC, July 12, 2016. 6