View the Schatz Solar Hydrogen Project operating in real time »
Elementary school students play "the hydrogen game" at the Schatz Solar Hydrogen Project in Trinidad, CA.
The Schatz Solar Hydrogen Project is a full-time, automated, stand-alone energy system that demonstrates that hydrogen can be used to store solar energy. It powers the air compressor that aerates the aquaria at Humboldt State University's Telonicher Marine Laboratory in Trinidad, California. The system uses energy from the sun to power the compressor directly and to produce hydrogen that powers the compressor when the sun is not available. The end result is that the fish enjoy solar-powered air bubbles twenty-four hours a day.
In the solar hydrogen cycle, solar energy provides the electricity to remove hydrogen from ordinary water by the process of electrolysis. The hydrogen can then be stored or transported. When hydrogen is recombined with oxygen, usable energy results. No resources are consumed and the only byproduct is pure water. In this cycle hydrogen is an energy carrier; it allows us to store and transport solar energy in large quantities.
New interpretive signs are posted and a detailed brochure (view PDF version) is also available to explain the system to visitors.
Sunlight hits the photovoltaic panels, which convert solar energy into electricity. This electricity is used to first power the air compressor directly. When more energy is available than the compressor needs, the excess electricity powers an electrolyzer, which splits water into oxygen and hydrogen. The oxygen gas is vented to the atmosphere, and the hydrogen gas is stored in tanks behind the lab.
When the photovoltaic panels do not receive enough sunlight to power the compressor (either at night or when the weather is cloudy), the system automatically shifts to fuel cell operation. The fuel cell directly converts chemical energy into electricity by combining the stored hydrogen with oxygen from the air—basically the reverse of the electrolyzer. In this way water and sunlight, both natural and abundant, are used in a cycle to produce power. Hydrogen stores solar energy, so the power is available whenever it is needed.
Learn more about how fuel cells work »
The system has been in operation since 1991. A complete retrofit of the computer control systems took place in 2001-2002. The ten-year-old photovoltaic modules were also tested for degradation during this time, and the results were presented at the 29th IEEE PV Specialists conference in May 2002 (see (PDF) "Effects of Mismatch Losses in Photovoltaic Arrays”).
To increase system performance, overall efficiency, and make the system run almost like new, SERC replaced the fuel cell stack, installed state-of-the-art maximum power point trackers, rewired the PV array from 24 Volts nominal to 48 Volts nominal to reduce power loss in the wiring, and installed DC-to-DC converters to maximize electricity and hydrogen production. Read our newsletter article "Renewables Renewed," (PDF) for additional information on the rebuild.
Visitors are welcome at the Schatz Solar Hydrogen Project. The project is not normally staffed, but you can visit the site during the Marine Lab’s open hours. For hours and directions, see www.humboldt.edu/~marinelb/visitor.html or call (707) 826-3671. Interpretive signs and a detailed brochure (PDF) available at the Marine Lab explain the Schatz Solar Hydrogen Project to visitors.
