The best way to store the wind-generated power is anyone’s guess. The equipment for one idea comes from Toronto-based Hydrogenics, a firm that manufacturers industrial electrolysis units, devices that separate hydrogen from oxygen in water. Hydrogen can be used in industrial applications, but the company suggests storing it as a vehicle fuel and provides several examples of city busses that could use it as well.

Hydrogenics’ HyStat 60 consumes about 365 kWh to product 60 m3/h of hydrogen. Storage and dispensers are not shown.

That’s not all, says Robert McGillivray, the company’s director of renewable energy. “Electrolyzers operate over a wide range of capacities from 10% to 100% of rated load for large, multi-stack systems. And they can quickly ramp up and down without adverse effects. That means the units could come on and off line quickly to provide load to the grid when necessary and drop off when daily demand grows as it does around sunrise.”

With storage, as would be needed for fueling stations, electrolysis can operate at times that vehicles don’t need fueling. The vehicles could be cars but more likely they would be city busses powered by fuel cells. (GM and others have announced that 2015 could be the year that fuel cell powered cars go on sale. The company also recently showed off its Gen2 fuel cell.) The interest from this magazine is that the electrolyzers could be powered by wind energy.

McGillivray says the company’s HySTAT line of electrolysis units is modular with building blocks of 365 kW capable of generating 60 m3 of hydrogen per hour. Multiple systems could work at a site to consume 1 to 5 MW. Larger systems could consume 10 to 100 MW. The hydrogen generator is containerized and available with a compression, storage, and dispensing package to match the needs of the vehicle fleet. The idea is that hydrogen would be produced when needed and on site rather than pumped from miles away.

McGillivray says there are over 150 fueling stations around the world supporting demonstration programs for buses, cars, and vehicles such as forklifts. A fleet of 100 municipal buses would consume about 3.8 tones of H2/day given typical bus routes. If supplied by electrolysis, this would represent about 10 MW of continuous load.

The company has provided electrolysis equipment for over 35 fueling stations worldwide including one program in Europe and stations in California supporting bus and car fleets. Fueling stations and their load could be in several locations allowing control of the grid to address transmission constraints as well as load balancing. WPE