Integrating renewable energy - May 08, 2011 - Phil Carson - - Future Fuels - Generation - Technical Articles - Index - Library - GENI - Global Energy Network Institute

Integrating renewable energy

May 08, 2011 - Phil Carson -

An effort to convert renewable energy resources (wind- and solar-generated electricity) into a storable, transportable medium (hydrogen gas) is alive and well in the foothills of the Rocky Mountains.

Why does that matter today?

If you're paying attention to our national budget debate, this is a particularly poignant moment in which to illustrate how a sliver of your federal tax dollars are used to fuel economic growth, raise our standard of living and, in the process, increase our energy and, therefore, national security.

It's an opportunity to point out that, despite how attractive the so-called "free market" looks on paper, the "real market" often requires partnerships between private industry and government-funded and conducted research—research that is held to a rigorous standard goal of commercialization by job-creating, economy-stimulating private, free-market interests.

And it underscores my perennial point that a diverse portfolio of options—"the mix"—is always preferable to putting all your marbles in one basket.

None of this need be political. It is simple common sense. 

To wit: Yesterday morning I traveled up the Front Range here to the U.S. Department of Energy's National Renewable Energy Laboratory's (NREL) Distributed Energy Resources Testing Facility (DERTF). Kevin Harrison, senior engineer at the Electricity, Resources, & Building Systems Integration Center, is focused on optimizing the conversion of wind turbine- and solar photovoltaic-generated electricity to hydrogen.

Briefly, the process: Either a PV array or a wind turbine generates electricity and that electricity passes through a converter (variable AC-to-DC or DC-to-DC) to an electrolyzer, which generates hydrogen gas. That gas goes to a compressor to storage under high pressure.

The notion is that pressurized hydrogen can be stored for on-site use or transported and dispensed for a variety of purposes. Hydrogen can power fuel cells in vehicles. It can power a generator, providing electricity for local uses or the grid. Hydrogen can be used for industrial processes, such as oil refining.