Some of the largest coal reserves in the world reside in the North Central region of the United States. And some of the strongest and most sustained winds reside there as well. And although wind energy is plentiful in the West, it is often not available when needed. But merely building more coal-burning facilities is no longer an option as utilities respond to pressures to reduce carbon emissions. So, perhaps we should marry coal and wind. But before we tie the knot, let's add a little twist.

Coal Gasification

We've seen giant technology strides in effectively extracting synthetic gas (syngas) from coal and tar sands over the past few decades. So, here is my thinking. Let's use syngas to back up wind. This will enable us to provide energy when consumers need it, while driving down the overall levels of CO₂ released to the atmosphere. Gas-fired turbines can be ramped up and down relatively easily, and they also generate less CO₂ than coal. Coal produces around 210 lbs of CO₂ per million Btu, whereas syngas and liquid fuels might produce half that.

Back in 2000, I referenced work by Prof. Ron Spahr at the University of Wyoming when he performed a feasibility study of building a 2000-MW dc line to export power from mine-mouth coal-fired plants located in the Powder River Basin to load centers in the western, midwestern and southern United States. Since that time, the need for bulk transmission has only increased as major wind farms are sited in the northern plains.

I recently got wind (pun intended) that Spahr, a degreed engineer, had moved to the University of Memphis where he serves as professor and chair in the finance department. I tracked down Spahr, who has quite a pedigree in the coal-conversion scene, having consulted for the likes of Amoco, Siemens, Black & Veatch, NIKoil and Siemens AG.

Spahr has invested quite a bit of intellectual capital into the business case for the conversion of Wyoming and Montana coal into syngas. At the same time, he has been evaluating technology that would enable us to capture and sequester CO₂ during the conversion process. Spahr finds it is much cheaper to capture CO₂ while gassifying coal than collecting it in the stacks from coal-fired plants. Spar says there are quite a number of sites with water and railroad access where conversion facilities can be located in the Powder River Basin.

Spahr believes an integrated gasification combined cycle (IGCC) facility could thus provide power to the electrical grid to firm up wind generation. He tells me we could also site technology that would enable us to convert this same syngas to liquid fuels including gasoline, diesel and jet fuel for the transportation industry.

Spahr has run calculations to show that production costs for both electrical power and synthetic fuels are within current price ranges for electricity and liquid fuels, with electricity generated at a fully recovered levelized cost in the US$60 to $70 per MWH range and liquid fuels produced at a fully recovered levelized cost in the $60 range for synthetic gasoline and $76 range for diesel or jet fuel.

Backing Up Wind

As for the need to back up wind, there is no doubt. I traveled with members of the Solar Electric Power Association to Spain last year to see how that country was handling its 9 GW of grid-connected wind. The folks at utility Iberdrola told us they routinely back up their wind with gas-fired generation. The same need for gas-fired backup is holding true for wind being shipped into Dallas and Houston from the wind zones in northwest Texas.

Today, natural gas is plentiful, so you might suggest we just sit on our 350-year supply of coal. But we've experienced so many gas price spikes and plunges over the years, we know we can't rely solely on natural gas. And leaving energy up to the free market has proven to be quite painful to consumers, not to mention the economy. Most people, myself included, believe we need a national, integrated energy strategy.

Spahr concurs and suggests we move forward on coal gasification with a federal government sponsored enterprise (GSE). Because of the high up-front costs and the truly national scope and impact of coal-to-syngas and coal-to-liquid initiatives, Spar suggests that we launch, finance and construct major facilities with federal government backing and funding.

Clearly, we need a national energy policy that balances costs with rewards. If Spahr's vision catches on, we won't have to take our lumps with coal — not when we can convert our coal to syngas and back up green with gas.

Editor's note: Dr. Ronald W. Spahr can be reached at rspahr@memphis.edu.