Texas is extraordinarily well-positioned with respect to two of the most talked-about ways of reducing carbon emissions to the atmosphere: wind generation and carbon capture and storage.
When I moved here, one of the most striking things I noticed about the night sky was the speed of the clouds blown about by the nighttime winds. It’s breathtaking, and it’s helped make Texas the site of more wind-generating capacity than any other state in the country by a large margin. You’ve probably seen either turbines or pictures of them. They’re about the size of the UT Tower. I was delighted on a flight to San Francisco last week when my flight attendant announced that out the window, we could see not the Grand Canyon, but the West Texas wind farms. The machines are beautifully engineered to capture the wind.
What we cannot yet do is store the electricity that we make by capturing the wind on a large scale. And that’s why the point about the high nighttime wind speeds is important — people don’t really use that much electricity at night, and we have coal and nuclear power plants that are hard to turn on and off supplying the nighttime electricity we do use. If we could generate lots of wind electricity at night and save it to use the next day, that would be fine, but as the technology currently stands, we have to generate power that matches the amount of power being used.
This inability to store a desirable resource contrasts with the carbon situation, where oil field engineers and geologists have devised ways of keeping carbon dioxide trapped in spaces deep below the surface. Questions remain about the permanence of storage over geologic time, but many agree that deep geological storage is technically feasible.
To store the carbon, however, we must first capture it, and that’s been a bit of a problem. Mostly because it takes a lot of energy to separate carbon dioxide from other gases, which means we need to generate more energy, which right now means we need to emit and capture additional carbon and extract additional carbon-based fuels. What this means is that a coal-fired power plant that is sequestering most of its emitted carbon uses about 30 percent more coal than a conventional plant does, which represents 30 percent more mining and 30 percent more pollutant volume — CO2 and otherwise.
Texas can take advantage of the need to strip CO2 out of natural gas and the relatively pure CO2 streams produced by refineries because of the state’s large conventional energy sector. In these cases, the CO2 is being captured anyway, so it’s not an additional burden on fuel use to get at it. Storage requires relatively little (though not insignificant) amounts of energy, so it may make sense to store these already nearly pure streams of CO2 away from the atmosphere. Moving to large scale capture from exhaust gases at power plants, however, represents a serious energy investment.
So we can capture the wind and store the carbon, and there’s a lot of effort being expended on figuring out how to store the wind and capture the carbon. My personal preference is that we spend a lot more time working on storing wind than capturing carbon, mostly because of the magnitude of the non-climate impacts associated with additional use of carbon-based fuels.
Wind power generation doesn’t require water during operation, while coal-fired generation requires significant amounts for cooling — and more when carbon capture systems are brought into the equation. Not only are those direct water uses impactful, but mining coal can have major effects on ground and surface water quality near mines, and the land-use problems associated with mining are very substantial.
There are some measures that we can take to protect the climate that fundamentally enhance sustainability, while others are taken only because they keep greenhouse gases out of the atmosphere. To me, wind generation and deployment of efficiency and conservation measures promote long-term goals of cleaner air, lower reliance on exhaustible resources and opportunities for saving money. Carbon capture and storage is admittedly pretty cool technology, but it does little to promote goals other than preventing carbon emissions. Power generation infrastructure has very long lifetimes, and so committing to a future based on carbon capture is committing to a future that delays the eventual need to use renewable resources.
The fact is, the wind doesn’t always blow. But when it does, we know how to capture it. So let’s put more effort into figuring out how to work with that rather than relying on exhaustible resources that put major pressure on land, water and community systems.
Grubert is an energy and earth resources graduate student.
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