A brown lump of lignite coal is dug up from an exposed open pit, placed on a conveyor belt in a power plant, and sent to contribute toward the generation of electricity for households across the state. Such is the scene, not deep in the heart of the Lone Star State, in one of its more remotely populated counties, but rather, 30 minutes outside the state’s capital and fourth most populated city, Austin.
This strip mine, or surface mine, is one of many in Texas, contributing to its status as the country’s leader in production of lignite coal. According to the American Society for Testing and Materials, there are four grades of coal, with anthracite being the highest ranked in energy per pound, and lignite, the only type mined in Texas, being the worst in terms of energy efficiency per pound burned. Lignite’s infamous distinction is a result of its high moisture content and low energy density.
Furthermore, beyond being a leader in lignite production, Texas is also the leading state with regard to coal consumption, having the highest emissions of carbon dioxide and sulfur dioxide in the country, according to an analysis by the U.S. Energy Information Administration. Apart from coal, Texas is also the leading producer of oil, providing for more than 33% of the United States’ crude oil needs.
These distinctions, however, do not come as a surprise, since the image of Texas on the national stage as a behemoth in the oil and coal industry is well established. What does come as a surprise is the Lone Star State’s position as first in the country for electricity generated through wind power, and a leading producer of solar energy.
In fact, the climate and natural resources of Texas position it to be at the forefront of alternative energy generation. In 2017, Texas produced 18% of its electrical energy from the alternative sources of wind and solar.
This particular figure is striking because it looms precipitously close to 20%—the demarcation long touted by critics of renewable energy as the ‘breaking point’ at which costs will uncontrollably increase and reliability cannot be ensured. However, though Texas’ alternative energy generation approaches 20%, its costs and reliability are stable, with retail electricity prices actually belowthe United States average.
The improbability of Texas’ standing as a successful producer of electricity using renewable resources is compounded by the state’s electrical grid isolation. Specifically, the contiguous United States is comprised of three different electric grids: the Western Interconnection, the Eastern Interconnection, and the Electric Reliability Council of Texas (ERCOT) Interconnection. Considering that Texas cannot exchange power with other states, its ability to balance and transmit energy within the state even more impressive.
Texas has plans to continue to invest in wind and solar energy for the state. Between 2018 and 2019, ERCOT had plans to increase wind energy capacity by 8700 megawatts, a near 40% increase. While solar energy presently forms only a modest portion of the state’s renewable energy sources (wind being the primary source), the state has signed interconnection agreements potentially adding 2000 megawatts of solar energy between 2018 and 2020 that will almost triple the current solar capacity of the state.
A recent study by researchers from Rice University produced findings that lend themselves to confirming the idea that not only is Texas ideally poised to take advantage of renewable resources, it may be the state best equipped to do so around the clock, effectively weaning itself off coal-produced electricity. The research, published in November of last year in the journal Renewables, Wind, Water, and Solar, suggests that Texas has the capacity to utilize wind and solar energy from different areas of the state to generate electricity throughout the day, with minimal need for battery storage.
Specifically, the researchers found that wind energy is generated at different times of day by different regions of the state, which—when supplemented with solar-generated electricity—can power the state over a 24-hour cycle.
For example, most of the wind power generated in the state currently comes from wind turbines in West Texas, which experiences the strongest winds at night and in early spring. Conversely, wind turbines on the Gulf Coast have the greatest energy generation capacity during the late afternoons of the summer, when energy demand is also at its height.
Furthermore, researchers were able to establish a renewable energy clock, as they found between 1 p.m. and 8 p.m., wind generation from the summer sea breeze on the Gulf Coast would be sufficient to supply the state, while from 8 a.m. to 6 p.m., solar energy has the capacity to supplant wind generation.
Looking forward, understanding the temporal needs and capacities of different forms of renewable energy, both within the 24-hour cycle of a day and the seasons of a year, is crucial to expanding renewable energy generation and use in Texas. As described by the senior director of systems operations of ERCOT, Dan Woodfin, “It’s all a matter of timing.” As such, this new study lends credence to the argument that Texas can be on the path toward phasing out coal-generated electricity almost entirely.