Luminant, a subsidiary of Energy Future Holdings, has just completed the second unit of its Oak Grove 1,600 MW coal-based plant in Robertson County, Texas. The 800 MW Unit 2 plant is in the final testing phase while Unit 1 came online in December 2009. Oak Grove is the first pulverised coal plant, in the US, to utilise carbon sorbent injection technology to remove mercury and should, according to the company, be capable of powering almost 850,000 average Texas homes when both Units 1 and 2 are combined. Along with the 581MW Sandow 5, another coal based plant, this means that Luminant can now provide power to more than 1.15 million Texas homes.

The pulverised lignite coal plant‘s advanced environmental controls are expected to reduce emissions (NOx, SO2, and PM) by 70% over national coal plant averages and will have lower emissions rates than any existing lignite plant in Texas – a far cry from 2006 when the Oak Grove plans were targeted by a lawsuit based on the Clean Air Act. Luminant, formerly TXU, began building Oak Grove in 2007.

Texan electricity companies have said that new coal plants are needed to meet the state’s growing demand for power and to diversify fuel sources. Currently around half of the power plants in Texas use gas as a primary fuel while another fifth are dual fuelled by oil and gas.

According to the Electric Reliability Council of Texas, which manages the electric grid for roughly 75% of Texas, only 18% of power plants are coal-fired. However the National Energy Technology Laboratory has estimated that 13,755 MW of coal-based capacity is under construction as of January 2010.