In environmental impact, results are mixed. With the ability to invest profits to satisfy further energy demand, producers like TXU are proposing eleven new coal-fired powerplants. Coal powerplants are cheaper than natural gas-fired powerplants, but produce more pollution. When the private equity firms Kohlberg Kravis Roberts and the Texas Pacific Group announced the take-over of TXU, the company which was known for charging the highest rates in the state and were losing customers, they called off plans for eight of the coal plants. TXU had invested more heavily in the other three. A few weeks later the buyers announced plans for two cleaner IGCC coal plants.
Due to the increased usage of natural gas immediately after deregulation, new-era energy tools such as wind power and smart-grid technology were greatly aided. Texas' first "renewable portfolio standard" — or requirement that the state's utilities get a certain amount of their power from renewable energy like wind — was signed into law in 1999, as part of the same legislation that deregulated the electric market.
In this free market competing electricity retailers buy electricity wholesale from private power generators to sell at retail to around 85% of Texas residents. The partnership between generators and retailers is governed by the Electric Reliability Council of Texas, or ERCOT, which attempts to balance the power grid’s electricity supply and demand by purchasing small amounts of electricity at 15-minute intervals throughout the day.