Electricity rates in Texas are not fixed. Your rate can vary greatly depending on your usage and your electric plan. Some plans have relatively flat rates, while others can be all over the place. This means that you could end up paying 7¢ for 999 kWhs and 8.5¢ for 1001 kWhs. That would be a 16% increase because you microwaved a few potatoes. Learn more on the different plan types here.
Fort Worth has, for the most part, followed in the footsteps of the state. In 2013, the American Council for Energy Efficiency ranked Fort Worth 26th in the list of America's most energy-efficient cities. The use of green energy in Fort Worth will continue to rise as the city's new Sustainability Task Force aims to make the city's development and growth more sustainable.