As an Exelon company, Constellation Energy is part of one of the biggest — and historically most polluting — corporations in North America. Given Exelon’s vast production energy, ranking on the PERI Toxic 100 list is perhaps not that surprising. The good news is that Exelon is upfront about its room for eco-friendly improvement and make it easy for Constellation customers to go green, too.
Keeping on top:  With deregulation, a whole host of electric resellers jumped into the market because there’s a whole lot of electricity to sell:  if Texas were a country, it’d be the 11th largest electricity consumer in the world!  Just by itself, it uses as much electricity as Spain or Great Britain!  That means there’s a whole lot of information you have to find, absorb, and process to make sure you’re getting the best rate for your needs.
Texas electricity deregulation has given millions of Houston residents and businesses the power to choose the cheapest electricity rate. According to ERCOT, over 92% of Texas homes and businesses who live in deregulated areas have switched electric companies since deregulation began in 2002. Even though electric choice in Texas has been hugely successful for energy savings, customers are still confused by the options, terminology, and overall process of switching electric providers.

You’ll also see a flat rate and a price per kWh rate for TDU or TDSP (which stand for Transmission and Distribution Utility or Transportation Distribution Service Provider). These are costs that your utility charges for delivering electricity and maintaining power lines. The costs are unique to your local utility and have nothing to do with your electricity provider.
Although electricity had been known to be produced as a result of the chemical reactions that take place in an electrolytic cell since Alessandro Volta developed the voltaic pile in 1800, its production by this means was, and still is, expensive. In 1831, Michael Faraday devised a machine that generated electricity from rotary motion, but it took almost 50 years for the technology to reach a commercially viable stage. In 1878, in the United States, Thomas Edison developed and sold a commercially viable replacement for gas lighting and heating using locally generated and distributed direct current electricity.