Texas deregulated most of the state's electricity markets in 2002, a move aimed at lowering electricity costs by letting consumers choose their own electric power providers and their own plans. Some parts of Texas continued to be regulated, including those that get power from municipal utilities, electric cooperatives and investor-owned utilities that operate outside the state's primary power grid.

Then, in 2002, Texas deregulated the electricity market and everybody cheered!  Except that, sure, deregulation opened up the market to competition that may (or may not) have resulted in lower rates, but it introduced a whole host of other issues.  These issues may not have been factors before but now they’re critical when you’re on the look-out for cheap Houston electricity providers.

Electricity cannot be stored as easily as gas, it is produced at the exact moment of demand. All of the factors of supply and demand will therefore have an immediate impact on the price of electricity on the spot market. In addition to production costs, electricity prices are set by supply and demand.[120] However, some fundamental drivers are the most likely to be considered.
You can organize and shop by pricing at YOUR individual usage level, which allows you to shop and compare energy plans based on the rates you’ll actually see appear on your bill, inclusive of taxes and hidden fees. You won’t be misled by the “teaser rates” tied with higher usage levels that many homes never experience, as their usage level never reaches that pricing tier.