Dual turbine power and wellbore communications apparatus

A method of performing an operational action with a downhole system, the method comprising:

• conveying a downhole string of the downhole system into a wellbore;
• flowing a fluid through the downhole string at a first flow rate within a first flow rate range;
• generating electrical energy using a first turbine generator configured to generate electrical energy when the flow rate is within the first flow rate range;
• flowing the fluid at a second flow rate within a second flow rate range;
• generating electrical energy using a second turbine generator configured to generate electrical energy when the flow rate is within a second flow rate range different than the first flow rate range;
• transmitting a pressure pulse communicative of data generated downhole using a first pulser powered by one of the first turbine generator and the second turbine generator;
• receiving the pressure pulse at a sensor at a surface location;
• and
• performing an operational action based on the data communicated by the pressure pulse.