Tiny radios guide oil drilling

University of Houston (UH) engineers have developed a more efficient system of well logging based around radios the size of a grain of sand.

The UH Well Logging Laboratory researchers say their method of transmitting data from deep within oil wells will better guide the drilling process and could reduce consumer oil prices.

The biggest challenge in transmitting drilling information is the extreme conditions encountered in oil wells, as neither sending data through wires nor via standard wireless communication is possible. Temperatures in deep wells routinely surpass 300 degrees Fahrenheit and pressure exceeds 20,000 pounds per square inch.

The current method uses a small pump near the drill bit repeatedly expanding and contracting, which causes vibrations in the mud at the top of the well that are translated into data at the rate of about 10 bits per second. However, this information cannot be analysed quickly enough to be used in real time.

The new system uses micro-electrical-mechanical-system (MEMS) technology that could increase the data transfer rate 100-fold to as much as one kilobit per second. MEMS-based technology enables the creation of near-microscopic machines on silicon wafers, with well logging researchers using this technique to develop a series of MEMS-based radios, each no larger than a grain of sand.

As an oil well is drilled, these radios are distributed every 1.83 metres into the mud that fills the well, with the radio at the bottom of the well receiving data from the logging equipment. That information is then transferred up the well from radio to radio until it reaches the people on the surface.