WASHINGTON, D.C. - A Department of Energy research program has achieved major milestones in the development of "smart" tools that enable cost-effective finding and production of huge gas resources lying three to five miles below the earth's surface.
Successful tests of four electronic components developed by Honeywell Inc., Plymouth, MN, point to another watershed in the successful Deep Trek research program DOE established in 2002. Deep Trek was created to address the extreme temperatures, pressures, and other harsh conditions encountered when drilling below 15,000-20,000 feet. To date, DOE has awarded eight projects under the Deep Trek program totaling over $16 million, almost $9 million of which is being contributed by research partners.
Addressing the challenges associated with tackling deep gas resources is important for the Nation. Natural gas resources lying at such great depths are contributing an ever-growing share of U.S. gas supply. For decades, America's gas production has come from large reservoirs found at depths of 5,000 feet or less. As those resources are being depleted, the search continues for the vast deep gas resources in the United States that DOE estimates at 125 trillion cubic feet (Tcf). The Nation's total proved gas reserves are estimated at 192 Tcf. Deep gas has accounted for about seven percent of America's gas supply in recent years. Given current gas demand growth, the National Petroleum Council estimates that this share will have to increase to 12 percent by 2010 if the Nation's growing gas demand is to be met.
But finding and producing these deep gas resources entails encountering temperatures that can top 400°F (205°C) and pressures that can exceed 10,000 psi. Such downhole conditions can disrupt or disable the sophisticated electronic instrumentation and other tools used to successfully direct wells to deep gas zones and to characterize the harsh subsurface environments. Without such instrumentation?often delivering data in real time?drilling becomes very challenging: very costly, slow, and often just off-target.
The challenges become more difficult the deeper the well. It is a truism in deep-gas drilling that the last 10 percent of a hole can account for 50 percent of the well's cost. So developing the electronic tools that can function in these difficult conditions can make the difference in economically securing a big chunk of America's future gas supply.
For one Deep Trek project, DOE awarded a $9.3 million, cost-shared contract to Honeywell to develop four critical high-temperature electronic components for deep-gas drilling and a manufacturing process using silica-on-insulator technology capable of withstanding the temperatures encountered at those depths.
As part of that effort, a group of oil and gas operating and service/supply companies formed a joint industry partnership (JIP) to share costs and to provide product-user input for the types of electronic components and performance specifications needed.
The DOE-sponsored project has achieved these milestones on the four key components that, as part of a larger system, will make it possible for detailed well data from the bottom of the hole to be more quickly and accurately received at the surface saving time and money. The milestones on the four key components are:
- Accomplishing an industry first by moving closer to achieving the top goal on the JIP's wish list?an electrically erasable, programmable, read-only memory (EEPROM) chip capable of withstanding the high temperatures in deep gas wells. Honeywell developed two test chips that proved that this new technology can produce circuits that will allow instructions to be written to, or read from, the EEPROM chip. The EEPROM, which is capable of retaining the data for over 1,000 hours at 225°C (437°F), is undergoing full-scale design and will be fabricated and tested over the coming year.
- Successfully testing and distributing to JIP members a precision amplifier (OpAmp), which conditions data signals received from downhole sensors. The OpAmp performed well within design specifications at 300°C for over 1,000 hours and has an operating range of -50°C to 375°C. (-58°F to 707°F).
- Achieving a first-pass success test of a field-programmable gate array (FPGA) equipped with more than 3 million transistors and 32,000 gates. A FPGA is a semiconductor device whose components and interconnections feature programmable logic. These flexible chips can be reprogrammed in the field to accommodate a change in purpose for a particular electronic circuit. The EEPROM provides instructions to the FPGA.
- Completing design and fabrication of an 18-bit analog-to-digital converter (ADC). The goal here is to develop an ADC with a 16-fold improvement in resolution from the existing standard. This kind of electronic circuit converts continuous signals to discrete digits?basically converting voltage to a binary digital number. Initial tests are under way to assess a first-pass success.
Honeywell is designing the four components to withstand the extreme heat encountered in a deep gas well. It will be the responsibility of the end user to provide packaging for these components that can also withstand the high pressures found at these depths.
Successfully commercializing these "smart well" technologies could make the difference in unlocking the potential of a critical component of America's future gas supply.