By the OGJ Online Staff
HOUSTON, Feb. 26�The US Department of Energy said Monday it has launched a research effort to see if high-powered lasers can be adapted for oil and gas drilling.
The research, which will build on a basic study completed by the gas industry in 1999, will be conducted by the Gas Technology Institute (GTI), DOE's National Energy Technology Laboratory, and several other project partners.
DOE said if drilling with lasers proves viable, it could be the most radical change in drilling technology in the last century. It said the basic mechanical drilling method has remained essentially the same since rotary drilling supplanted cable tool drilling at the turn of the last century.
It said laser drilling would transfer energy from lasers on the surface down a borehole by a fiber optic bundle to a series of lenses that would direct the laser light to the rock face.
"Researchers believe that state-of-the-art lasers have the potential to penetrate rock at 10-100 times faster than conventional boring technologies�a huge benefit in reducing the high costs of operating a drill rig," DOE said.
It said a typical oil or gas well on land costs $400,000 to drill, while costs for an offshore well average nearly $4.5 million. Costs can be higher in deeper or more difficult drilling terrains. DOE said reducing the time a drill rig remains on site can lower costs and make previously uneconomic gas or oil deposits commercially attractive.
"The earlier study by the Gas Research Institute (GRI) showed that laser systems now can provide more than enough power to cut rock. Because the laser head does not contact the rock, there is no need to stop drilling to replace a mechanical bit.
"Moreover, researchers believe that lasers have the ability to melt the rock in a way that creates a ceramic sheath in the wellbore, eliminating the expense of buying and setting steel well casing. A laser system could also contain a variety of downhole sensors�including visual imaging systems�that could communicate with the surface through the fiber optic cabling."
DOE selected the laser drilling project last year in a competition for new ideas to improve the way companies find and produce natural gas. The proposal was submitted by the GRI, which subsequently combined with the Institute of Gas Technology to form GTI, based in Chicago.
A drawback of laser drilling has been the large amounts of energy required. The 1997-99 GRI study indicated, however, that energy needs may have been overestimated.
DOE said, "One of the primary objectives of the new study will be to obtain much more precise measurements of the energy requirements needed to transmit light from surface lasers down a borehole with enough power to bore through rocks as much as 20,000 ft or more below the surface.
"Another aspect of the study will be to determine if sending the laser light in sharp pulses, rather than as a continuous stream, could further increase the rate of rock penetration. Pulsed lasers have been used for better performance in cutting steel, for example.
"A third aspect will be to determine if lasers can be used in the presence of drilling fluids. The technical challenge will be to determine whether too much laser energy is expended to vaporize and clear away the fluid where the drilling is occurring."
DOE said later in the project, researchers could examine if lasers could be used to perforate wells.
The federal government will pay $500,000 of the cost of the 3-year study while GTI will pay $214,000. Joining the research effort will be the Colorado School of Mines, Argonne National Laboratory (Laser Applications Laboratory), Halliburton Energy Services, and Petroleos de Venezuela SA.