Great Ideas on Energy
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November 13, 2012
A recent issue of The Alcalde, UT's Alumni Magazine, featured 22 Great Ideas on Energy — almost 20 percent showcased research from PGE.
A century ago, The University of Texas was built on energy. Some sources may have changed, but as these brilliant innovations prove, the university is still charging ahead. See how four professors within the PGE department are recalculating the way we think about and produce energy. Read the full story on The Alcalde's website.
Use nanoparticles to find oil
One hundred nineteen billion barrels. That's one estimate of how much oil could be recoverable from American oilfields — including some judged no longer worth pumping. That's because the more oil you pump out of a reservoir, the harder it becomes to get what’s left.
Now professors Steven Bryant and Keith Johnston have devised nanoparticles of silica and iron oxide that can be mixed into that fluid. These tiny particles could help us tap into that 119 billion barrels — and tuck greenhouse gases underground in the process.
After fluids are injected into an oil well, they flow back out to production wells, bringing oil up. That's called sweeping the reservoir. Carbon dioxide is a popular "broom" because it's a great solvent for underground oil.
The trouble is that under typical temperatures and pressures of oil reservoirs, CO2 is buoyant and runny, so it can find shortcuts back up rather than herding oil up through the reservoir’s porous rocks while remaining underground. Engineers can make the CO2 better able to push oil up by mixing it with brine and surfactants to form a stiff foam. The downside is that these foams are quick to separate into their component liquids.
That's where Bryant and Johnston’s nanoparticles come in. The tiny particles attach to CO2 bubbles, preventing them from coalescing. "Once you get [the nanoparticles] there, it's difficult to knock them off," Bryant says. "You get this inherent stability." As a bonus, the stabilized foam is likelier to stay put underground, taking atmospheric CO2 out of circulation. — Jenny Blair
Use less water in fracking
Hydraulic fracturing is a process in which fractures in rocks below the earth's surface are opened and widened by injecting liquids and chemicals at high pressure to extract natural gas and oil. One of the concerns about what is often called "fracking" is that the process can use a tremendous amount of water. For example, Texas' Barnett Shale requires 2.7 million gallons of water per well. As Texas remains drought-ridden, Professor Mukul Sharma and grad student Lionel Ribeiro are devoting lab time to developing water-saving techniques that will not only decrease dependence, but also enhance natural gas production.
Sharma, who leads the world's largest academic research group on the subject, saw that no one else was addressing the issue head on, so his team dedicated itself to discovering solutions.
"We want to reduce the environmental foot- print of hydraulic fracturing, and there are three areas that we are working on that provide the best means of meeting that goal," Sharma says. "These include safe-produced water disposal, reducing fresh water use in oil and gas production, and fracturing water reuse and recycling."
Armed with this knowledge of what will have the most impact, Sharma and his research group developed a tool to address fracking issues.
"We have built the first fully compositional hydraulic fracturing simulator that is used for fracture design," Sharma says. "It accounts for three important aspects of the problem critical to accurately predicting the fracture: changes in fluid density, temperature and fluid composition during fracturing."
Ribeiro focuses on the reduction of water usage through CO2 and nitrogen foams. These foams reduce the need for water by about 70 percent, and the use of pure CO2 gas almost completely eliminates water from the equation.
"Beyond the environmental impact, the inter- actions between the rock and the injected water can hinder production," Ribeiro says. "The CO2 and nitrogen foams outperform water fractures because they don't cause as much damage to the fracture and the rock maintains its permeability to gas, so overall it is a win-win scenario."
Sharma and Ribeiro are testing the model in the field and getting positive feedback. If the technique becomes an industry standard, it will take a weight off of Texas' water sources, allow for more efficient gas production, and provide more abundant natural gas. — Katharine Grieve
Create a futuristic transit system
Texas' capital city ranks among the country's most gridlocked, 2012 could be the costliest year ever at the pump, and our carbon footprint grows ever larger.
The chairman of UT's Petroleum and Geosystems Engineering Department, Tad Patzek, proposes a solution: podcars.
Podcars are driverless vehicles that run on electricity-powered guideways suspended over existing highways. The concept may seem futuristic, but such cars have already been launched in countries like Sweden and England.
"Podcars cost 10 times less to operate and are 11 times more energy-efficient than today's vehicles," Patzek points out. "Also, photovoltaic panels can be installed on the guideways to augment power supply."
Patzek is moving the concept forward in the U.S. by collaborating with Ron Swenson, one of the scientists leading the charge on podcar development. They both serve on the board of the Association for the Study of Peak Oil, which examines the issues around fossil fuel production.
Podcars are already transporting people at one of the world's busiest airports, Heathrow in London. Given that, Patzek says, "there is no reason why they couldn't move people between the main UT campus in Austin and the Pickle campus 10 miles north. This would be a convincing demonstration project for the city." — Katharine Grieve
Use automation to improve drilling efficiency and safety
For 20 years, Eric van Oort worked at companies like Shell, seeing the struggle of oil and gas companies to meet their safety goal of zero people hurt on the job. Now a UT petroleum engineering professor, van Oort saw a solution: automate drilling.
"Drilling is potentially dangerous, with rig staff and heavy machinery operating in the same tight space," he says. "So why not let machines do the hazardous work?"
On its face, automation for safety isn't a new idea. Airplanes have autopilot; cars have airbags. Now van Oort is on a mission to help oil and gas catch up. As the industry works overtime to ensure that a disaster like the 2010 Deepwater Horizon spill never happens again, automation is crucial. Algorithms can detect changes in rig data consistently and quickly — preventing problems early.
There's also a pressing challenge to drill more efficiently. The low price of natural gas, says van Oort, pushes operators to be more efficient. Automating best practices can help reduce waste and improve speed. Van Oort is cautious but confident.
"The oil industry is known for being conservative, but it's changing rapidly, and for the better," he says. "This is the future."— Rose Cahalan
