Friday, July 19, 2013

Shale Gas Fracking or Coal Gasification

America has long been rich in hydrocarbon energy.  That's great for Joe Six Pack and his fellow energy hogs who forget to turn off a light when they leave a room.  The country's remaining reserves of coal and natural gas are still plentiful but are more expensive to extract than ever.  Choosing between gas and coal is not easy.

The US Potential Gas Committee has published estimates of natural gas reserves for decades using rigorous peer-reviewed methods.  The Committee estimated that the US's recoverable gas reserves stood at 2.38 Tcf at the end of 2012 with no caveat for expected production timelines or market prices.  The New York Times's "Drilling Down" series exposed the hype some shale gas enthusiasts had pushed on the public.  Large US gas reserves are not necessarily cheap or easy to obtain.

Shale gas may be cheaper and cleaner to burn than coal but that does not mean its extraction is without cost. Methane is still a greenhouse gas and its uncontrolled escape exposes the atmosphere to global warming.  That's why monitoring orphan gas leakage from wells and pipelines is important for the energy sector.

I will go out on a limb to suggest that the risk of groundwater contamination from fracking is overblown.  The GAO-12-732 found no evidence of aquifer contamination from fracking.  Oil companies already know how to purge contaminated water from a well by plugging it at the bottom and creating air pressure that sucks contaminants out of a compromised bore hole.  The scene in the documentary film Gasland of a water faucet lighting on fire displayed the results of biogenic methane gas unrelated to oil and gas exploration.

Fracking's impact on surface topology also appears to be negligible.  A fracking well's surface footprint is 5-7 acres for each well pad, but horizontal drilling means several wells can fit on a single well pad to save space.  Surface traffic into rural areas will increase as trucks bring in large amounts of water to sustain fracking, but refer again to that GAO-12-732 study above which was inconclusive on the impact of surface disturbance.  The GAO's 2013 High Risk Report concluded that the management of oil and gas royalties from production on federal lands needs improvement because of uncertainty over monitoring and revenue collection.  It all comes down to money, folks.  Uncle Sam will ignore fracking's potentially unknown impact on surface degradation if it gets a more accurate account of the enormous revenue it generates.

Trucking in all that water means someone else doesn't get to use it.  The "water wars" of the Western states have always been pretty intense between environmentalists and farmers.  Introducing fracking wells' need for water may end those wars unexpectedly because energy companies are rich enough to outbid other parties.

Fracking may have some common cause with the geothermal energy sector.  Injecting water into deep wells does induce seismic activity.  LBL's Earth Sciences Division has studied induced seismicity for years in the context of energy exploration.  It would be great if the geothermal sector could partner with the oil and gas sector by sharing data on deep well injection because they could probably learn from each other.  Both sectors should also peruse the USGS Earthquake Hazards Program data to see where their drilling is likely to raise their costs if they get hit with lawsuits from earthquake victims.

If you don't like the headaches involved with shale gas, you won't like the coal sector either.  The current Administration seems determined to make life difficult for the coal sector with increased regulatory attention.  Goal gasification in situ may provide a favorable solution.  The heat transfer to the surface generates electricity and the carbon byproduct stays locked in the Earth's crust away from the atmosphere.  DOE's support for the FutureGen coal plant conversion project shows that the Administration is willing to back a demonstrated carbon capture technology for the coal sector.  One big potential drawback to coal gasification is the uncertain means of turning off the thermal reaction underground.  I recently had a conversation with a former energy company executive who mentioned some underground coal mine fires in Pennsylvania that have burned for decades and then migrated to consume other deposits.  He had the same concern about extracting methane hydrates from Arctic tundra and the frozen ocean floor.  Taking out too much at once may cause an unpredictable reaction.

California is set to play a big role in satisfying America's future energy needs.  The Monterey Shale Formation may be the biggest oil-bearing formation in the US.  Getting energy out will be hard because of its complex geology.  I predict it's going to happen anyway.  Ignore the political noise and focus on the money.  America is going to build clean coal plants, lay the Keystone-Xcel pipeline, and frack California's shale.  The energy companies that line up first will be minting money for years.