Sign up | Login with →

Comments by Wilmot McCutchen Subscribe

On Sequestration on Shaky Ground

Post-combustion CO2 capture by chemistry also looks dubious.  https://www.sciencenews.org/article/carbon-capture-and-storage-finally-approaching-debut   Amine sweetening, to remove CO2 from natural gas, is a mature technology (from the '30s) but it can't possibly scale from the oil field to what's needed for a coal plant (5,000 tpd).  Water consumption would double.  Quenching the hot flue gas to 30-60C so the amine sorbents can work is possible but not economical.  Wet cooling at thermal power plants already consumes more fresh water than any other use, and doubling that waste of water during a drought is not a realistic plan.  The energy penalty of chemical capture (20-35%) is another strike against conventional CCS.  Weakening power generation during expanding demand is a sacrifice that will be hard to sell to the developing world.  Strike three is the impossibiity of secure storage underground at the scale required.  With these three strikes against it, chemical capture and sequestration is clearly not a viable option.  But the goal of mitigating global warming could be achieved by kinematic separation in open von Karman flow (for CO2 capture by stripping the nitrogen ballast) and CO2 cracking (by radial counterflow shear electrolysis).

 

  

January 23, 2015    View Comment    

On Keystone XL: Let's Make a Megadeal and Get Congress to Fulfill a Cleantech Wishlist

The price of oil (<$50) now moots the KXL project.  So why do the proponents need a pipeline over the Ogallalla aquifer?  For export?  How is that good for America, or for Canada?

January 22, 2015    View Comment    

On Sequestration on Shaky Ground

Shaky indeed.  Cracking the bedrock and salting the groundwater are the likely outcome of CO2 sequestration, if it's even possible at the scale of 2 billion tonnes per year.  Trying to squeeze supercritical fluid into rock where the pore space is full of very salty water makes no sense.   https://www.sciencenews.org/article/pumping-carbon-dioxide-deep-underground-may-trigger-earthquakes

 

January 22, 2015    View Comment    

On WSJ Gets it Wrong on 'Why Peak Oil Predictions Haven't Come True'

Shale oil has become so cheap in the US that peak oil fears now seem to have been groundless.  And natural gas is now so abundant that in North Dakota it just gets flared into the atmosphere.  Water is lavishly consumed and polluted by fracking and oil sands extraction, despite the Drought.  So it would seem that something like the loaves and fishes is going on with what we of little faith used to believe were finite natural resources.

The money supply, too, expands by accrual of compound interest without limit.  So does the debt of students  reduced to peonage by compound interest on debts they will never be able to pay or discharge in bankruptcy.  Evidently the Jubilee has been repealed, as well as the laws of nature.  Party on, 1%!

Thanks, Gail, for your lucid dissent.  Recent news might explain weak oil prices: the Rossi reactor.  http://www.extremetech.com/extreme/191754-cold-fusion-reactor-verified-by-third-party-researchers-seems-to-have-1-million-times-the-energy-density-of-gasoline

October 12, 2014    View Comment    

On Are Carbon Capture and Storage and Biomass Indispensable in the Fight Against Climate Change?

Neither CCS nor biofuels offer a path to CO2 management because they can't possibly scale to the size of the problem. By 2035 the EIA forecasts annual US CO2 emissions of 6.32 billion metric tons, 38% of which (2.40 billion) will be from US coal plants alone. There's no space underground to store that much CO2 every year, and trying to do so will endanger the water supply.

CCS (conventionally understood to mean amine scrubbing for CO2 capture and underground storage for sequestration) is fundamentally impractical because of water issues. Energy pundits tend to neglect water issues as beyond their narrowly siloed expertise, but water is a deal-breaker.  Amine scrubbing will double the already huge water consumption of coal plants. Sequestration at the scale required, even if practical, will displace salty formation fluids, which might eventually contaminate the groundwater.

Extrapolating EOR experience to justify CCS is an elementary error. The huge Permian Basin oil field’s current annual enhanced oil recovery (EOR) demand is only 7 million tons of CO2, about the annual output of a single 1 GW coal-fired power plant. See this article from POWER magazine at http://www.powermag.com/carbon-control-the-long-road-ahead/. Clearly, EOR in depleted oil and gas reservoirs can't handle the expected 2 BILLION tonne volume of CO2 that must be stored each year just from coal power generation in the US alone. CO2 for EOR is of benefit to the oil companies, but no help for global warming.

Deep saline formations have lots of pore space, i.e. spaces between grains in the rock, but -- unlike depleted reservoirs where EOR has worked -- the pores in the rock are full of very salty brine at high pressure. For example, the FutureGen sequestation will displace 47,500 ppm brine (saltier than seawater) from the Mt. Simon formation under Illinois. No one knows or evidently cares where this brine ends up.  There is no plan to handle it.

Moving the brine out and the CO2 in will be impossible at the scale of billions of tonnes each year. No one will insure the risk.  We hear a lot about the 25 years of successful experience with EOR, but EOR in depleted reservoirs (empty tanks) is immaterial to the viability of utility-scale CO2 sequestration, which must be in deep saline formations (full tanks).

Once injected into the formation, the CO2 would have to be securely contained.  Closure is of the essence.  Experience with an open system, like EOR, is inapposite. An open system for secure storage is nonsense. This fundamental point seems to have been overlooked. In 2010, a sobering article appeared in the refereed Journal of Petroleum Science and Engineering (70:123-130), authored by two distinguished full professors of petroleum engineering, Christine Ehlig-Economides and Michael J. Economides. Here's a quote from the abstract:

“Published reports on the potential for sequestration fail to address the necessity of storing CO2 in a closed system. Our calculations suggest that the volume of liquid or supercritical CO2 to be disposed cannot exceed more than about 1% of pore space. This will require from 5 to 20 times more underground reservoir volume than has been envisioned by many, and it renders geologic sequestration of CO2 a profoundly non-feasible option for the management of CO2 emissions.”

Cramming 2 billion tonnes each year into deep saline formations is a vain hope to begin with. The danger of saline intrusion into the groundwater and CO2 plumes erupting and killing people must be weighed against the trivial benefit to global warming, which is the ostensible motivation for FutureGen. If it's expected to be an open system, like EOR, where there is mass flow through system boundaries, then secure containment of the brine and the CO2 will not be possible. Better to save the billion dollars to be wasted on this futile and dangerous experiment.

 Solid biofuels require water to grow, and they need to be dried so they can be transported and burned. The energy and water needed to deliver this low-grade fuel need to be taken into account. Liquid biofuels, like corn ethanol, have disappointed, despite confident predictions. Gaseous biofuels from waste-to-energy schemes involving anaerobic digestion (AD) create a water pollution problem in order to solve an air pollution problem, which they might even aggravate. AD sludge (digestate) is heavy to transport and leaches nitrates into the groundwater. The AD product, methane, is a potent greenhouse gas that has so little commercial value (due to the abundance of methane from shale oil production) that it just gets flared so it won't get in the atmosphere. Biofuels might have a small role in niche applications (e.g. sugar ethanol in Brazil).

September 11, 2014    View Comment    

On Living in a Renewables Distortion Field

Scalabiity of non-hydro renewables is the missing link.  Small bore solutions to the world's expanding prosperity power demand have no chance of making a real difference in climate control.  People used to think a human could fly by flapping artificial wings.  The consensus view that renewables can rapidly scale from their present 6% to supplant coal is wrong too. 

March 22, 2014    View Comment    

On The Cleantech Crash: 60 Minutes Asks the Wrong Question

What's missing is technology assessment, where the merits could be vetted.  Someplace for the truth to have  a fair shot before DOE makes up its mind to spend money.  The 20% cost sharing requirement of ARPA-E, which is touted as DOE's long shot effort, makes sure only big companies get to the batter's box, and ARPA-E projects have not produced any home runs, just bunts and a few singles. 

Cleantech is a tainted brand which has come to mean only wind, solar, and biofuels -- non-hydro renewables -- and efficiency tweaks like metering and software.  It sounds comprehensive of all pollution control technology, but in practice is only about alternative energy, which is not attractive when natural gas from fracking is abundant, and shale oil cheap.       

January 13, 2014    View Comment    

On Limitations of Unreliable Energy Sources, aka 'Renewables'

Order of magnitude sanity check from the EPA:  "Non-hydroelectric renewable energy refers to electricity supplied from the following renewable sources of power: solar, geothermal, biomass, landfill gas, and wind. Although installation of these renewable energy resources is growing, non-hydro renewable energy is currently responsible for less than two percent of the electricity generation in the United States."  http://www.epa.gov/cleanenergy/energy-and-you/affect/non-hydro.html

November 23, 2013    View Comment    

On Impacts of Shutting Down Most US Coal Power, Part 2

"... non-hydro renewable energy is currently responsible for less than two percent of the electricity generation in the United States."  http://www.epa.gov/cleanenergy/energy-and-you/affect/non-hydro.html

Two percent.  They're midgets, and the EPA knows this. 

But the EPA has faith that the technology will appear.  Maybe cold fusion for steam generation from tritiated water cavitation.  Maybe getting more power out of the turbine exhaust steam at coal and nuclear plants, rather than wasting all that energy as latent heat into the atmosphere.  Maybe vortex separation of mercury, ash, and even CO2 from smokestacks, so the long-promised "clean coal" will become a reality.  

October 25, 2013    View Comment    

On Carbon Capture And Storage: One Step Forward, One Step Back

DOE has an institutional blind spot for water issues because energy experts tend to be ignorant outside their narrow little silos, as the GAO found.  Ruining the groundwater to prevent global warming would not make sense.  Congress ordered DOE to report on the water-energy nexus in 2005, and it's still not done.

October 17, 2013    View Comment    

On Carbon Capture And Storage: One Step Forward, One Step Back

Good article.  Perseverance in absurdity (other example: Vietnam) seems to be independent of reality, so such warnings will probably be disregarded and billions will be wasted on futile CCS projects that are of no real benefit except to the oil companies, as a source of cheap CO2 for their oil scavenging operations (EOR). 

October 17, 2013    View Comment    

On Impacts of Shutting Down All US Coal Power: Part 1

EOR (CO2 used for oil extraction from depleted reservoirs) is tiny compared with utility-scale CO2 storage from America's coal fleet.  The lifetime emissions of a single coal plant would require the pore space of a giant oil field (4.1 billion barrels).  So EPA's dream of CCS depends on storage of supercritical CO2 in deep saline formations, which petroleum engineering experts deem "profoundly non feasible." Extrapolating EOR to CCS is a mistake. 

Pore space in deep saline formations is full of high pressure brine that is very salty.  If indeed it is possible to cram supercritical CO2 into rocks, where does the displaced brine go?  Buoyant and fizzy from CO2 injection, eventually brine is going to wind up in the fresh groundwater that American agriculture depends on.  And fugitive plumes of CO2 will erupt and kill people. 

Coal is worth saving because, until scalable cold fusion is discovered, coal will be the only way to meet baseload power demand in China and India.  Non-hydro renewables (wind, solar, biofuels, and geothermal) are midgets that can never scale to supplant coal.  But coal can't be saved by chemical capture and underground dumping of CO2.  Some other form of CCS might work, if DOE and EPA would look for it.

October 6, 2013    View Comment