November 16, 2015 § 2 Comments
NOx (oxides of nitrogen) are a Front of the Box pollutant. The effects are short term and on health, in contrast to CO2 whose effects are more in the long term, on targets such as severe weather and drought, leaving some room for doubt relative to causality. Consequently, NOx emissions from devices such as automobiles could be expected to be a public concern. Yet, much of the attention from the VW emissions cheating episode is directed to the behavior and not the attendant pollution. In fact the reporting has shown that much of the industry has cheated in one way or another. In Europe the emissions testing is done by the companies with no regulatory oversight. The use of non-standard vehicles during the tests is a common practice to which everybody turns a blind eye. For mileage testing cars are routinely stripped of wind drag components such as wing mirrors. The real world kilometers per liter are in the vicinity of 35% worse than in these tests.
VW managed to do something that was shocking even against this backdrop of routine avoidance of emissions regulations. Interestingly evidence is piling up to indicate that the “defeat devices” they use (more on it below) may not have explicitly violated any European strictures. No such doubt exists in the US. The issues that I will address below are: 1. what was the technology for NOx reduction they employed, and 2. how was it circumvented and why.
When a diesel engine is burnt “lean”, it performs the best, especially with respect to fuel economy. This condition is defined as air somewhat in excess of the stoichiometric amount required to combust the fuel. Less unburnt fuel is also good on emissions. However, the excess air causes more production of oxides of nitrogen, NOx. This must be reduced in the exhaust gas stream.
VW use a technology known as the Lean NOx Trap (LNT). There are two steps (there is a preliminary step which we will skip for this discussion for simplicity). In the first NOx is captured on a coating that adsorbs NOx. Adsorption is a surface phenomenon that is easily reversed. When the coating is considered filled up, the second step kicks into gear. This involves removing the NOx to regenerate the coating activity. This is the key step that got VW in trouble. The NOx is reduced to nitrogen and CO2 on a special catalyst by reacting it with some mixture of hydrocarbons, hydrogen and CO. This mixture is created by switching the engine to a “rich” burn mode, away from the lean. The reactant is the fuel from the cylinders that is only partially combusted. Not surprisingly, during that time, engine performance drops for reasons noted above. The gas mileage reduces as does the torque.
VW was attempting to penetrate the US market with diesels. This was part of an overall goal of being the top seller worldwide. The US consumer had been recalcitrant compared to the Europeans. Also, the NOx regulations in the US were stricter. In the US the regulators do spot checks. It appears that the decision was made to “defeat” the device during normal road operation. This was achieved through a reasonably sophisticated algorithm which detected that the vehicle was in a test mode. When in this mode the engine was allowed to run rich for the needed period to perform the function of the LNT. But importantly, in normal driving the vehicle ran lean all the time, giving the needed performance in miles per gallon and torque. In other words it was peppy (high engine torque) with high mileage and was great on emissions. Keep in mind that all diesel are better on mileage than gasoline engines. In part this is because the fuel has about 10% more energy content and in part because diesel engines run on much higher compression ratios. But for decades they have had a reputation for being smoky and smelly. This is no longer the case. Particulate filters take away the smoky aspect. The only remaining concern had been the NOx emissions. VW claimed to have met those while delivering a superior driving experience. There is no dispute that they cheated. The key point is not so much the cheating on the testing, but that buyers expecting to get a low emissions car were not getting one.
What were the alternatives to LNT available to them, and why they chose not to use those, are the US rules too stringent to be achieved by small low cost cars, is diesel simply not viable for these cars, will electric cars and hybrids be advantaged, these are all topics for the next post.
June 2, 2015 § 2 Comments
A century or so ago Tesla and Westinghouse beat Edison in the war of electricity transmission and AC became our way of life. In an odd modern twist, the first, and most famous electric car is named after Tesla, but runs on DC current. Most electronics run on DC, but AC continues as the transmission medium, dooming us to the ubiquitous “brick” converting to DC for our phone charging, computers and so on. The DC worm is turning. In some measure this is due to fact that the output of solar panels is in the DC mode, as is that of back up batteries. Organizations such as the EMerge Alliance are making some inroads in commercial buildings with a proposed 24 V wiring standard. But curiously the lead for the resurgence of DC usage in homes may well be from India.
wtih apologies to the Australian rock group
Power shortages are a way of life in most developing nations. Consumers who can afford it have back up devices which are inherently inefficient. The rest simply do without for several hours at a time often each day. Most governments respond with more power plants, which in many countries are coal fired, with attendant effects on public health and climate change. The Indian Institute of Technology, Madras (IITM), has initiated the Uninterrupted DC (UDC) program. This is an innovative scheme to provide continuous power even during the intervals of shortage. This is accomplished through some changes in the grid system at a sub-station level, combined with households using energy-efficient DC devices. Widespread acceptance of this concept will require some equipment to be redesigned. But many other common devices such as computers and cell phone chargers, as well as energy efficient LED lights already operate on DC. DC powered fans are already available. Large scale adoption will improve consumer experience through uninterrupted service and reduced costs and have a net positive impact on the environment.
India is poised for rapid economic growth. This growth brings with it increased requirement for electric power at the industrial and consumer levels. Chronic power shortages especially at peak intervals have to be managed. Industrial consumers rely on diesel powered back up power, which has its own issues with particulate matter emissions. Private consumers have two choices. Those that can afford to install inverters in each home which charge batteries for use during the outage. AC power is converted to DC for storage and then reverted to AC for running devices. Each of these steps has an associated loss. Furthermore, when the power comes back on, each of these systems charges up for the next time, creating a surge on the grid. The UDC system is targeted at providing limited service continuously while at the same time reducing the overall energy consumption. In essence this is an aspect of Demand Side Management. It fits with the overall direction from the International Energy Agency that any reasonable carbon emission targets in 2050 can only be met by using 50% less. India and China are routinely cited as major contributors to atmospheric carbon due in part to reliance on coal for power. Program such as UDC could lead the way to mitigating the environmental impact of coal for power. Uninterrupted DC (UDC) technology is so named by its inventors, to emphasize that it delivers a useful quantity of power in uninterrupted (24×7) mode, and in DC form, incentivizing use of efficient DC appliances. Devices powered by DC can be 50% or more efficient than their AC counterparts. Use of such devices and the systems to enable these are central to the concept of UDC. In low to moderate income households the critical devices for continuous operations are lights, fans and either cell phone chargers or LED televisions. A home that typically uses 1 kW of AC peak power, could get by with 100 W of DC with somewhat reduced functionality.
The UDPM is a new device at the spot of the current meter and is the heart of the UDC system. It incorporates the existing AC meter and adds capability to split the incoming power into a DC 48 V line and a conventional AC 230 V line. The house is rewired to accommodate a few low voltage lines to run the low voltage devices. In a peak demand period the sub-station will send 10% of the normal electricity to each home instead of turning it off, as is the current practice. The UDPM at the home will utilize it solely for the 48 V service. During the period of the brownout the sub-station steps down the power to 4.2 kV from the normal 11 kV. The UDPM detects this voltage drop, cuts the AC output, and limits the 48V DC output to, say, 100W. This robust signaling is another innovative feature of the system. Importantly, during normal operation, both home circuits are in use, but the DC output is always limited to the brownout level of 100W. This allows for the utilization of the low power DC devices all the time and not solely during the brownouts. The consequential lowering in the power bill is a positive for the homeowner, and the continuous use incentivizes the manufacturer.
Fit with Solar Energy: While the initial focus of UDC is reasonably moderate income homeowners, the middle and upper-middle class segment could also be addressed through the addition of solar energy. This source is DC power to begin with and is artificially converted to AC for conventional appliances. This can still be allowed while a significant portion could be used in the DC mode. Typical solar outputs are 12 V and four together add up to 48 V. Perhaps this is why IITM chose that particular voltage, not to mention that 48V has been the standard DC voltage for telecom equipment worldwide. 12 V is also the output of standard lead-acid storage batteries. Ultimately one could expect even compressors for refrigerators to go the DC mode. Air conditioning would be next, but for the drier parts of India air coolers using water function quite well and those components are DC amenable.
Conclusions: UDC is an elegant addition to the Demand Side Management arsenal. It generally falls in the category of technology solutions although a small element of behavioral change exists. Utilities will undoubtedly welcome this development. Since the changes have to be at the sub-station level, the conversion could be staged community by community. IITM reports that pilots have already found word of mouth spread of the demand. An innovative business model may be necessary to pay for the modifications in the homes. Widespread use of this technology is certain to reduce the overall national burden on the power sector. Countries could justifiably claim advances in GHG mitigation.
April 30, 2015 § Leave a comment
A recent issue of the Economist points out that types of innovation have changed over the last hundred and fifty years. The piece is based on a recent paper in the Journal of the Royal Society Interface and it relies upon data from the US Patent Office. The primary conclusion is that in the early years of patenting new classes of invention occurred, whereas in the modern day inventions rely on using combinations of existing classes. William Shockley’s transistor is cited as creating a new class, while Edison is seen as merely combining the classes represented by heated filaments, electrical supply and a vacuum.
At first blush, Edison’s light bulb being relegated to a mere “combinatorial” class is surprising in part because many consider it to be the quintessential invention. The Aha moment signaled by a light bulb cartoon is in the annals. So what gives? Basically, the authors believe that inventions creating new classes are due greater honor because they likely are seminal in generating new areas of endeavor. They imply that inventor superstars are those that create new industry, and cite names like Goodyear, Morse and Stephenson as the essential catalysts for the Industrial Revolution. The transistor certainly fits that mold.
The figure shows the growth in total patents issued and how many are new codes (sub-classes) as opposed to combinations of classes. Note that the vertical axis is on a logarithmic scale. Whether an invention falls into a given class, say batteries or a sub-class say solar energy type (both real examples of classes), is determined by the patent office. So, to some degree, this point is a bit academic in that it relies on a judgment by these folks. Consequently, the determination to form a new class need not necessarily be the harbinger of great industrial activity. It could simply be because they could not find a place to slot it.
Possibly the greatest invention in the commercial practice of biology is the (1993) Nobel Prize winning Polymerase Chain Reaction (PCR). Some have described it in terms of biology having two epochs: before and after PCR. It allows the amplification of DNA sequences. This giant invention by Kary Mullis (incidentally a North Carolina native) nevertheless built on the work of others and in particular that of 1968 Nobel Laureate H. Gobind Khurana (in fact Dupont challenged the validity in a losing cause). It was an aha moment not unlike that of Watson and Crick in visualizing a double helix in the X ray diffraction images of DNA produced by Rosalind Franklin (who might have shared the 1962 Nobel had she not died of ovarian cancer in 1958). I seriously doubt it created a new class or sub-class. Yet it transformed a field of endeavor. I think we could conclude that a truly new class of invention may well be seminal, but that this quality can be achieved in combinatorial fashion.
On the matter of combinations, the patent office is very prescriptive on what constitutes invention. The granting of a patent requires two hurdles to be crossed: novelty and non-obviousness. One may build on the work of others but these two tests must be met. It is the second item that things get subjective. The invention must not be obvious to one of “ordinary skill in the art”. IP lawyers make a living splitting that hair. In the last few years the Supreme Court has raised the bar on this test. It has also raised it on what is known as enablement: the claimed invention must be described in sufficient detail so that a person of ordinary skill can replicate it. Gone are the days of “paper patents”.
This discussion would not be complete without noting that remarkable innovations may not be inventions in the legal sense. Innovative business models to capitalize on inventions are cases in point.
April 23, 2015 § 1 Comment
The price of oil is going to look like saw teeth for some time to come. For purposes of simplicity I will stick to using Brent, the benchmark price for the rest of the world. As I have opined before, if the US lifts the ban on export of our oil, WTI price will rise to Brent levels. These two benchmarks were in lock step for years and then began diverging in 2011 when shale oil seriously hit the market. While on the face of it simply a correlative point, I believe it is causal. When condensate exports began being allowed in 2014 the spread narrowed. I believe that when exports are permitted the spread will disappear altogether.
The graph shows Brent pricing up to late February 2015. Of interest is the fact that while the original drop was massive, nearly halving the price, the recent excursion is 25% off a new floor. True demand alteration is hardly ever that sudden. This is likely a result of real or perceived change in supply. Around that time Libya, which had fairly suddenly come on stream with 700,000 barrels per day (bpd) in late 2014, dropped to 200,000 bpd following sabotage and ISIS sourced violence.
On a go forward basis, the reason for price excursions will be real changes in shale oil production together with speculative beliefs in this regard. I have asserted in previous posts that the US has unwittingly become the swing producer, meaning when it sneezes world oil catches a cold. The Saudis used to have this status together with OPEC determinism of oil supply. Recently Boone Pickens shared a stage with former EPA head Carol Browner and ex-secretary of energy, Steve Chu, discussing the environmental safety of shale oil and gas production; no doubt the debate was entertaining. Associated with this occasion Pickens stated to the press that the US was responsible for the oil price crash, not the Saudis. While this is not exactly news to at least readers of my posts, I cannot recollect a causal link being suggested by any person vested with expertise. Most of the press has been on why the Saudis did it, rather than whether they did it. Damaging US shale oil production and hurting the economy of Iran and weakening Syria’s Assad (the latter through impoverishing financier Russia) were the principal theories advanced. Assuming the validity of Pickens’ assertion, one can conclude that if US production brought the price of oil down, then reduction in the same would send it back up. One theory of Saudi motivation would be supported.
Were the US production in question from conventional resources such as offshore development, one would not expect discontinuities. Conventional production has long latencies: many years to get going and it is not economically viable to turn off and on. Shale oil on the contrary is relatively easy in this regard. Producing wells can be “shut in” with relative ease, especially gas wells. Since these wells tend to decline rapidly in production, mere maintenance of rates in any given area requires drilling new ones. Simply not drilling new wells will have the net effect of reducing US production, which will in turn result in a rise in the price of oil. When the price is high enough they will begin drilling again. A new well can go on stream as soon as ten days after commencement. That period is even shorter for the over 3000 wells that reportedly are in “fracklog” bucket. This is a backlog of wells which have been completed all but for the final fracture stimulation step. Speculators are aware of this. They will drive price up when storage levels drop and the price has achieved a bottom of sorts. This cycle of price increase, new production then depressing the price, followed by reduction in drilling and production will repeat. The visual effect on a graph such as the one above is that of a saw tooth pattern.
Predicting the price of oil at any time is an exercise in futility. But my best guess at this time, based on continued weakness in China’s GDP growth, is that Brent pricing will fluctuate in the range $45 to $60 in the saw tooth pattern mentioned above. Whether OPEC can or will intercede in any way to affect this is not known. But it is unlikely that they will curtail production to raise prices. All that will achieve is more US shale oil production. I think the saw teeth are here for a while.
March 31, 2015 § Leave a comment
Not my usual blog. Just letting folks know that the site was down since March 16 due to a technical glitch. Even now you may get “certification warning”. Switch to Firefox or Bing or Explorer from whichever one gives the warning. Don’t ask why; I barely get by understanding these gremlins. Going to Firefox from Explorer did it for me. Sorry for the snafu.
February 24, 2015 § 4 Comments
My 2012 post High Octane has consistently had very high readership to this day. This merited a revisit. It is also a fitting topic on the heels of my last post regarding alternatives to petroleum based fuels being hurt by low oil prices. This price crash did more damage to that cause than just the already extended sojourn to the depths. It raised a specter that has always been in the psyche of oil old timers: the price can crash any time and it has in the past. In the recent past the dogma has shifted to volatility only north of about $90 per barrel. This was based in large measure on OPEC providing a floor and the juggernaut represented by the growing economies of China and India keeping demand pumped up. This last was bolstered by the well-known relationship between per capita GDP and car ownership.
Then the economic growth rates of China and India faltered. Furthermore, China started making a concerted push to use coal derived methanol as a gasoline substitute. India is experimenting with ultra-small cars such as the Tata Nano (70 mpg). Indian Prime Minister Modi recently lifted the restraints on genetically modified (GM) oil seeds. Rape seed oil (a variant is more conservatively named Canola) is expected to be an early beneficiary. Canola oil, ordinarily used for cooking, can be processed very simply into diesel with a process known as transesterification. In fact it is so simple that a garage operation would be quite economical. Also to be noted is that India consumes nearly three times as much diesel as it does gasoline, so oil seed conversion is advantaged.
But my favorite is Jatropha, which is indigenous to India, much of East Asia and Florida, for that matter. As I mentioned in a post two years ago, the time is right, and even more so now than when I wrote that piece. Jatropha created a lot of excitement in India and other places a decade ago because it was not a food crop and was drought resistant. The problem was that wild type jatropha was too variable in yield and other economically important parameters. Now with the plummeting in the costs of DNA sequencing, high throughput screening and associated data analytics a GM jatropha with great qualities need not be far away.
In some ways the foregoing discussion is something of a distraction from the premise of the original High Octane. There I suggested that ethanol, the legislative favorite displacer of gasoline, was not being properly utilized. Today Congress is seriously considering revising the flawed Renewable Fuel Standard. The principal flaw is the insistence on cellulosic ethanol, which has proved economically intractable. In today’s gasoline pricing scenario it is even more so. Technology simply has not kept up with congressional wishes and is unlikely to do so.
The biggest problem, however, is not that at all. It is the fundamental problem of trying to fit a round peg into a square hole. The two most viable gasoline substitutes, ethanol and methanol, will deliver 33% and 50% fewer miles to the gallon, respectively, in today’s conventional engines. These engines have been optimized for gasoline for a hundred years, which is why they have compression ratios of around 9. Higher compression ratios deliver more energy per gallon but cannot be tolerated by 87 octane gasoline. However, ethanol and methanol respectively have octane ratings of 113 and 117. A high compression engine will operate effectively with these fuel blends and give back much of the intrinsic energy penalty.
This is essentially a repeat of what I said in the last post. Now I have more ammunition to enable the substitutes. Both ethanol and methanol have one more very useful attribute that allows even higher compression ratios. They have high latent heats of evaporation. When injected into the cylinder the evaporative cooling effect reduces the temperature. This is a key because at high compressions the problem is temperature rise causing premature ignition of the fuel, also known as knocking. This cooling effect will enable very high compressions.
Now to the final point: is it asking too much of the automotive industry to modify the engines for higher compression? First of all race cars have high compression. But a more mass produced example just appeared a couple of years ago. Mazda introduced the Skyactiv engine which operated at a compression ratio of 13 with regular gasoline. The key step appears to be dual injection of the gasoline, the second one coming in response to temperature sensing and presumably producing evaporative cooling. This car is rated at about 35% higher highway mileage than the regular counterpart. One of the technology advances along the way has been to measure cylinder temperature and react to it. So they can do it if they want to.
Now consider the following facts. The cooling from injecting ethanol vapor would be about 2.6 times that from gasoline. A blend would be somewhere between and Mazda likely are getting a bit of that benefit with the 10% ethanol in most gasoline. And here is the kicker. With methanol that number is 3.7 times. So, even a 20% blend ought to give heck of a boost. Higher blends are completely feasible and China is piloting these, albeit in conventional engines. And methanol from inexpensive natural gas is more affordable than ethanol. Aside from the higher efficiencies, a cooler running engine produces less NOx. Also, a high compression engine delivers more torque. Such vehicles will be fuel efficient in the extreme, use less petroleum products, have vastly reduced tail pipe emissions compared to all but electric vehicles, and drive like muscle cars. They should move off the lot.
February 21, 2015 § 4 Comments
Sustained low cost oil will certainly damage the substitution of petroleum products in transportation. For the purposes of this discussion we will operate with the scenario that oil will hang around in the range $40 to $60 per barrel. But the answer to the question is more nuanced because oil is not oil. Different types of oil have differing carbon footprints and production costs. On the one hand, more cheap oil will inevitably lead to greater consumption and hence more associated carbon release. But what if the carbon footprint of the crude oil goes down, what then may be the net impact? We will discuss these matters below.
My position on oil substitution is essentially that of Ann Korin and Gal Luft in their book Turning Oil into Salt, substituting to the point that oil ceases to be a strategic commodity, and merely a useful one with alternatives. Prior to this oil price crash we were on our way albeit haltingly.
Status of Substitutes:
One entire class of substitutes was driven by arbitrage between gas and oil driven by per unit of energy price differential. This did not exist until about 2005 because both commodities were in lock step. In our assumed scenario the gap is still there, just closer to a factor of two than four in the US. The obvious casualties are natural gas conversion to diesel or gasoline. Sasol has already indefinitely postponed the Louisiana GTL plant. They would have struggled to be profitable at $90 oil. At half that they are in deep strife. Also, at a relatively constant $50 oil price US shale oil is essentially the swing producer, meaning ups and downs in this sector take the world price with them. In this scenario OPEC is essentially toothless and cannot be relied upon to be a stabilizing force on price. Nothing hurts a costly GTL plant with long amortization schedules more than uncertainty. With cheap shale gas in the US Sasol likely thought they had that licked. Then oil became low and uncertain and the wheels came off.
Less impacted will be gas to other liquids such as methanol and dimethyl ether. These are raw materials for a lot of chemicals and have world prices in their own right. Also, China is on a big push to substitute gasoline with methanol. Since that was driven largely by tailpipe emissions especially in urban areas, the reduction in the price of oil may not have as much effect. That could put a floor on the world price of methanol. Dimethyl ether is a seamless blend with LPG, a common fuel in countries such as India. Not yet commonly done, the lower hydrocarbon prices could slow down that thrust.
Direct combustion of natural gas in vehicles has had a lot of traction in the form of CNG in short haul and LNG in long haul applications. The narrowing of the oil/gas price will certainly reduce the economic merit of this action and consequently slow the momentum except in non-attainment areas and the like. The struggling passenger vehicle program will more than ever need technological advances in higher density and low pressure storage systems allowing economical charging in homes.
The challenge faced by widespread adoption of electric vehicles remains the same: battery prices south of $200 per Kwh are necessary. The next most important factor is reasonable night time pricing of electricity in all states. Gasoline prices matter, but not as much as the other two factors. The fact that electric vehicles (EV’s) are 60% more efficient well to wheel, and hence lower emitters of GHG (at power plants in their case) than conventional engines, ought to be recognized in policy setting. CAFÉ standard do not adequately take into account EV’s. At this early stage that is fair enough but a standard explicitly targeting emission reduction ought to recognize the unique EV advantage. The common challenge to EV’s is that they are only as clean as the electricity producing plant. The increased efficiency noted above means they simply use less energy no matter where it is produced. Furthermore, we are well on our way to at least solar power being cost competitive with alternatives in many markets without subsidies. Taken together with coal substitution by gas we can expect a gradual greening of electricity, certainly in the time frame that EV’s could reasonably be a double digit percentage of the market.
Consistently lower diesel and aviation fuel prices will reduce costs in the delivery of goods and of people. If this cost advantage is passed on it will increase commerce. Passenger vehicles will be driven more with low gasoline and diesel prices. CAFÉ standards will be harder to meet because the US public always switches to SUV’s and pickups when fuel prices drop. All of this and sheer increased commerce will add to the carbon burden.
What of the oil types and their carbon footprint? Canadian heavy oil is famously considered “dirty” by the folks opposed to the Keystone XL pipeline, meaning, that it has a high carbon footprint. This comes about in two ways. One is that this oil is intrinsically carbon rich compared to the hydrogen content. When refined it has a residue of carbonaceous material known as petroleum coke which is essentially coal with some differences. This can amount to up to 18% of the original oil. The second is that getting it out of the ground requires more energy than for recovering conventional oil. This energy use produces CO2. There is one other piece. Refining it requires a lot of heat to break down the big molecules. Considering all these factors it is a bit surprising that scholarly studies estimate only about 16% more carbon intensity when considering the “well to wheel” full cycle analysis. Part of the reason may be that so much of the emission is in the final combustion process no matter the source. One study has it as low as 6%. In any case it is more.
Prior to shale oil bursting on the scene, the marginal barrel of oil was getting progressively heavier. Even the more recent Saudi Arabian oil field Manifa is relatively heavy in character. The continued growth in oil consumption equated to more carbon release. Then came shale oil which is the polar opposite: very light and low carbon to hydrogen ratio comparatively. When shale oil is refined there is no need for high temperature molecule breaking processes.
Oil priced near $50, our scenario, results in a shift away from Canadian heavy oil provided enough of the light oil is available and can be produced sustainably. Canadian oil sands are exploited in one of two ways: Open pit mining and treatment of the oily sand and in-situ heating with steam to make it flow (SAGD). New mining operations break even at about $90 and are unlikely to be pursued. Paradoxically, already constructed mines are relatively cheap to operate if you don’t count amortization, in the vicinity of $25 per barrel operating cost, so current plants will continue to produce. SAGD breaks even around $65. Almost all future growth plans as far as I am aware are for SAGD, and this was even before the crash. Technology development continues to reduce the steam to oil ratios, which will help costs and carbon footprint.
Shale oil breaks even somewhere between $40 and $70. In our scenario the higher cost ones and those with restrictive financing will drop eventually. But the key point is this. These are early days in shale oil exploitation and technology to reduce costs is certain, it is only a question of timing. So, if the reserves are in fact there, North America will shift to a higher fraction of light oil and hence lower carbon footprint. But the original objective of chipping away at the oil monopoly of transport fuel still stands, while somewhat compromised by the low price on what it is substituting.