I've been thinking more about energy sources since oil was at $50/barrel . Since we reached the staggering heights of the last few months, I've been puzzling even more over what people will move to next.
Key to understanding this stuff is how much energy it takes to get your source in a useful form. A paper from the 1980's is illustrative: oil cost more than 10 times less energy to get from discovery to usable energy in the 40's than in the 70's. A lot of technologies barely broke even. If anyone has a newer version of this work, I'm interested.
For better or worse, I think you're going to hear a lot of chatter about coal liquefaction. The US has staggering amounts of coal - calorie for calorie, it works out to about as much oil as the Saudis have. A lot of our coal goes towards electricity, though, and this immediately raises a question - what happens to the price of coal? Then electricity?
We are in a weird situation now with electricity. Ten years ago a kWh of energy from gas cost three times less than a kWh of energy from electricity. Gas energy costs a little more than electrical energy today! If you figure gasoline has 130 MJ/gallon, and there's 3.6 MJ/kWh, you can convert a gallon of gas into kWh equivalents. Take a look at this graph comparing the price of energy from gasoline to energy from electricity (Source: US DOE, prices in nominal cents):
$4/gallon (not on the graph) gets you to 11.08 cents/kWh. For the first time ever, it's as cheap or cheaper to put energy into your car from the power grid than from the gas station. Of course, this neglects the source of the electrical energy, possible carbon taxes to come, the relative efficiency of the cars, and many other variables. But comparing electricity and gas in terms of kWh (or joules, or calories) brings the price ratio into sharp relief. If things get dire, substitutions that were previously deemed uneconomical might get a second look, and you may even see the Wall Street Journal refreshing its readers on what some of these units mean.
(Thoughts on my doing the occasional wonky post are welcome).
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You're comparing strawberries and grapefruit. The gasoline going into the tank is being counted before conversion losses; the electricity is being counted after conversion losses.
If we take 15% as the average net efficiency of a light-duty vehicle drivetrain (including braking energy as losses), electricity at 10¢/kWh is equivalent to gasoline at 54¢ per 130 MJ gallon. Add 50% to account for losses in chargers, batteries and motors and you're close to the CalCars claim of 75¢/gallon.
Thanks. I admit that I glossed over this and only gave it lip service in the paragraph after the graph ("relative efficiency of the cars"). I didn't realize the number was quite as low as 15% for gas cars, either, I figured they were both around half!
Then, there is another fact I don't mention: joule for joule, we use about as much gas as coal, and we comprise about 20% of world use for either. More electricity means more coal, all things being equal, and it's not like the coal market is a comparative juggernaut poised to easily take up the slack for gas. Any broadly-adopted EV technology will change the face of energy commodity prices.
After over 100 years of development, the very best production ICE car engines are only about 24% efficient. Compare that to the very cheapest electric motors at 33%, commercial electric motors at 90% and the record holders at over 99.9%.
Large power plants are 40-50% efficient. The US power grid 94%, plain old lead acid batteries 95% (slow charge) and electric motors 95%. It's easy to see that even before we add regenerative braking or consider the drastically lower pollution and maintenance costs we'd be better off burning the oil in powerplants and using electric cars. This does not require any new technology - only the will to do it.
My belief is that nuclear fission (fusion is way too unstable and inefficient still) is the way to go for large scale energy production, and hydrogen fuel cells for use in cars, the later producing no pollutants whatsoever.
I, for one, welcome the occasional wonky post. The net is overloaded with screeds and woo and apocalyptic rants about energy costs. Serious discussion, from an informed scientific perspective, is sadly lacking.
Without naming it you introduced the concept of EROEI Energy Return On Energy Invested. This is also decreasing for coal and natural gas, for much the same reasons as for oil, the easiest to exploit sources were tapped first. Coal prices have been rising faster than oil prices, especially of the metallurgical grade. Natural gas prices have been lagging oil lately, but observers note that the historical correlation between oil/gas price has been quite high.
I think gasoline ICE engines do considerably better than 15% efficient. However they only get their highest efficiency under relatively high load, i.e. when accelerating or climbing a hill. During low demand driving phases there are still very significant frictional losses (engine braking). Hybrids reduce this penalty somewhat as they intermittently shut off the ICE. Electric or NEV Near Electric Vehicles, have not been economical yet because of immature battery technology, not the relative cost of the energy. That is gradually changing, but cost of storage will be a significant limiting factor for the first generation of plugin hybrids.
I got the 14.9% figure via Odograph; here's the table and the source. I'd note that this figure only includes air drag and rolling resistance as useful work; energy dissipated in brakes is counted as a loss because it is potentially recoverable.
That's the bad news, agreed. The good news is, if all our vehicle production suddenly turned into PHEV's, the wind power added last year was sufficient to run a substantial fraction of last year's new fleet (~30% or thereabouts, depending on assumptions). Wind is on a steeply rising curve with a doubling time of less than 2 years, and it probably passed 1% of US electric generation last year.
In other good news, worldwide solar-PV production is on a similar doubling curve, albeit several years behind wind.
BTW, the Energy Information Agency's historical data is a treasure trove of information for checking out hunches.
So, what do we think is going to happen?
Europeans have long paid a lot more for gas at the pump than Americans have, thanks to higher taxes. Maybe we can get a rough idea of what Americans will do if gas prices continue to soar, by looking at what Europeans already do.
By the way, I do a mental backflip reading phrases like "three times less" and "more than 10 times less". I think journalists usually avoid such constructions. There's always some way to avoid them: for example, "a third as much" and "less than a tenth as much".
Once a society advances beyond a certain technological threshold, energy and currency will have the same units!
*jazz hands!*
As a chemist I always thought burning oil as a fuel was sin - there are so much more valuable, indispensible products that one needs to make from oil - chemicals, plastics etc. And it is not easy to make these materials from coal or other sources - and you would not want to see giant re-birth of coal liquefaction and calcium carbide technologies on the scale necessary to replace oil-based processes once oil shortages become more serious. So the high oil prices can be a blessing in disguise, and maybe we will be running the cars on vegetable oil or some fuel made with the help of electric energy or we will have elctric cables in the roads 30 years in the future and the oil could be saved for more important uses.
Before anybody enjoys a technowoodie from E*L*E*C*T*R*I*C cars note that Southern California will enjoy a historic number of blackout days this summer. SCE already knows its generating and importing capacities are wholly incapable of meeting demand as it continues to shift from nuclear and fossil generation to burning algae and other renewable alternatives. If any serious number of cars ran off the grid... you'd need a gasoline-powered generator to keep your refrigerator cold. ($100 off at Home Depot - we're not stupid.)
""Electric Cars: This does not require any new technology - only the will to do it.""
Actually hybrids and electric cars require new technology to be efficient. Or did. The big problem has been the power control for the electric motors. Before 1990 or so all solutions for controlling variable speed electric motors were either expensive, heavy, or unreliable. Fortunately in the early eighties the IGBT was invented. They allow huge huge amounts of electric power to be controlled reliably and at low cost.
http://en.wikipedia.org/wiki/IGBT_transistor
This is probably one of the most significant technologies that nobody has ever heard about.
The rolling blackouts will be during the peak A/C hours of the afternoon. EV's typically charge at night.
This is not to say that California can't use a lot more generating capacity, but the situation isn't as dire as some paint it.
Excellent book on this topic is "Big Coal" by Jeff Goodell.
Bottom line, yes there's a lot of coal left (300 years by some estimates), but the extraction is a giant mess, and is already wreaking havoc on the environment (mostly Appalachia). Mountain top removal fills in streams, leaves behind wastelands, poisons ground water, and just looks plain ugly. Is it really worth destroying one of the most pristine wildernesses in America for the sake of cheap energy? Another excellent book on the topic is "Lost Mountain" by Eric Reece - essentially an account of mountain-top removal over the course of a year - it is shocking, saddening, and downright scary.
This is before you even begin to consider the carbon costs of using coal. The infrastructure to deliver the coal to power plants is also aged and prone to failure. Goodell gives a great account of spending a day riding a coal train - 1 mile long with each car holding 10,000 lbs of coal. That's enough to keep a single coal fired plant burning for one day! Then consider that not all the coal in this country is nice clean hard black anthracite - much of it is dirty high-sulfur flaky coal.
The story of this country's future in coal based energy can be summed up as follows: "just because we can, does it really mean that we should?"