It all comes down to energy. Early in the day of the automobile the electric car was the simple, clean, quiet and reliable choice. It had more than sufficient power, but the batteries of the day could not store enough energy to compete with a tank-full of petroleum (or even alcohol). This turned into a killer deficiency. The electric was left driving short trips around town; gasoline offered range, all-day cruising, FREEDOM! Despite the pathetic 14.9% average efficiency of the US gasoline-powered fleet, a 15-gallon tank of gas can be turned into a whopping 82 kilowatt-hours to the wheels, yet it weighs less than 100 pounds and refills in a few minutes. A typical lead-acid battery pack for an EV weighs hundreds of pounds and holds less than 20 kWH, yet requires several hours to recharge. Clearly, something had to change before battery-powered vehicles could compete on the same turf.
Ever since the first Li-ion powered tzero showed that electric vehicles could overcome the range barrier, it was obvious that some battery technology would eventually make the EV competitive. The Li-ion battery with the lithium cobalt oxide (LiCoO2) cathode clearly wasn't it; cobalt is too expensive, it charges too slowly, and it releases oxygen when overheated which leads to destructive and hazardous thermal runaway. Besides, the $60,000 cost of a tzero full of 18650 cells was clearly beyond what the market will bear.
Several different chemistries are now vying for dominance. Valence Technology's Saphion, based on doped lithium iron phosphate, is made from very inexpensive materials and has no thermal runaway problems. Altair Nano has a number of products, some of which are meant for batteries; I understand that their lithium titanate is going into some fast-charging cells which also beat the thermal runaway issue and have excellent charging performance and cycle life. A123 Systems is cagey about their exact technology, but they've announced some power tools powered by their cells. Their cycle life is claimed to be good, and charge/discharge rate is stellar: 5 minute recharge, and discharge power almost up to 5 kW/kg. One of these appears bound to kick NiMH out of conventional hybrid vehicles; after that, the drop of price with increased manufacturing volume will lead to more and energy storage aboard vehicles. If this is combined with recharging from the grid, it will lead to less and less need for petroleum. It only takes one technology to cross the finish line to make it all happen.
Enter a dark horse to the race. a barium-titanate ultracapacitor. EEStor claims a unit with the following characteristics:
Reading this at The Energy Blog was another "HOLY CRAP!" moment for me. This is far cheaper than Li-ion batteries. Its energy density is comparable, the cycle life is far beyond the needs of a vehicle, and the power density is astounding. At a 10-minute discharge rate, I calculate the power output as up to 312 kilowatts. That's more than FOUR HUNDRED HORSEPOWER from a 400-pound package! If it can be drained in 200 seconds, it would out-power a Bugatti Veyron.
This product looks like it would make a killer EV all by itself, but it would also shine as the storage element of a GO-HEV. Suppose you could get a third of the capacity for half price: 17 kWh for $1600, weighing 150 pounds. It would drive a Prius+ about 60 miles, a somewhat larger car perhaps 45-50. If it let you eliminate 80% of a 750 gallon/year gasoline habit and replace it with $600 of electricity, it would save you about $800 a year at the gasoline prices I see.
Would you buy it? (You're reading this; do I really need to ask?)
If these things work as advertised, the first auto manufacturer to market them is going to see the fuel consumption of its products plummet. It would constitute a suit for divorce from the oil industry and everything else it is associated with. It could turn "electric" into synonyms for clean, quiet, safe, economical, and screaming performance. And peak oil? Who'd care? Overnight, oil would cease to be relevant.
A technology and a manufacturer. It only takes one.
I just lost 6 proto-posts and the beginnings of some verse in various stages of authorship due to a bus lockup. (Remind me to save everything before I start messing with the CD drive, just in case.)
Is this going to stop me? I've already pulled the titles from the post queue and built empty frameworks to start filling again. Won't get going tonight, but I have few doubts.
Blogging isn't a hobby, it's a compulsion.
Taking a long-overdue look at the Interstate system's statistics, I note that it has roughly 43,000 miles of roadway.
If we look at British estimates for cost and assume
$1.5 million/lane/mile $2.4 million/lane/mile for construction of rails down freeway medians, the entire Interstate system could get another 2 lanes of rails for $129 $206 billion. If overhead wires for electric power cost another $500 $800 thousand/lane-mile, the total rises to $172 $275 billion. This could potentially replace all truck diesel
used on expressways.
As of 2004, the transport sector was using 42.5 billion gallons/year (2.774 million bbl/day) of diesel. If 60% of this was burned on freeways, we'd have been able to save 1.66 million bbl/day; if the electrification of freeways allowed e.g. battery- or flywheel-powered operation for some local legs also, the total could go over 2 million barrels/day.
The total oil production of Iraq is now down to 1.7 million barrels/day. At $65/bbl, it's worth $110 million/day ($40.3 billion/yr).
If we'd spent the cost of the Iraq war on getting rid of our own petroleum demand, we'd have been able to pay for it at least once by now
, maybe twice. Ignoring the cost of maintenance and electricity, the savings would have paid back the cost in about 7 years at current oil prices. The return would be on-going, and boosted by reduced noise, smog and particulates. All we'd have had to do to Saddam is blow up his oil infrastructure so he had no money to buy weapons.
When I think about what we could have done versus what we did, it disgusts me.
UPDATE: Figures corrected for kilometers vs. miles (original erroneous figures in
strikeout where this displayed unambiguously). At least I wasn't trying to get this post to Mars.
I went to the EIA to get a reference for a figure, and found that the petroleum page was missing the link for historical data. I didn't see any links for the Annual Energy Review, either.
I spent some time poking around, and finally found a link to the data for historical electric data; from there I was able to construct the URL for the petroleum page and got what I wanted. But this should not have been necessary; the links should have remained in their usual places.
Is there an effort at the DOE to put our historical data down the memory hole?
(This one was worth a quickie.)
In a comment in "Treating irregularity", Marcos Dumay de Medeiros says this about direct-carbon fuel cells:
It annoys me a lot your insistence in making your calculations with the carbon fuel cell. It is experimental!
All right, for the sake of argument let us assume that the direct-carbon fuel cell scheme has some show-stopping problem and it's not usable. Not for vehicular power, not in stationary applications, not anywhere. If it doesn't work, what are the options?
Humor aside, when reality creeps in I am not one to bust it for trespassing. I always have a plan B, and in this case plan B is...
zinc-air fuel cells! (Tell me you didn't know that was coming. I won't believe you, but it'll be good for a laugh.)
Going back to Zinc: Miracle metal? for the chemistry, we pull these properties:
|Compound|| ΔH, gram
|ZnO (from zinc solid)||-84670|
|ZnO (from zinc gas)||-115940|
From a mole of carbon (93960 cal/mol), a mole of ZnO and an indeterminate amount of heat, we get a mole of zinc metal (84670 cal/mol) and a mole of carbon monoxide (68560 cal/mol) plus waste heat. Ignoring the waste heat, the 93960 cal of reactants yields 153230 calories of products. The question becomes, can these make as much useful output as a DCFC can make of raw carbon?
I believe so. Zinc metal is convertible to ZnO and electricity with an efficiency of roughly 62%, and CO can be fed to either a molten-carbonate fuel cell or a solid-oxide fuel cell; both can make electricity at an efficiency of roughly 60%. Here's what we'd get out of a mole of carbon via the two options:
|Reactant|| ΔH, gram
|CO||68560||SOFC or MCFC||60%||41136|
As long as you have a source of heat to drive the zinc reduction, you can get about 24% more total output using the zinc cycle compared to the direct-carbon system. There's a second fallback too: if neither the MCFC nor the SOFC are ready for widespread commercial use in time, carbon monoxide makes a perfectly good gas-turbine fuel. It can probably be converted to work as efficiently as natural gas, or about 55% in a combined-cycle plant. There's plan C.
Going back to dealing with irregularity, a carbon/zinc cycle helps in this way:
There's one more issue to deal with, and that's the dependence of the solar-thermal zinc reduction system (ZnO + C + Δ -> Zn + CO) on cloudless days. There just aren't many of those in some parts of the country that need energy. This is not a killer, because solar heat is just the sexiest source of energy to drive the reaction; it could just as easily be driven by surplus wind electricity (turning the immediate supply of wind power into two different storable fuels) or by combustion of part of the carbon (sacrificing the carbon monoxide byproduct). Either way, there's a reasonable alternative.
Does that address your objections, Mr. de Medeiros?
Update: ZAFC yield corrected in Table 2 (total was correct already)
The perennial complaint about the major renewable energy sources (and the lament of their users and advocates) is that they are irregular. If the sun shone all the time, you wouldn't need batteries; if the wind blew all the time, you wouldn't need backup generators; if it rained the same amount every day or even every month, you probably wouldn't need hydro dams and could make do with weirs and long penstocks. The grid manager can't schedule a one of them.
Unless all supply-demand matching can be handled by DSM, any system which depends on alternative energy is going need storage of some type. The devil is in the details, as ever. Availability of energy varies on scales of hours, days and even by the seasons; a collection system which is adequate on the average is going to be deficient at some times and produce large surpluses at others. There are loads which are well-matched to certain types of production (air conditioning vs. solar) but we aren't lucky enough to have all loads dovetail with renewable sources. Some kind of buffer is needed to split the difference.
Buffers on the scale of seconds to hours are available, in the works or proposed. Capacitors work well to buffer variations on the scale of milliseconds to seconds; flywheels are well-suited to smoothing differences lasting seconds to minutes, vanadium redox "flow batteries" have been suggested for handling time scales of seconds to hours, and compressed-air storage is being proposed as part of a wind-storage scheme. But only compressed air is capable of dealing with daily variations at reasonable cost, and none of the above deal well with variations lasting weeks to months.
Fortunately, a suitable medium seems to be available. Two, actually.
The classic stockpiles of energy are stacked firewood and heaps of coal. Oil is invisible by comparison; tank farms represent huge reserves, but they look the same whether full or empty and have no power as images. Yet not all classic energy is meant for the fireplace; food laid by is energy too, whether it is dried or salted meat, jars of food canned or pickled, roots in the root cellar, packed granaries, full silos or haylofts stuffed with animal fodder. Lately, fodder storage has expanded to square or round bales of hay kept either in or out of doors.
Fodder is biomass suited for ruminants. For combustion it needn't even be edible, just dry.
The favored energy crops these days are coppiced willow or poplar and various perennial grasses. The wet tropics produce good crops of sugar cane, but temperate zones are better suited to the likes of switchgrass or Miscanthus. The latter is reported to produce 25-45 metric tons per hectare per year1 with gusts up to 60. The temperate-zone grasses are particularly attractive because they die back to the rhizomes during the winter, and the stems left above ground become dry and easy to harvest. The standing crop represents stored energy. Once cut and baled, it can be stored on scales of days to months.
Baled grass is not an ideal storage medium. Its flaws include:
It would be best to convert the raw biomass to another medium: something waterproof, compact, more easily transported and stable over the duration of a year or years.
This medium exists. It is one of the oldest fuels known to man: charcoal.
Charcoal is the solid product of the slow anaerobic pyrolysis or partial combustion of most forms of biomass. It is so stable that it is used for radiocarbon dating of prehistoric human activities. Aside from its friability, it is as storable as coal and can be handled in similar ways. It contains little or no sulfur or heavy metals, burns much more cleanly than coal, and is usable as a substitute for coal or coke in many processes.
As I've noted before, the conversion of biomass to charcoal loses roughly half of its stored energy as heat and combustible gas. The presumed 1.3 billion (dry) tons of available waste biomass has a total energy of 20.8 exajoules (19.7 quads) at 16 GJ/ton. This is over 3 times as much energy as the natural gas used for electricity. At an average productivity of 35 tons/ha for Miscanthus, each additional million hectares devoted to biomass production would yield another 560 PJ (0.53 quads). Of the ~32 million ha devoted to maize alone, perhaps 10 million could be converted to Miscanthus as part of a price-support program. This might yield in the neighborhood of 5.3 quads of fuel, for a total of 24 quads of biomass. Other conversions might add to this.
Once you've got the biomass, the question becomes how to manage it for the greatest benefit. Some of the options are flexible, but are linked to cycles which are not terribly efficient. For instance, the production of bio-oil by flash pyrolysis yields about 70% of the mass and energy of the input as oil; the rest becomes char or gas. The bio-oil is suitable for boiler or perhaps gas-turbine fuel, but the net efficiency is low (if fed to a 35%-efficient steam plant, 24.5%; if fed to a 40%-efficient gas turbine, 28%). On top of this, it does not store well. It appears likely that charcoal will soon be convertible to electricity at 80% efficiency using direct-carbon fuel cells; maximizing the production of charcoal appears to be a good strategy.
Processing ~1.6 billion tons of biomass through a carbonization step which turns 28% of it into charcoal would yield ~450 million tons of charcoal. For the purpose of this analysis, I'm going to assume that the charcoal is not typically used to produce electric power for the grid. Some of it goes to mobile DCFC's aboard vehicles, replacing petroleum fuels in internal-combustion engines; an average demand of 183 GW would require approximately 220 million metric tons/year of charcoal for vehicle fuel. The remainder could go for chemical production, metallurgy, strategic stockpiles or just to be sequestered. For whatever reason, it's the last (renewable) choice for grid power.
If the carbonization process loses about 52% of the energy in the raw biomass, it seems prudent to use it well and wisely. Charcoal stores well, so the carbonization could be scheduled to produce gas when needed. If the heat and gas can be converted to electricity at efficiencies typical of simple-cycle gas-turbine powerplants (say, 40%), the recoverable electricity from the waste biomass would be 4.33 EJ (1200 billion kWH) with another 116 petajoules (32.4 billion kWh) from each million hectares converted to biomass crops. This is an average power of 137 GW from the base amount of biomass and a further 3.7 GW from each million hectares converted; for the case of 10 million ha converted, the average available electric power from carbonization would be 174 GW.
The average US electric consumption in the year 2004 was roughly 450 GW. An average power of 174 GW is over 38% of the total. Could this fill the gaps in other renewable supplies? The answer appears to be "it might, depending". I have neither the time nor the data to do a comprehensive analysis of the adequacy or lack thereof, but just to try to get a feel for it I'll guesstimate this by geographic area.
The following includes a certain amount of hand-waving. You have been warned.
In the south and southwest, air conditioning accounts for a very large fraction of the total electric consumption. The peak demand coincides with sunny conditions, so it seems that solar might well suffice for half of total electric requirements there. The use of ice-storage systems would allow a day's production to carry cooling demand overnight, eliminating the need to generate or store electricity for the purpose. Solar could also be used to meet other power requirements during daylight. How much is that? As an educated guess, half seems reasonable. Adding 38% from carbonization leaves only 12% to be met by other sources. Nuclear already accounts for 20% of total US electric production, so that seems to be taken care of.
The midwest is a fairly windy place. The windiest sections are also among the least populated, but HVDC transmission may go some ways toward bringing supply and demand together. The total amount of wind power potentially available is enormous; it is large even compared to total 2004 US consumption of 3953.4 billion kWh. Per this list, the wind power from the top 20 states could meet this fraction of total US electric demand:
|Fraction of 2004
Of the top 10 states, I would put only Texas, Montana and Wyoming outside the Midwest; the remaining 7 have a potential of 6,111 billion kWh/year, or 155% of 2004 US consumption. There's clearly enough energy there to do most anything we want.
Unfortunately, the availability does not coincide with the times we want to do it. Wind has a capacity factor of about 30-40%; it may be feasible to use wind to meet more than that much demand using storage of ice and hot water, but it's not obvious to me without information I don't have right now (if demand is phased opposite to supply it could be less). Still, if wind can handle 40% of demand and biomass carbonization can take care of 38%, the remaining 22% is very close to what's currently met by nuclear.
California, Oregon and Washington are problems. California has 10% of the US population, but it ranks #17 for wind-energy resources and its potential is only 1.5% of US consumption; outside the sunny southern part of the state its renewable resources don't look good. Oregon and Washington aren't even on the list. Idaho's population of 1.4 million (~0.45% of US population) might be able to export much of the 1.8% of US consumption that its windpower represents, but that would easily be consumed by Washington alone.
Together, Washington and Oregon have approximately 7.8 million people, roughly 2.6% of the nation's population. They are also major exporters of forestry products, and would be equally major sources of the biomass needed to power this scheme. They might be able to capture a fair amount of their needs with hydro projects. 2.6% of the US's electric consumption is about 103 TWH/yr; if 38% of this comes from carbonization gas, 30% from imported wind and 20% from nuclear, the remaining 12% could come from a combination of nuclear and hydro with some extra available for export. The exports might meet the remaining demand of northern California, or they might not.
The oceans might fill that gap. The Pacific has considerable wave energy potential, and the wind between 5 and 50 miles off the east and west coasts might produce as much as 900 GW. Unfortunately, the technologies for tapping this power are just being developed.
The East is in somewhat of a pickle. On-shore wind resources are not great, they are far from the windier parts of the country (HVDC transmission might help, if opposition to transmission lines can be overcome), conditions are often cloudy compared to the less-humid West, and the dense coastal populations don't have anything like the per-capita biomass resources of the corn belt or PNW rain forests. Only Maine hits the top 20 list for wind resources, at #19.
There are a lot of people to be served there. The combined populations of New York and Florida alone are about as much as the west coast states; adding in MA, NJ, MD, VA, NC, SC, and GA brings the total to 86.3 million, or almost 29% of the total population. Wind and wave energy from the continental shelf might also address this deficiency, but we don't even have a significant test program in place for such devices, let alone a plan for installing sufficient capacity.
If the East has to get 30% of its electricity from something outside the set of (nuclear, solar, wind, carbonization) it might be a reason to tap that 230 million tons/year of carbon I set aside above. If the east accounts for 29% of total US electric consumption (~1150 billion kWH out of 3953.4), direct carbon fuel cells could produce 30% of that using about 47 million metric tons of carbon2. This is about 20% of the possible set-aside, and appears well within reason.
A system based on biomass cycles lasting months and carbon storable on a scale of years addresses the irregularity of wind, solar and hydro. The quantities available appear more than sufficient to fill in missing average supply, and it appears likely that it can be scheduled to cover immediate shortfalls. A more detailed analysis will be needed to determine the specifics.
The next thing to notice is that it appears feasible to use renewable carbon burned in DCFC's to replace all vehicle fuel3, and wind, solar and carbonization gas to replace all coal and gas burned in electric powerplants. Getting the job done completely probably requires off-shore wind/wave energy harvesting plus solar energy systems on a scale never seen before, but all of these technologies are under development and even being installed on a pilot scale. About 4.8 billion barrels/year of petroleum products, 6-some quads of natural gas and a billion tons of coal would be surplus.
The impact of petroleum reductions alone would be huge. The US balance of payments deficit for some years ran roughly equal to the value of petroleum imports. Eliminating the demand from motor vehicles would cut a fraction roughly equal to US imports; other petroleum needs might be replaced by materials derived from the biomass processing. The replacement of coal mining by grass cutting would eliminate many dangerous underground jobs and also many open pit mines and spoils heaps. The mining jobs would be replaced by industrial and service jobs building, maintaining and operating the wind, solar and biomass systems. The almost inevitable result is that the dollar would rise, and so would wages. This translates to higher standards of living for millions.
Wind, solar and biomass would replace about 28 quads of petroleum, 6 quads of natural gas and perhaps 25 quads of coal. Some of these would be replaced by wind, solar or biomass-derived charcoal. As much as 230 million tons/year of charcoal would be kept back from mobile use. This charcoal could be devoted to uses (e.g. soil amendment to retain nutrients) which sequester carbon, or used in stationary industrial processes which allow the carbon to be captured and stored. Properly executed, this would allow the system to be strongly carbon negative.
The following would be largely or wholly eliminated:
Conclusion: to a first approximation, this is doable. If it's doable, it's highly desirable.
 Personal communication, Emily Heaton, assistant to Professor Steven Long, UIUC. (back)
 Calculated as follows: 93960 cal/mol heat of combustion, 12 g/mol = 7380 cal/gm, 4.184 J/cal produces 32761 J/g or 9100 kWh/tonne. 80% efficiency produces 7280 kWh/tonne, so the production of 345 billion kWh would require ~47.4 million tonnes of carbon. (back)
 Plug-in hybrids could replace a great deal of the vehicular charcoal consumption with electricity consumed directly; the charcoal would become available for industrial use or grid power. (back)
In an NYTimes piece that's not freely available on-line (but summarized by WattHead), Thomas Friedman shows that he's gotten with the program. Some excerpts of excerpts:
Sorry, but being green, focusing the nation on greater energy efficiency and conservation, is not some girlie-man issue. It is actually the most tough-minded, geostrategic, pro-growth and patriotic thing we can do.
Living green is ... a national security imperative.
... there's a huge difference between what these bad regimes can do with $20-a-barrel oil compared to $60-a-barrel oil....
We need a persident and a Congress with the guts not just to invade Iraq, but to impose a gasoline tax and inspire conservation at home. That takes a real energy policy with longterm incentives for renewable energies - wind, solar, biofuels - rather than the welfare-for-oil-companies-and-special-interests that masqueraded last year as an energy bill.
Large chunks of this could have come out of Petroleum independence as a growth engine. I doubt that Mr. Friedman read it, or has even heard of this blog, but it shows how far these ideas are starting to penetrate.
I would be thrilled if he'd paid any attention to me, but it doesn't matter. There's a positive vision opposed to the oil interests represented by Bush and Cheney. People who read nothing more technical than the NYTimes editorial page are learning that we can do more than just pay money to terrorists for the privilege of driving. We might do something about our deteriorating balance of payments and take power away from corrupt elements world-wide. Damn, that feels good!
I just received notice that I've been RedOrbited, or whatever you call it. RedOrbit readers, welcome.
You will find the post that RO quoted here: Immediate responses: Revive the PNGV
You might also like to browse these posts:
Read. Enjoy. And follow the link to SinceSlicedBread, register and vote for me Monday if I make the finals. Please?
The Google ads are like a free-to-you tip jar. But there's bigger stuff out there.
As most of you know, I entered a concept in the SinceSlicedBread idea contest a few months ago. They are about to post a list of the finalists, which the public will then vote for. The winners get substantial cash rewards - and the voters don't pay for it, the SEIU does. It's another free-to-you tip jar.
But to vote, you have to be registered there by Monday. If you haven't already, I recommend you go there and do it. It gives you a chance to bestow some mighty big kudos on somebody.
While I'm trying to get the amount of hand-waving in the "Irregularity" essay down to sane levels (I don't want to pick on other people for making vague, unsupported statements and then make a hypocrite of myself), I am also thinking about what to write about next.
There are at least three mega-engineering concepts I've been noodling about. Parapundit touched on one (aerosols) the other day; the other two are orbital sunshades and ultra-large convection towers. I'm not sure how much time it would take to finish a treatment of any of these, but given a choice, what would you like to see?
This is so funny I just had to quote it:
Zippy: Griffy, does th' SUN circle th' EARTH?
Griffy: Nope, other way around!
Zippy: Does th' MOON emit its own LIGHT?
Griffy: Nope, reflects th' SUN'S...
Zippy: Then I've based my whole FAITH on several FALSEHOODS!
Griffy: That's th' way the DOGMA crumbles, Zippy...
Zippy: But without NUTTY BELIEFS, th' sales of many best-selling BOOKS would PLUMMET!
Griffy: Really bad writing ALONE cannot explain th' success of "THE DA VINCI CODE"!
Whoever's been clicking on the ads today has made New Year's Day relatively profitable. Nowhere near minimum wage for the amount of time I've been writing, but appreciated nonetheless.
If you want to think of that link as the tip jar, go right ahead.
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