"An economist is an expert who will know tomorrow why the things he predicted yesterday didn't happen today." "Nimblefinger" at xkcd forums

## Saturday, January 18, 2014

### Your share of the world | Grist

'via Blog this'

A fascinating perspective on available resources and what I've referred to as "self-poisoning." While the credit at the site is given to "Grist Staff," it was actually written by my college friend Dr. Michael Tobis, who now edits the Planet3.0 web site.

## Saturday, January 11, 2014

### MPGe?

The Nissan Leaf is rated by the EPA to achieve a so-called "MPGe" (miles per gallon gasoline equivalent) of 129 city, 102 highway, and 115 combined (note that the EPA sticker to the left is for an earlier year of the Leaf, I couldn't find a 2014 version). What is this "MPGe" of which they speak? While the linked Wikipedia article gives a thorough explanation, I want to briefly cover a couple of aspects.

First, the EPA makes the assumption that a gallon of gasoline is equivalent to 33.7 kWh (kilowatt hours) of electrical energy. In a straight comparison of chemical potential energy to electrical potential energy, this is accurate to within the variability of the myriad blends of gasoline available. The energy content of various fuels is listed here (though not in units I prefer).

I pay $0.16/kWh, so the 33.7 kWh would cost me$5.39, whereas a gallon of gasoline (I bought 8.6 of them yesterday) would cost me $3.639. On the other hand, that gallon will take me a trifle more than 50 miles whereas the 33.7 kWh will (by the EPA's reckoning) take a Nissan Leaf 115 miles. And my driving habits enable me to better the EPA rating of 42 m.p.g. for my car by about 21% so I might be able to drive the leaf 140 miles. Thus, I spend about 7.1 cents per mile for energy in my CT200h versus the 3.8 cents/mile I might spend in a Leaf. What gives? The fact is that the battery to electric motor to driving wheels efficiency of the power train in the Leaf is going to be close to 90%, while the fuel to heat to mechanical motion to wheels in the internal combustion engine will be well under 30% on a good day. Over 70% is exhausted to the environment as waste heat. It must be kept in mind that, neither in the EPA sticker ratings nor in my calculations for my car, is the energy used in getting the battery or tank filled included. That is, the energy to generate and transmit the electricity and the energy to extract crude, refine it to gasoline, and deliver it to the gas station is not included. It counts only what's in the vehicle. Supposedly, the CAFE ratings DO utilize the so-called "well-to-wheel" efficiency. There's a very nice comparison (albeit written by Tesla employees but still very credible) of the well-to-wheel efficiencies of a few examples of internal combustion engine vehicles, hybrids (non-plug in) and the Tesla battery electric vehicle here. The Tesla is about twice as efficient as a Prius on that basis. And DAMN those Tesla Model S roadsters look good! ## Sunday, January 05, 2014 ### Convert my CT200h to plug-in? My Lexus CT200h is EPA rated to get 42 miles per gallon combined. In it, over the 2 1/2 years I've had it, my total net has been 51.0 miles per gallon. The CT200h has a hybrid power train with a 1.4 kWh (kilowatt hour) NiMH (nickel metal hydride) battery. This battery is good for a mile or so at very low speed in so-called "EV mode." Plug-in hybrid electric vehicles (PHEVs) will have much larger batteries, enabling them to travel further and faster in EV mode. For example, the Prius PHEV is estimated to be able to travel 11 miles and at a maximum EV mode speed of 62 m.p.h. It achieves this with a 4.4 kWh battery pack. And the Chevy Volt now sports a 16.5 kWh battery pack that is estimated to provide an EV mode range of 38 miles. I wondered if it would be possible to install a larger battery back and charging capability to my CT200h to convert it into a PHEV. As it happens, the answer is yes. And a huge variety of installations are possible, all the way from 2 kWh to 15 kWh capacity. Note that the Nissan Leaf, a pure electric vehicle (EV), sports a 24 kWh battery pack and a claimed range of 75 miles. Should I install any conversion and, if so, which one? This can be looked at from an economic viewpoint and from a CO2 emission viewpoint. I'll look at both. As a baseline, my most common drive is the daily commute from my home in Anaheim Hills to my office in Long Beach. This round trip is about 62.5 miles and I do it, on average, four times each week. I'd be able to charge the vehicle at work, though I'd have to park at our laboratory facility about two blocks from our corporate offices. Such a strategy would enable me to utilize a battery pack with a 35 mile range to, on a typical day, never have to use the internal combustion engine. What would this look like? The 7 kWh pack theoretically provides this 35 mile range, and I'd assume it would do so by discharging no more than 90%, but let's be conservative and assume that I'd need 14 kWh of charging per day. Assuming the charge system is 85% efficient, I'd draw about 16.5 kWh from the grid. At$0.16/kWh, this would cost about $2.64. I'll round down to$2.50 because I don't really quite go 70 miles on my daily commute.

Currently, with my 51 m.p.g. average, I use about 1.22 gallons of fuel in my commute. At a current price of $3.699/gallon, this costs about$4.50 per day. Thus, the conversion would save me something like $1.86 per day and, for 200 trips per year, I'd save$372/year. It's not completely clear from Plug In Supply's pricing page but it looks like I'd pay $9,875 for the 7 kWh system fully installed. Clearly, from a purely financial point of view, this makes no sense. As to CO2 emissions, this is a bit more problematic to compute. I'd be getting half of my electrical energy from our house, where the City of Anaheim provides our electricity, and the other half in Long Beach, where Southern California Edison is the provider. And, assuming that some combination of coal, nuclear, and natural gas provides almost all of the electricity, I won't figure in emissions resulting from extraction and transportation of these fuels. This is reasonable, I'm not figuring the emissions resulting from extracting, refining, and transporting the gasoline I burn. The calculation for the CO2 emissions from burning 1.22 gallons of fuel can't be exact as I don't know how much ethanol is in the fuel, and the mix of the various hydrocarbon chain lengths. I'm going to assume that the gasoline consists of n-heptane, C7H16 at that its density is 6 pounds per gallon. The chemical reaction would be C7H16 + 11O2 → 7CO2 + 8H2O. A mole of heptane has a mass of 100.2 grams. This mole results in 7 moles of carbon dioxide, each with a mass of 44 grams for a total of 308 grams. Now, I'll be a bit general and figure that I use 1/51=0.0196 gallons of gasoline per mile. This gasoline weighs 0.118 pounds or 53.4 grams. This produces (308/100.2)*53.4 or 164 grams of CO2 per mile (this is the typical metric for vehicular carbon dioxide emissions) for a total on my commute of 62.5*164=10,250 grams or 10.25 kg of CO2. That was the easy part. The electrical emissions are much more problematic because I've not been able to determine the mix of sources for Long Beach electricity. I'll just speculate. In any case, I need to determine the emissions related to 7 kWh from the City of Anaheim and 7 kWh from Southern California Edison in Long Beach. I'm not able to find the appropriate mix of generating facilities to use to calculate for Long Beach, so I'll back into it from information from California State University Long Beach on this page, where it's stated that the renewable generation of 656,000 kWh avoided the emission of 471 metric tons of carbon dioxide. CSULB is only a couple of miles from our office, so this will have to suffice. So the generation of 7 kWh would involve the emission of 8.25*(471,000,000/656000) or 5,923 grams of CO2. From Anaheim, I'll use the figures from my previous post on the Nissan Leaf. Using those numbers (and sparing my readers the gory details) I can figure that those 8.25 kWh involve the emission of 9,051 grams of CO2. The total emissions are thus 9,051+5,923 or 14,974 grams of carbon dioxide. Call it 15 kg. This is half again as much as my CT200h emits burning gasoline and the main culprit, as was the case for the Nissan Leaf I looked at, is that the City of Anaheim derives a surprising amount of its electricity from the burning of coal. And this information comes straight off of our bi-monthly bill! So, when all is said and done, it makes no economic sense, and certainly no sense with respect to CO2 emissions, to undertake such a conversion. That's comforting because I don't have a spare$10K to throw at such a project!

And all of this probably overestimates the gains. The careful reader may have noticed that the Chevy Volt uses a 16.5 kWh pack to go 38 miles or 0.43 kWh/mile. The Nissan Leaf uses a 24 kWh pack to go 75 miles, or 0.32 kWh/mile. The Plug-In Supply site, where I got these figures, claims 35 miles on 7.33 kWh or 0.29 kWh/mile. It's true that these figures represent a Prius rather than a CT200h but I'm skeptical that the Prius is that much more efficient in terms of aerodynamics and rolling resistance than a Chevy Volt or a Nissan Leaf.

## Friday, November 29, 2013

### Ack! ANOTHER "capture the energy of walking/driving" system

I really don't want to turn this blog into a debunking site but some things just must be said. Here I described a completely impractical system for "capturing energy from pedestrians." And now we find an article from Science Daily about Mexican entrepreneur Héctor Ricardo Macías Hernández, pictured at left, who's developed yet another system for capturing energy from passing traffic - vehicular or pedestrian.

It apparently consists of a traffic wearing surface that sits five centimeters above street or sidewalk level. Passing traffic squeezes a bellows, compressing air into a tank (the linked article says "...where it is compressed..." but I don't imagine that that's accurate) from which it is expanded into a turbine to generate electricity.

Think about it. Your engine (either that of your vehicle or of your metabolism) is squeezing air into a tank. This work will reduce your gas mileage (or use your food energy) as your vehicle or your feet do the work of compression. There is no free lunch here. I'm surprised to see it in Science Daily which, although it is sometimes prone to exaggeration, usually doesn't publish nonsense.

There are no figures given, either in the Science Daily article or the articles linked from there, so I don't know what kind of traffic would be claimed to generate what kind of power. But I do know that, whatever the amount generated, it would be more efficient to burn natural gas in a turbine. Both vehicular internal combustion engines and human metabolisms are inefficient and compressing air is a lossy process. I'd love to see figures for this but it's yet another candidate for my prospective Greenwashing Hall of Fame. Yes, I know that the term "greenwashing" is typically applied to deceptive ad campaigns but I think it's equally applicable to deceptive products.

Update: In thinking about it, I suppose that one could concoct a scenario wherein a developing country with few energy resources would rather have the "rich" who own cars spend some of their energy (i.e., gasoline or diesel) purchase on providing energy for township than purchase natural gas, oil, or coal and then charge the poor residents for the electricity or pay for the fuel with taxes. But even there, better a gasoline tax with the proceeds used to pay for more efficient energy generation.

### Solar panels on a truck?

I took my family to the LA Auto Show yesterday. Despite studies and articles contending that young people today are not so attached to automobiles, my son is absolutely captivated by them. He knows the makes and models, what he'd like, how he'd modify it, etc. I knew he'd have a great time and he did. I wanted to see developments in electric vehicles, plug-in hybrids (PHEV), etc., both production and concept.

I noted a pickup truck with a tonneau cover consisting of a solar panel and wondered about its practicality. Neither the Via Vtrux pickup (a series PHEV) nor the SolTrux panel option are in production, which is anticipated for 2014. It's a nice looking truck.

But is the solar panel practical? I have a Jeep pickup into which I've installed a 32 gallon water tank and other items designed to let me be self-sustaining in the Mojave, Sonoran, and Great Basin deserts of the Southwest. Where better to capture the sun?

So what are the appropriate numbers? We'd like to have battery capacity, dimensions and efficiency of the solar panels, and the claimed output. Here we find that the battery pack is 22 kWh. The dimensions of the panel array aren't given. but the standard bed is 78.7" long. The width isn't given but might be 65". The larger panel is stated to be 800 watts.

I see here that, in March (about average) I can expect on the order of 5 kWh/(m^-2*day) (kilowatt hours per square meter per day) for a panel mounted horizontally as it would be on a tonneau cover or roof rack. If I assume that the panels are 72" X 60", or 2.8 m^2 they should intercept 2.8*5 14 kWh per day. At 20% efficiency, I should get (surprise) 2.8 kWh/day. Assuming that I'd never let the battery pack below 20% charge, it would take 17.6/2.8 or a bit over 6 days to fully charge the battery. And the 22 kWh is represented to be good for 35 miles (though my desert miles are VERY hard on energy use). At that ratio, a day's worth of sunshine would take me (2.8/17.6)*35 or about 6 miles and probably a lot less in the rugged terrain where I'd be operating.

I suppose that, were I (through incredible stupidity or possibly a punctured fuel tank) out of gas and stranded, I could drive six miles per day for however many days it took to get to civilization (a very long way from the places I go). The fact of the matter is that it simply takes a lot of square meters to provide significant power. Verdict? NOT worth the estimated \$3,000 price for the panels.

Update: Here's a clickable link to the article cited in the comments by Anonymous.

## Saturday, November 23, 2013

### Embarrassed to be conservative - a (sadly) continuing series

And yet, within MY definition and one that I will defend, I still am.

'via Blog this'

### A digression - should interest in sci fi be a qualifier for gifted programs?

Since my blog muse has, hopefully temporarily, abandoned me and my calculations regarding the energetic plausibility of carbon dioxide sequestration via carbonate minerals is taking much more time and effort than I'd anticipated, I'm going to go completely outside any subject space I've dealt with.

As a youngster, I read a LOT of Isaac Asimov's writing. While Asimov is very well known for his science fiction, I read none of it. What I read were his essays, which covered such an amazing breadth of topics that it's hard to believe that a single individual could do it. However, one that I read rankled.

Asimov was clearly a prodigy and, back in my youth, some regarded me as such. All that ever interested me was science and math and I was fortunate enough to attend a progressive (in the academic rather than the political sense) school. I was accelerated, I was offered training in scientific investigation, and I was offered the opportunity to choose what I studied, at least to an extent (I managed to squander most of this advantage upon reaching college but that's a story for another time).

But Asimov wrote an essay (I can't find it but remember it distinctly) suggesting that school children be assessed for accelerated learning or "gifted" (a label sometimes applied to me) programs based on their level of interest in science fiction. I found it then and find it now to have been pretty self-serving and self-aggrandizing for such an otherwise objective thinker.

I started both Asimov's "I, Robot" and his "Foundation" series and finished none of the stories, finding them much less interesting than reading and studying science and mathematics. I could likely count the science fiction stories I've read on the fingers of a hand (and I wouldn't need the thumb). I read "The Hobbit" and found it quite boring, and made it through two and a half of the "Lord of the Rings" trilogy (at Northwestern University in the early '70s, at least in my circles, it was a scarlet letter offense not to have read these - I had a fraternity friend who prided himself on reading the entire trilogy every year). Halfway through the third novel, I concluded that "this sucks, I'm reading it only because I'm supposed to" and put it down, never to complete it. Yes, I realize that Tolkien's works are fantasy rather than science fiction but I'm sticking with the point.

What point is that? It's not really clear, but it's a rant I've kept inside for decades. The trailers for "The Hobbit - The Desolation of Smaug" are popping up and brought it to mind. I've not seen any of the previous Tolkien adaptations (for the matter of that, I saw the original "Star Wars" in 1977 and have seen none of the prequels or sequels). I did watch all of "Star Trek" and some "Star Trek TNG" so I guess I'm not completely immune, but these shows could almost as well have been done as westerns!

In any case, I'm not at all sure that Asimov's razor (as I'll call it) would be the appropriate metric for determining the suitability of elementary school students for gifted programs (assuming such programs still exist in this day of No Child Left Behind-based teaching to the test). I'm sure it's a reflection of both my ego and my ability to hold a grudge that an essay I read, probably, over 40 years ago still causes resentment but perhaps this post will allow me to finally let it go!

## Saturday, November 02, 2013

### Sterling Allan's "Aviation 2.0"

 Image credit: peswiki.com
I've frequently been critical and even sarcastically critical of Sterling Allan and his endless credulous touting of "free exotic energy" schemes and buy-in to every tin foil hat conspiracy theory out there (9/11 truth, Obama birther, chemtrails, "disappearing" of energy innovators, ad infinitum) and I'll likely continue to be so. But just because Sterling believes it, it isn't necessarily false.

Allan is now engaged in promoting, both on his multitude of sites and on the crowdfunding site indiegogo, what he represents to be an amazing breakthrough in internal combustion engine technology.

The concept being discussed is the "MYT" ("Massive Yet Tiny") engine, invented by Raphial Morgado. The specifications are impressive, particularly with respect to delivered power to weight ratio and the workings of the engine are clever. Below is an animation.

A hand-cranked mockup from the Los Angeles Auto Show makes the workings fairly clearly:

Because each piston fires twice in each crankshaft rotation and there are four pistons on each of two disks, there are 16 power strokes per crankshaft rotation. And the key to lots of power is burning lots of fuel in a short amount of time.

In this lengthy article, Allan gives a fair amount of information and a couple of documents comparing the MYT to existing ICE (internal combustion engine) technology. In particular, I'd like to look at the Angel Flight PackTM. This implementation is claimed to enable the "jet pack" capabilities that have been spoken of for decades and whose success has been marginal at best. The impediment has been the need for large amounts of fuel and a heavy engine limiting the flight durations to seconds rather than hours or even minutes.

Below is a comparison spec sheet from Morgado between his Angel Flight Pack and the Martin Jetpack (possibly the most highly developed such device):
The key figures are fuel burn at 3 gallons per hour (vs. the 10 gph of the Martin Jetpack) and the fuel capacity of 1.5 gallons (vs. the 5 gallons of the Martin Jetpack), the gross weight of 290 pounds (vs. the 533 pounds of the Martin Jetpack), and the engine weight of 25 pounds (vs. the 125 pounds of the Martin Jetpack). Maximum thrust for each engine is quoted as greater than 600 pounds.

So, with my 170 pounds (coincidentally the precise weight of an FAA "average adult") plus the pack, the takeoff weight is 170 pounds of payload plus 9 pounds of fuel and 25 pounds of engine, totalling 204 pounds. This is 86 pounds below the gross weight, I'm good to go. Even if I carry 25 pounds in some sort of bag, a flight suit, and a parachute, I'm still good to go. With this, Morgado claims that I can travel 100 miles at an altitude of 5,000 feet and (elsewhere in the article) a speed of 62 m.p.h. Interestingly, elsewhere in the article, Allan quotes 45 pounds for the engine weight.

There's no indication of the nature of the flight controls, but I assume that it's some combination of body position and thrust vectoring. Let's see what we can figure out. The basics of straight and level, unaccelerated flight are: thrust=drag and lift=weight. Using the usual numbers for Cd, and the other pertinent factors, the drag force can be calculated as about 259 Nt or about 58 pounds. Lift will be, of course, the 230 pounds or so of me plus engine plus fuel plus accessories and baggage. Since there are no wings to produce lift, all of the forces will be supplied by the engine. This number will be the vector sum of 230 pounds of lift and 58 pounds of thrust, or  $\sqrt {{230}^{2}+{58}^{2}}=237$ pounds. And thrust (force, that is) times speed is equal to power so we're looking at (calculation and unit conversions available on request) about 38 horsepower.

It's unimaginable to me that someone would actually climb to 5,000 feet in this rig, at least to commute. But let's say I climb to 1,500 feet to clear buildings, etc. I'd use about 470,000 joules to do so (calculations available upon request). I'll assume that the MYT engine has an efficiency of 30% at full power (generous) so I'd need 1,410,000 joules of thermal energy from burning fuel. This is about 0.01 gallons so I'll neglect it.

Next, 38 horsepower is 28,300 joules per second or about 102 million joules/hour. Again, assuming we burn fuel and provide thrust at 30% efficiency, this means we'd burn fuel to attain 102 million/0.3 or 340 million joules of heat energy. It appears that the engine runs on kerosene (diesel fuel) whose heat of combustion is about 142 million joules per gallon. So we're burning 340/142 or 2.4 gallons per hour. Note that this is actually slightly LESS than claimed by Morgado, a tendency toward conservative claims that's rarely seen in the world of promoting breakthrough inventions. I'll use my number. Thus, the 1.5 gallons will last about 37.5 minutes and provide an empty tank range of 37.5 miles (we're traveling at a mile per minute).

I don't know about Mr. Allan or Mr. Morgado, but I don't want to burn my last ounce of fuel and then parachute to the ground, so I'd probably limit my range to 30 miles or so. But, all that said, it's still not out of the realm of practicality. And there's sufficient capacity to add another several gallons of fuel.

Many other claims of uses for the engine design are made, up to and including "flying cargo ships," I'd encourage the reader to take a look. I don't know if the engine actually works, what its durability and reliability are, what problems might arise in such a configuration, etc. but I don't think that Sterling Allan is wholly out in left field on this one. I'm going to stay tuned.

Update: To GRLCowan and others, yes, I know I owe an update on sequestration via carbonate minerals. It's being worked on (honest) but I'm having to learn and relearn a LOT.

Update 2: While I can't find photos or sketches showing the configuration of the Angel Flight Pack, and Allan talks on occasion in discussing the MYT engine of "turbines," I speculate that the MYT engine is driving a ducted fan in the Angel Flight Pack consideration. Such a thrust producer may operate at an efficiency of something like 75% to 80%, so the 2.4 gallons per hour I mentioned should be divided by 0.75 or 0.8 to yield 3.2 gallons per hour to 3.0 gallons per hour, right at the number claimed by Morgado. Thus, the empty tank range is likely 30 miles or so (without installing additional fuel capacity) and I'd hold it to 25 miles.

The breakthrough characteristic is the ability to burn a lot of fuel in a short time in a small overall volume and consequent low weight. This characteristic would increase in value as the engine increases in size. I'm tentatively (assuming the considerations I mentioned above, such as durability, reliability, etc. are favorable) a fan of the engine.

Update 3: Here is an extensive article and lots of informed commentary on the MYT engine and earlier examples of the "swing piston" design. It's pretty clear that, at best, there are many problems to be overcome - in particular, heat dissipation and sealing. Whether the MYT engine can be successfully produced and brought to market is questionable at best. That said, IF a power plant with the characteristics claimed by Morgado can be produced, I'd contend that the "Angel Flight Pack" is possible.

## Thursday, October 17, 2013

### Blog host ethics

Certainly there are no laws on the ethics of hosting/publishing a blog and there are all manner of blogs out there. Some thrive on flame wars, insult hurling, etc. and do no moderation. Others are moderated strictly and say so up front. Still others, though, represent that they welcome open dialogue but moderate comments that disagree with the host's point of view. In my opinion, this is or should be in violation of what I'd consider to be a "blog publisher code of ethics."

The case in point involved a blog to which I linked from mine up until yesterday. It's published by Mark Chu-Carroll ("MarkCC") who publishes "Good Math Bad Math." This blog covers quite a few things that are of interest to me, among which are computer science, math and physics crackpottery, (lately) probability, and others. MarkCC also discusses recipes, music, and other eclectica.

But MarkCC will also delve into social issues and clearly comes from an extremely liberal viewpoint. That's all well and good and I certainly respect his right to hold, promote, and publish his point of view, though I frequently disagree.

Yesterday, MarkCC published a post entitled "It's easy not to harass women." And while I agreed with some of what he wrote and with some of the comments, I hold a contrary point of view on a few of the things. In particular, it's my opinion that the legal, legislative and administrative machinery make it all too easy for opportunists to hold employers, institutions, etc. hostage with the threat of lawsuits over things that may rightly be considered offensive or not even that. Careers, families, etc. are ruined in response to perceived slights using a regulatory schema that rightly seeks to protect (most commonly but certainly not exclusively) women from reprehensible conduct such as the "casting couch," offer of career advancement or employment in return for sexual favors, and other such clearly actionable conduct.

This happens despite the fact that no harassment or sexual innuendo was intended. I do not speak hypothetically. And, frankly, unwelcome sexual innuendo should be handled without lawsuits and without destroying people. And, let there be no doubt, this is neither to condone such behavior nor to suggest that there are no behaviors that merit the full legal arsenal.

On MarkCC's site, I left several comments. None were vulgar, extreme, or confrontational. None were of an ad hominem nature. But, after the first couple of comments and literally in the middle of discussion threads, my comments disappeared without notice or explanation. In fact, a reply to one my purged comments was left so that the subsequent comment was replying to a comment that was no longer there.

Now, can MarkCC do this? Obviously, since he did, he can. Should he be able to? Absolutely and unequivocally, yes. Do I think it's ethical or right? I do not. My respect for Mark has declined precipitously.

Am I writing this in "revenge?" Heavens no, I doubt that MarkCC will ever know that I wrote it and I doubt that his commenters and readers will ever see it, his readership is much larger than mine. But I did want to "get it on the table" and assure my readership that, if it's not spam and it doesn't make a threat, all comments at my site will stay. Even if they insult me personally (which some have).