Low hanging fruit revisited

Photo credit: Lincolnloop.com

About three years ago, I posted an article on the "low hanging fruit" in fuel savings. In that article, I demonstrated that for a given increase in m.p.g., the lower the starting m.p.g. (before the increase) the more fuel will be saved by that increase. Thus, a driver who drives 12,000 miles per year and increases from 15 m.p.g. to 18 m.p.g., either by purchasing a new vehicle or changing driving habits, will save about 133 gallons of gasoline per year. Another 12,000 miles per year driver who increases from 25 m.p.g. to 28 m.p.g. will save only about 51 gallons per year. The best way to understand this is to think of gallons per mile or, more transparently, gallons per 100 miles, the inverse of m.p.g. This number is 100*1/(m.p.g.) Thus, the first driver uses 6.67 gallons per 100 miles before the change and 5.56 gallons per 100 miles after. This driver saves 1.11 gallons every 100 miles. The second uses 4 gallons per 100 miles before and 3.57 after. This driver saves 0.43 gallons every 100 miles.

I was reminded of that post by this article in Energy Trends Insider. The article discusses a construct from the Department of Energy (DOE) at a new website that discusses the so-called "eGallon." This number purports to give the quantity (or cost) of the electricity that it would take to move a "typical" electric vehicle (EV) as far as a gallon of gasoline takes an "average" conventional car. This is where the "low hanging fruit" concept comes in. Replacing a 20 m.p.g. vehicle with an EV saves MUCH more than replacing a 30 m.p.g. vehicle. The 30 m.p.g. vehicle goes half again as far on a gallon and thus the eGallon costs more for that driver.

I applaud the DOE for attempting to clarify the possible savings in fuel expenditure vs. electricity expenditure but, in some cases, it may be very misleading. The calculation is further complicated by the wide variance in how electricity is priced in various localities.

As to the "low hanging fruit," the plot below shows, for a driver who drives 12,000 miles per year, how many gallons of fuel are saved per year by moving from one m.p.g. driving regime to a higher one. It plots initial m.p.g. from 10 to 40 and final m.p.g. from whatever was the initial m.p.g. to 120 m.p.g.  The "front" axis is initial m.p.g., the axis that extends back and right is final m.p.g., and the vertical axis is gallons saved. As can be seen in the rightmost portion, the savings from a high starting point are not nearly as large. It's also easy to see, especially at the left end, that the big gains are in the initial improvements - the slope is dramatically steeper than at the higher final numbers.

India burning coal at fastest pace in 31 years, will eclipse China as world’s coal power

India burning coal at fastest pace in 31 years, will eclipse China as world’s coal power:

'via Blog this'

 Yes, well, it's hard to imagine that a country or society that lets these things happen is going to care much about CO2 emissions from a coal fired power plant (not that we in the U.S. don't have our own slums and our own group of people who don't care about CO2 emissions from coal fired power plants).

Misallocation

A couple of things will come as no surprise to my regular readers. The first is that I consider myself to be a true conservative and that the foolishness, hypocrisy, obstructionism, and fact-free opining that passes for conservative commentary today is a source of deep embarrassment to me. The second is that I consider the ability to ensure a reliable and sustainable supply of primary energy to be one of, if not the, greatest and most important challenges we face not only in our nation but in the world (the other possibilities include "peak everything" and self-poisoning of our species, the latter including pollution of all types, CO2 emissions, etc.).

Thus, it is deeply disappointing, though not particularly surprising, that the full House Appropriations Committee approved along party lines, a bill with deep cuts to renewable energy projects and, particularly, to arpa-e, an organization whose annual "Energy Innovation Summit" I've attended the last three years. The $30.4B bill is $2.9B below the 2013 level and $700M below the sequestration level. arpa-e, in particular, received a cut from $252M to $50M, a reduction of 80.8%. This is tantamount to the committee saying "we don't want arpa-e." President Obama (of whom I'm certainly no fan) requested $379M. You can read the committee's press release here.

arpa-e is engaged in funding of high risk, high reward projects in the energy field and funds technologies from fuels and generation to storage to distribution to control, as well as carbon capture, efficiency in buildings, transportation technologies, and many others. Can anyone deny that these technologies constitute the way forward in a coming (if not here already) time of energy limits?

Energy Subcommittee Chairman Rodney Frelinguysen (R-N.J.) was quoted as saying "It is our job to make do with what we have, not with what we hope to have." I wonder where the money could possibly be found?

Down the rabbit hole...

Image Credit: Dr. Dave Goldberg at io9.com

There sure are a lot of people out there that are much smarter than Einstein, Dirac, Boltzmann, Maxwell, etc.

In my post on the MIST Engine, I stumbled upon a treasure trove of unrecognized brilliance.

Amuse yourself with these geniuses at your leisure. If only mainstream science weren't so closed-minded, physicists and cosmologists could be open to such brilliance.

Update: Woah! This one is simply too good to leave out!

"Free" energy

Image Credit: Sweet Samoa

In my feeds from the soon to be late, lamented Google Reader (the company whose motto should change to "Evil R Us") I've included the aggregator "Alternative Energy News." Many of the articles are interesting and discuss important ideas and developments. Others... not so much. For example, articles from "Pure Energy Systems Network" (PESN)" are aggregated. This is a site that delves into the world of such exotica as gaining useful energy from  zero point energy, magnet motors, motors that are alleged to run on the energy in cavitation, energy from "low energy nuclear reactions (LENR - the new name for what used to be called 'cold fusion')," and others. The sense of the site is, unsurprisingly, that any or all of these could change the world but for the oppression of the powers that be (our government and corporate overseers).

The subject of this post is the "Molecular Impact Steam Technology (MIST)" engine. This technology claims to utilize hypersonic water jets to "explode hydrogen bonds" in water, thereby releasing enormous energy, thus producing dry steam without heat input. MIST claims a "10:1 overunity factor," meaning that the energy available in the steam is 10 times greater than the energy used by the pump utilized for the water jets.

The claim is that one pound of water, using 127 btu of input energy results in dry steam with an energy content of 1,100 btu. First, let's convert to SI units using Cloudy. Rephrasing, 134*10^5 joules converts 0.454 kilograms (or 25.2 moles) of water into steam with an energy content of 1.16*10^6 joules.

Now, typically energy is released upon the FORMATION of bonds, not on the breaking of bonds (nuclear fission of atoms larger than iron is, of course, an exception). Therefore, the "exploding of hydrogen bonds" does not pass the initial "sniff test." Enthalpy of formation of hydrogen bonds in water is subject to significant variation, but a reasonable number is about -23.3 kJ/mol. This means that the formation of hydrogen bonds RELEASES about 23.3 kJ (kilojoules) for each mole of water. These 23.3 kJ must be SUPPLIED to each mole to break these bonds. In other words, energy must be supplied to break the bonds, breaking them does not release energy.

On their web site, there are many pages with calculations and data and a couple of papers on tangentially related topics. I'll dissect one such page.

The claim is that the increase in specific kinetic energy (J/g or J/kg) in moving from a jet velocity of 810 m/s (where there was no dissociation from liquid water to steam when the jet impacted the chamber wall) to 3000 m/s (when steam was created) is from 320,000 J/kg to 4,500,000 J/kg. This is correct. But they claim this proportionality to v^2 as a kind of "mechanical advantage." Of course, the energy to accelerate the water must be supplied to the pump.

They then meander into a paragraph that mentions a 10 h.p. pump providing the pressure to process 120 pounds of water per hour. They state that 10 h.p. is 7.46 kW. So far, so good. They then divide by 60 and state that this is 124.3 watts per minute. Say what? Watts is already a "per unit time" unit. That is, the watt is a rate, not a quantity. Watts per minute is an acceleration of power, surely not what they mean. Heaven knows what they DO mean.

They then say that they pump 2 pounds of water per minute at 30,000 p.s.i. and 3,000 m/s. They next state that this is "1139 watts using only 124.3 watts of energy." Oh, brother! The watt is not an energy unit, it's a rate of supplying energy or doing work. The 124.3 came from  dividing the pump power of 7.46 kW by 60 for reasons unknown. So they believe that they're getting 1139 watts of output for 124.3 watts of input and that "the rest of the energy comes from the energy contained within the bonding of the molecules of water." Of course, breaking these bonds ABSORBS energy (specifically, around 20 kJ/mol or 1,120 kJ/kg).

It's hard to know whether they're aware that they're selling snake oil or just misguided. Perhaps they create steam more efficiently than a flame fire-tube or water-tube boiler (I'm no expert on the efficiency of boilers) but they certainly aren't achieving overunity by the freeing of hydrogen bond energy in water.

Wasted energy

Nope, I'm not talking about the 75% of the energy in the gasoline in your car going out the exhaust pipe as waste heat, or the cooled/heated air escaping your house because it's not as "tight" as it could be. I'm not talking about anything to do with the inefficiency of the use of primary energy. I'm (against my usual nature) using a more colloquial meaning of "energy" here. I'm talking about foolish expenditures of "mental energy" on schemes that either will produce no useful energetic results or such a trivial amount of energy that it's a waste of time to bother.

I've previously written of the foolishness of humans as generators via walking and revolving doors, the silliness of one of the Discovery Channel's "Project Earth" programs (they were all fairly silly but I focused on a specific one). I've got two more examples.

The first is something akin to the "human powered generator," that is, it would probably work from a technical point of view but be useless in any practical way. I was pointed to it by a post in Tom Sanwson's Swans on Tea blog entitled "This Claim Won't Fly." The post referred to an article on CNN's site about Airbus working with UNESCO to challenge engineering students in a "Fly Your Ideas" competition.

Of the ideas described in the article, one sounds far out (shape shifting engines to reduce noise footprint), one marginally practical (powering jets with a supercooled mixture of biomethane and LNG), and one ... let's just say silly. That last one is to use seats upholstered in a thermoelectric fabric to use passengers' body heat to generate electricity. University Putra Malaysia team leader Tan Kai Jun envisions generating "100 nanowatts of voltage." Like Tom Swanson, I'll ignore the fact that watts is not a unit of voltage, but rather a unit of power.

"It's a small amount, but imagine this collected from 550 seats throughout 10 hours of flight. A plane has a lifespan of a few hundred flights -- over time that's a big reduction," Mr. Jun Tan says."

Tom ran some numbers, but I'll do the same. The "age" of an airliner is measured in pressurization cycles, and a "typical" airliner may have 51,000 flight hours and 75,000 pressurization cycles in its useful life. Let's consider an airliner with 400 seats (say, a B777) and 51,000 hours. We'll assume the plane flies with an average load capacity of 95%. So we have 400*51000*.95 = 19,380,000 seat hours. Using the the Google Chrome extension "Cloudy Calculator" and multiplying hours times 100 nanowatts (the calculator does all conversions) we find that we've generated 1.9 watt hours over the life of the aircraft. I pay about $0.12 (12 cents) per kilowatt hour at my house, so this almost two watt hours is worth a smidgen (one of my favorite units - slightly smaller than a skosh) over a fiftieth of a penny.

Looked at another way, Jet A fuel (used in airliners) has an energy density of 35.3 megajoules per liter. 1.9 watt hours is about 7,000 joules, or 0.007 megajoules. So, over the lifetime of the airplane, the passengers would generate electrical energy equal to the chemical potential energy in 0.2 milliliters of jet fuel. Of course, a heat engine such as a turbofan might operate at, say, 45% efficiency so we'd actually need to burn a bit under half a milliliter to generate those 1.9 watt hours. I suspect that this development will not revolutionize flying.

The next post will cover a different type of silliness - one that's either a fraud or pie in the sky.

Embarrassed to be conservative one more time (but likely not the last)

As I've stated repeatedly, I'm conservative by nature. I'd like to conserve resources (financial, natural) and our civil liberties. This is what conservatism means to me and what it used to mean to others who so self-label. Now, though, it seems to have come to mean "conserving my opinion on the way things are regardless of factual evidence that I'm wrong." An entire media universe has sprung up around this false conservatism, nowhere more clearly demonstrated than in Fox News' coverage of science.

Below is an embedded clip from "Media Matters" with some of sillier utterances of false conservative talking heads. Please don't construe my embedding of this video as an endorsement of the politics of Media Matters, I'm in deep disagreement with their viewpoint on many matters as well. But watching Bill Nye the Science Guy when he's asked if volcanoes on the moon are related to global warming on Earth is priceless. He clearly is struggling to retain his composure when asked a question that any sixth grader should understand is ludicrous. And birds will redo their chromosomes in a generation or two???

I'm going to have to come up with a new name for my point of view - identification with such as these is repugnant.

Privacy

Certainly, this post will stray from my topic space as I've done in the past. I feel compelled to opine on the NSA leaks saga (purposely not calling it the Edward Snowden saga for reasons that will be apparent).

In my life I've been a tin foil hat arch right wing reactionary, a socialist, a strident atheist, a Christian (as I believe today), a doctrinaire libertarian, and many others. But one thing in my belief system and philosophy that has never wavered is my staunch belief in a right to privacy. The Fourth Amendment ostensibly assures us of our right to be "secure in our persons, houses, papers, and effects, against unreasonable searches and seizures...."


This right has been continuously eroded by Congress, by the Courts, and by the Executive branch. In my opinion, far and away the most egregious violation is the odious "USA Patriot Act of 2001." In causing the Congress to pass, the President to sign, and the people to accept this blatant violation of the founding principles of our Country, Al Queda and Bin Laden in fact have won. The nation we were no longer exists.

Now, of course, the ability to infiltrate into every private area of all of our lives should the mood strike has been the heartfelt desire of anyone involved in law enforcement, no matter how tangentially, from time immemorial. But it wasn't to have happened here.

Now, along comes Edward Snowden. I'm completely disinterested in who he is, what his motivation was, where he went to school (or didn't), or anything else about him personally. My forlorn hope is that his revelations will cause a backlash against the encroaching "security at any cost" rationale behind the actual "we need the power because we want it" motivation of our security nation overseers and the actions they've undertaken to accomplish this goal.

Sadly, the propaganda machine, from right to left, has succeeded in making the debate (such as it is) about Snowden. Is he a traitor? A whistleblower? A Chinese spy? A frustrated loser? A narcissist with a martyr complex?

I don't care. The fact is that those who have promulgated and supported the activities revealed by Snowden are the real traitors here, and that will be lost in the debate about Snowden.

Rates vs. quantities - more unit confusion

It's widely accepted (though not universally) in the renewable energy/clean tech/green community that one of THE major problems in the widespread adoption of such renewable sources of electricity as solar and wind is their intermittent character. It's further believed that the ability to store the energy from these sources will enable their intermittency to be smoothed out, thus making them a reliable source of energy and enabling them to become much more easily integrated into the grid, possibly even a source of baseload power.

I read today that my state, California, has, through our Public Utilities Commission, set a goal of "1.3 gigawatts of energy storage by 2020." My state is certainly at the leading edge of sustainability with AB32, the Global Warming Solutions Act of 2006, the Cap and Trade Program, and many others. But I worry about people who make laws write regulations and yet aren't able to distinguish between rates and quantities.

Here's a link to the Assigned Commissioner's Ruling on this. Throughout the document, Carla Peterman discusses storage in megawatts. But a "watt" is a rate of energy utilization, or rate of performing work. A megawatt is a million joules per second. Certainly, the rate at which a storage system can deliver energy is important, but the key is the quantity that can be stored. This would be measured in watt hours, kilowatt hours, megawatt hours, gigawatt hours, terawatt hours, etc. Or, equivalently, in joules, megajoules, etc. Saying "we need 1.3 gigawatts of storage" is analogous to saying San Francisco is 80 miles per hour away from Los Angeles.

A typical gasoline pump will pump, conservatively, around five gallons per minute. Each gallon of gasoline has a chemical potential energy through oxidation of about 132 megajoules. Thus, when you fill your tank, you're delivering energy at the rate of 132*10^6 joules/gallon * 5 gallons per minute/60 seconds per minute or 11 megawatts. About 120 people filling their tanks are delivering energy at about the 1.3 gigawatts mentioned by the PUC. But this doesn't tell you a thing about how many miles these 120 drivers can travel. To know that, you need to know the capacity of the 120 tanks in gallons (along with the rate of fuel consumption of the vehicles).

To provide a bit of orientation as to the rates being discussed, in 2011, California generated or imported a total of about 292,454 gigawatt hours of electricity. This is a rate of about 33.36 gigawatts so the storage being discussed could deliver a bit under 4% of the average California rate of electricity usage.  Of course, the planned storage is divided between different utilities and geographical locations and would be deployed locally. But key to the discussion is FOR HOW LONG? A second? A minute? An hour? A day? Nothing in the document tells us.

Addendum, June 15, 2013: It's bad blog form to edit a posted blog without saying so. In reviewing the above, I realize that, while it's quite true that capacity is a fundamental metric of the viability and practicality of storage, rate is also important. I alluded to that above but I want to make it clear that I realize that vast capacity is not relevant if the rate at which it can be delivered isn't matched to the demand present in the area served.

This merits a bit of analysis of what sort of capacity might "match" a delivery rate of 1.3 gigawatts. For a starting point, let's take a look at the 4% calculated above. And I'll arbitrarily assume that we'd like to be able to "even out" the output from intermittent sources over a 24 hour period with a reserve capacity (no wind, cloud covered sky, whatever) for three days. In three days, on average, California might use (3/365)*29,2454 or about 2,400 gigawatt hours of electrical energy. 4% of this is 96 gigawatt hours.

Arguably, the storage method with the best combination of capacity, dispatchability, delivery rate, and efficiency is pumped hydro storage. If we assume a round trip efficiency of 75%, we'll need to store 128 gigawatt hours of energy. Hoover Dam delivered, at its 1984 peak, 10.348 terawatt hours so, in an average three day period in 1984, it delivered 10348*(3/365) = 85 gigawatt hours. So we're talking about something like one and a half Lake Mead/Hoover Dam storage schemes.

By the way, this goes to show just what an amazing resource gasoline is. 3032 gasoline pumps can deliver the energy equivalent to the entirety of California's average electrical consumption.

Update: The Blenheim-Gilboa Power Station in New York can deliver electricity at the rate of 1.6 gigawatts and, per a comment in a post on pumped hyrdo storage at one of my favorite sites, Do the Math, can deliver this for 16 hours for a total of 25.6 gigawatt hours. Another site says 1,000 megawatts for eight hours, or 8 gigawatt hours. In any case, storage of the magnitude specified is certainly achievable.

Also, as seen here, it's clear that pumped hydro plants are typically rated in rate in watts rather than capacity and, in fact, it's difficult to find the energy capacity in megawatt hours or gigawatt hours. In a comment in the article linked above, Ben K. say that this is because generating plants are rated in this way. But I don't see that this is a valid reason. A generating plant generates continuously as long as coal, natural gas, uranium, etc. is delivered - the amount of source material is not the issue. In a storage facility, the amount of source material (compressed air, battery chemical potential energy, water, flywheel rotational energy, capacitor electrical charge energy, whatever) is THE issue. After all, we look at battery storage capacity in terms of amp-hours which, at a fixed voltage, is a measure of quantity of energy.