Wind Turbines: If It Looks Good…

Mick Sagrillo writes in Solar Today about the plethora of “revolutionary” wind turbines being hyped out there, which look wa-a-y cooler than conventional wind generators. The enthusiastic developers imagine that these designs are not only good looking, but also will generate all the energy you need.

Sagrillo, handicapped by actually knowing what he is talking about, is distressed by the ignorance of these pitches [2]. As he says,

“Don’t you think that before one thinks outside the box, one ought to at least know what’s inside the box? And why is it in there?” (p. 55)

Grump, grump, grump.

As he points out, wind energy is pretty well understood, and is based on the unforgiving physics of fluid dynamics. Like gravity, these rules are not just a good idea, they are the law.

The big variables are in the site, how high off the ground, and the size of the turbine. Most alternative turbine designs (assuming they work at all) are roughly equivalent, and the difference are tiny compared to the effects of, say how high the turbine is, and whether trees are nearby. (And, by the way, don’t forget that there is a bit of work to connect it to anything useful.)

If you are really interested in getting usable wind power, then you need to use well designed turbines (Sagrillo points to this reference from Interstate Turbine Advisory Council (ITAC)).

I think Mr. Sagrillo is a bit too harsh when he says, “If you must buy a “spinny thing”, buy a whirly gig at a craft fair.” (p. 55). Ouch!  Harsh!  Not everyone is interested in wind power solely for the power.

If we want something that looks like part of a Ray Gun Emplacement left behind by Emperor Ming of Mongo, why not? Why not a cool looking “spinny thing” that generates a little electricity? If it gives you pleasure, go ahead.

But please don’t be fooled into paying absurd amounts of money on the hope you will recoup it from the energy produced.

Several cool looking small wind turbines. Not necessarily recommended.
Several cool looking small wind turbines. Not necessarily recommended.

  1. Interstate Turbine Advisory Council (ITAC). ITAC Unified List of Wind Turbines. 2016,
  2. Mick Sagrillo,  (2016) “Wind Doesn’t Work” (or Does It?). Solar Today, 54-55


Ethereum Follies, October Edition

The Ethereum project continues to give a public tutorial in how not to do secure network software.

Ethereum is built on concepts pioneered by Bitcoin, adding on an additional layer to implement executable contracts (which are usually mis-termed “smart contracts”). This is pretty much uncharted territory, though fundamental computer science teaches us that a Turing complete programming language is going to be vulnerable to all kinds of mischief.

Ethereum deals with the main forms of mischief by throttling the Turing machine (so it is technically a modified TM), running in a restricted virtual machine and using a tax (“called “steam”) on each operation. The idea of the charging  is that trouble makers will be deterred by having a toll booth. “Please insert 25 cents to continue running.”

As a philosophical aside, I note that this approach moves the question of whether Ethereum is vulnerable to the question, “is this (complicated) virtual machine with its coin slot vulnerable?”

Rushing to market, Ethereum went into production with more confidence than hard testing. Then a group decided to go one bridge farther, to create a full blown Decentralized Autonomous Organization on top of Ethereum. Lot’s of people have been talking about DAO’s, imagining that they are solutions to all that ails us. Much of the enthusiasm apparently stems from the “logical” syllogism:

  • Organizations (states, companies, banks) cannot be trusted
  • Organizations are operated by people
  • DAOs operate robotically, i.e., without people
  • Therefore, DAOs can be trusted


Another philosophical aside: DAOs operated by executing code. Code is created by people. To be fair, proponents of DAOs are mostly concerned that the powers that be simply don’t follow the rules, whatever they are. Robots at least will blindly follow the rules, whatever they are.

Anyway, the rickety tower that was the DAO came crashing down, after a classic, and very brief, tulip mania. The robot assisted tulip mania shattered not only the DAO but Ethereum itself.

Responding to the DAO disaster, Ethereum developers hacked the code to rewrite history. This did not go as well as intended.

Another philosophical aside: the entire point of cryptocurrency in general and Ethereum in particular is that “insiders” should not be able to rewrite history. The forked Ethereum “solved” the DAO problem at the expense of the integrity of the fundamental concept of cryptocurrency.

Since that time, Ethereum has suffered a stream of attacks, likely motivated by the high handed “fix”, as well as the extremely large number of ways you can mess with the system.

Last month, Ethereum did yet another rewrite, this time to fiddle with the pricing. Essentially, the postage was low enough that it failed to deter “spam”. In the crazy world of cryptocurrency, changing the postage rates requires a massive change to the software, and also requires every post office in the world agree to the new rates.

Anyway, this month it is clear that this fix did not solve all the problems. Further hacks are planned.

At this point, is there any reason to think Ethereum is better for all these changes?

Who knows?

It is pretty clear that Ethereum was never subjected to serious adversarial testing before it was released. Essentially, we are watching the grinding, grueling process that should have happened earlier, using the “live” system that people are putting real money into. Best case, this is not great engineering.  (Worst case, this is professional malpractice bordering on negligence.)

I  wonder just how solid the new “pricing” model actually is.  It is abundantly clear that the new “fixes” have not been extensively tested.

Fundamentally, the notion that charging postage will deter misuse—if only we get the price schedule just right—seems pretty iffy to me. There are so many untested assumptions in that model that I can’t believe it can be proven correct or even reasonably safe.

So many bad ideas, so little time to blog about them….


Cryptocurrency Thursday

Crawly Robots

At this month’s IROS, Shixin Mao and colleagues showed a cool demo of “crawly” robots. These bio-inspired soft robots walk using soft legs, inspired by star fish!

The abstract indicates that the legs are actuated by shape memory alloys, which are simple, rugged, and energy efficient. Ideal for robots.

The work explored gaits with different numbers of legs, inspired by star fish which may lose and regenerate legs, but continue to walk with many different configurations. This, too, would be a useful trait for a robot, no?


I love the biomimetic design here, and the bots are fascinating. I look forward to hearing more from this project.

  1. Shixin Mao, Erbao Dong, Hu Jin, Min Xu, and K.H. Low, Locomotion and Gait Analysis of Multi-Limb Soft Robots Based on Smart Actuators in IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS 2016) 2016: Daejeon.


Robot Wednesday

Hao Li’s Cool AR “For Meetings”

Hao Li of USC is making a bit of buzz with his Virtual Reality / Augmented Reality developments.

Li is quite interested in the physical and virtual, and has been messing around with Oculus and other technologies.

His latest thing is a cool combination of VR goggles with real time scanning of your eyes and the rest of your face, i.e., your mouth and lips. The idea is to capture the facial expression and project it into the VR scene, so that an avatar can precisely mimic your motions. I.e., when you talk or smile or whatever, the avatar does exactly the same expression. (The video makes this clearer.)

What is this for? One idea is for “face-to-face” meetings in a virtual space. As their press release suggests, “what if you could show up to the next meeting as Gandalf from The Lord of the Rings, the Night King from Game of Thrones or a talking pizza?

This is pretty neat, and a step up from the earlier work from the HITLab (NZ, and Washington), which was doing stuff like this a decade ago and more. One of the more memorable demos from Sensei Mark Billinghurst and Co was an AR Halloween party: the partiers wear AR goggles and each pastes a marker on their forehead. The AR system projects different masks over each of our heads. (It’s kind of like liar’s poker: everyone by me can see my costume!) Here is a video from 2007, much of the work dates from several years earlier (YouTube didn’t really exist before 2006.)

Li’s stuff is fancier, though I’m not sure it is better. Do I want my “mask” to reveal my facial expressions, or do I want it to conceal them? Sometimes, I want the latter, no? As Li’s  own press release says, “even if you’re an orc, your co-workers will still see you rolling your eyes in total boredom during the meeting.” Which is kind of bogus, IMO.

Furthermore, it isn’t obvious to me that “meetings” are a particularly good use for this technology. Aside from the question of whether I want to reveal myself, I don’t see how dinking around with cosplay will make meetings better.

After all, when people complain about meetings, they generally don’t complain that “the meeting room didn’t have dragons and unicorns in it”. Mostly people would like meetings to focus on the topic and get over quickly. Making them “fun” is really the wrong idea from that point of view.

Li’s stuff is undeniably awesome, and is a great thing to play around with. But he needs to come up with a better cover story, because the “better meetings thing” just isn’t going to fly!

  1. Daniel Druhora, Who wants to show up as Gandalf at their next meeting?, in USCNews. 2016.

The Just Things Foundation Wants to Make Responsible IoT

Last year I endorsed and signed on to the IOT Manifesto, which calls for and aims to articulate “Guidelines for responsible design in a connected world”.

This effort has now spawned the Just Things Foundation (which is an exquisite pun in English), which “builds on these principles and aims to transform them into actionable standards for a broader audience to work with.

They also dream of “tools for professionals”, and I am very curious to know what they mean by that.

JustThings will be presenting an exhibition at Dutch Design Week Eindhoven this week, they call, “An Internet of Things We Can Be Proud of”.  As the poster says, “Why does my refridgerator need to know my birthday?

I will be interested to see more about this exihibition.

By coincidence, this week saw an appalling cyber attack which is reported to exploit major design flaws in some of the current generation of IoT devices. Absolutely no one is surprised by this event, nor at the irresponsibility of the companies that sold these awful things that are now crippling our DNS. Thanks, a lot, guys.

This incident is a clear reminder of how much we need better design, much, much better design of IoT devices.

I stand with Just Things, and I urge everyone to support their efforts.

Book Review: “Pax Romana” by Adrian Goldsworthy

Pax Romana by Adrian Goldsworthy

Adrian Goldsworthy’s latest book aims to examine what “Pax Romana” actually was, and how it was achieved. The term refers to the centuries of dominance of the Roman Empire, enforced by overwhelming military power, as well as diplomatic and economic hegemony.

But what does “Pax” (peace) mean? There was certainly armed conflict during those times, including major foreign and civil wars, disorder, piracy and bandits, and a variety military operations. For that matter, the Pax was maintained by hundreds of thousands of troops on active duty from Scotland to Arabia.

On the other hand, many places experienced safety and very little military violence for unprecedented periods of time. Commerce thrived across great distances, and law replaced combat for most local disputes.

Goldsworthy wants to work out a balanced assessment of how the Roman system really worked, with an eye to how “Pax” was experienced by people in many walks of life. To a certain extent, he is revising revisionist histories, actually multiple revisions of history.

Rome has been a fascination of scholars for a long time, and there has certainly been a tendency to project contemporary concerns onto the incomplete information we have about the ancient empire. As a result there have been many interpretations of Roman history which lean heavily on preconceived or anachronistic ideas.

One reason there have been so many different interpretations is that the first hand evidence consists of ancient texts (written by Romans) and archaeology. There are quite an array of texts, but they are fragmentary, often lack context, and mostly represent the view of certain Romans. (One exception is the conflicts between the Romans and Jews, which are documented from several sides.) The archaeology is unevenly distributed, and difficult to interpret unless there is sufficient context, but shows remains from everyday life that did not reach the written record.

Goldsworthy wants to sift through all this evidence to give us an overall picture faithful to the Romans themselves. He does a reasonable job of letting us know what he thinks without totally obscuring the views of earlier scholars.

The overall picture is of an active and aggressive military and diplomatic power, that enforced “peace” in its provinces and out into neighboring states, whether they wanted it or not. But who’s who and who did what is less clear.

For one thing, the Romans were amazingly good at absorbing newcomers into their system, and also were adept at diplomacy to support “friendly” neighbors. It can be very confusing to try to understand what the “sides” are, and who is fighting who.

So, in the end, what were the Romans up to?

Goldsworthy see Romans as always interested in dominance, and of acquiring profits from their military dominance. As he says, they were always open on this point: what mattered was winning, and exploiting the dominated for the benefit of Rome. Goldsworthy argues that once conquered, Rome needed to keep the peace within the provinces and protect them from external attack. This “Pax” stemmed from self-interest, it was not the goal of conquest.

The Roman state wasn’t democratic or humane or interested in the well being of anyone except the ruling elites; and the “peace” was never perfect, large areas did experience comparative peace and prosperity for centuries. And this Goldsworthy says, is worth admiration.

This book is a popular history, with sources but not obsessive citations. His prose is clear and readable, though I had plenty of trouble with the geography and dates—he tends to assume I know where Roman provinces and cities are, and the time period of the leaders, which I don’t.

As a broad, general history, he breezes through stuff, jumps around, and summarizes sources with little explanation. It’s hard to follow, and even harder to judge his arguments. In some cases, I know enough about the sources to trust his coverage, but other places (e.g., the Jewish and Christian sources, and some of his economic analyses), his interpretation seems to stretch awfully far based on highly questionable sources.  That makes me worry about his other generalizations.

But overall, his point is not to draw conclusions (or grind axes) about current concerns. Rome was Rome, and he wants us to understand it in its own terms. I certainly agree with that.

  1. Adrian Goldsworthy, Pax Romana: War Peace and Conquest in the Roman World, New Haven, Yale, 2016.


Sunday Book Reviews

Quantum Dot Coating for Solar Power Windows

In recent years there has been considerable progress in the development of photovoltaic (PV) capture of solar energy from window glass. Eschewing fields of solar collectors, this technology seeks to make every window and glass wall capture light and generate electricity. If this can be done efficiently, then every window in every building can provide electric power for its inhabitants. Cool!

As Andrew Silver reports, the basic idea is to apply a coating that is excited by light, and feed that voltage to the edge of the windowpane, where it is accumulated and can be used. This has been tried with dyes (i.e., tinted windows in which the tint generates electricity), but attention has turned to quantum dots.

A team from Los Alamos National Lab have published a promising approach which extends earlier work to use an inexpensive process to deposit a film of quantum dots onto ordinary glass. These devices are tuned to capture quite a bit of the spectrum of sunlight, which generates a trickle of electricity. (Actually, the process is complicated: high energy photons are captured, generating electrons, which hop out and generate low energy photons, which propagate to the edges of the glass.)

This technology is still in the lab, but it is very interesting because it is simple, cheap, and rugged, and therefore something that could realistically used in mass production.

This is also notable because it demonstrates that nanoscale devices (quantum dots) can be used over a wide area (a windowpane). Cool!

  1. Hongbo Li, Kaifeng Wu, Jaehoon Lim, Hyung-Jun Song, and Victor I. Klimov, Doctor-blade deposition of quantum dots onto standard window glass for low-loss large-area luminescent solar concentrators. Nature Energy, 1:16157, 10/10/online 2016.
  2. Andrew Silver, Quantum-Dot Coating Could Pull Solar Energy From Your Windows, in Energywise. 2016.

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