How Cheap Can Solar Get?

Monday, August 24th, 2015

How cheap can solar get, without subsidies, as a function of scale, if current trends hold?

Solar Cost Projections

Why Did Europe Conquer the World?

Sunday, August 16th, 2015

Why Did Europe Conquer the World? Philip T Hoffman’s new book presents a strong case that it was gunpowder technology:

Its starting point is the assertion that Europe really did conquer the world, or at least 84 per cent of it, between 1492 and 1914 — but that you probably would not have bet on that outcome had you landed on Earth in the year 900, when our continent was deeply backward in comparison with the cultural and commercial sophistication of the Muslim Middle East, southern China and Japan.

So why did those early leaders of civilisation stay at home and regress, while our ancestors sailed the seas and built empires?

It was not a matter of economic supremacy through industrialisation, which arrived only in the last of the five centuries or so that Hoffman’s study covers.

Rather, he argues, it was down to both military and economic advantage gained through “gunpowder technology” — the continuing development of firearms, artillery, ships armed with guns and fortifications that could resist bombardment — which itself derived from the fact that warfare was “the sole purpose of early modern states in western Europe”.

The core of Hoffman’s analysis is the idea that European powers were engaged in a centuries-long “tournament” — a competition that drove contestants to exert enormous effort in the hope of winning a prize. In pursuit of “financial gain, territorial expansion, defence of the faith, or the glory of victory”, Europe’s rulers fought each other for two thirds of the time between 1550 and 1700; well over 80 per cent of the annual government budgets of England and Prussia between 1688 and 1790 were spent on waging war. Small amounts of tax revenue and state borrowing were spent on other items of statehood, but by far the bulk was spent on armies and navies.

And this investment in ceaseless fighting brought constant improvements in gunpowder technology, both in productivity — measured by shots per minute per infantryman, as well as killing power — and in costs of deployment: the price of a musket in London in 1620 was as little as 10 days’ worth of an unskilled labourer’s pay. When peace and industrialisation came to Europe in the 19th century, after Waterloo, competitive empire-building became the new tournament, while advances in materiel, including railways and steam-powered ships, made possible the annexation of large areas of the globe by relatively small British and European forces.

Bizarre High-Tech Kidnapping

Tuesday, August 11th, 2015

Bruce Schneier shares some details from a bizarre high-tech kidnapping. Were it an episode of CSI: Cyber, he says, you would never believe it:

FBI court filings unsealed last week showed how Denise Huskins’ kidnappers used anonymous remailers, image sharing sites, Tor, and other people’s Wi-Fi to communicate with the police and the media, scrupulously scrubbing meta data from photos before sending. They tried to use computer spyware and a DropCam to monitor the aftermath of the abduction and had a Parrot radio-controlled drone standing by to pick up the ransom by remote control.


The FBI reached out to Tracfone, which was able to tell the agents that the phone was purchased from a Target store in Pleasant Hill on March 2 at 5:39 pm. Target provided the bureau with a surveillance-cam photo of the buyer: a white male with dark hair and medium build. AT&T turned over records showing the phone had been used within 650 feet of a cell site in South Lake Tahoe.

Transparent Luminescent Solar Concentrators

Sunday, August 9th, 2015

Transparent solar panels face an obvious challenge, but transparent luminescent solar concentrators provide a possible solution:

The solar harvesting system uses small organic molecules developed by Lunt and his team to absorb specific nonvisible wavelengths of sunlight.

“We can tune these materials to pick up just the ultraviolet and the near infrared wavelengths that then ‘glow’ at another wavelength in the infrared,” he said.

The “glowing” infrared light is guided to the edge of the plastic where it is converted to electricity by thin strips of photovoltaic solar cells.

Transparent Luminescent Solar Concentrator

“It opens a lot of area to deploy solar energy in a non-intrusive way,” Lunt said. “It can be used on tall buildings with lots of windows or any kind of mobile device that demands high aesthetic quality like a phone or e-reader. Ultimately we want to make solar harvesting surfaces that you do not even know are there.”

Lunt said more work is needed in order to improve its energy-producing efficiency. Currently it is able to produce a solar conversion efficiency close to 1 percent, but noted they aim to reach efficiencies beyond 5 percent when fully optimized. The best colored LSC has an efficiency of around 7 percent.

Ekso Works

Saturday, August 8th, 2015

Rafe Needleman tried out Ekso Bionics’s new unpowered industrial exoskeleton:

The Ekso Works is a framework you strap yourself into that mechanically transmits the load of equipment attached to mounts at the hip, directly to the ground. You can walk, you can bend, and the gear is supported by the Ekso frame. The Ekso Works provides skeletal strength. You provide the balance and motivation.

To set up for my demo, Harding first handed me a 15-pound industrial angle grinder. It’s heavy, awkward, and a pretty uncomfortable piece of gear to control when it’s at arm’s length or overhead. Using one repetitively can cause stress injuries. Or, if you’re a lightweight like me, you’re likely to drop it on your toes after trying to control it for more than a few minutes.

But when the grinder was attached to a Steadicam-like articulated Equipois mount on the Ekso’s hip attachment point, it became weightless. It still had inertia, of course, but it didn’t weigh a thing, and I could wrench it around like it was a six-ounce pair of pliers. I could hold it over my head easily, and control it with precision. If I wanted to use it at arm’s length, I could do that, too; Counterweights attached to the Ekso’s plate on my back kept my center of gravity over my legs.

And I could walk. It was awkward because it was a new physical experience, but it wasn’t difficult.

One key to all the current Ekso products: The knees. They lock when you’re standing up, just like our real knees. That means that when you’re just standing there, no power input is required. The task of balancing, which does take some energy, is up to the person wearing the device. But as I discovered, even when wearing an elaborate cage of struts and joints, with a spring arm and industrial device strapped to your hip and pounds of steel counterweights on your back, you still know how to balance and walk.

It’s just asking for an M56 Smart Gun.

Escape Dynamics

Sunday, July 26th, 2015

A typical chemical rocket is 90 percent fuel, with the remaining 10 percent split between payload and structure, so an externally powered launch vehicle — one powered by on-the-ground microwave transmitters — has certain advantages:

EDI’s external propulsion launch system will operate at a specific impulse above 750 s and this breakthrough increase in efficiency reduces the fraction of mass dedicated to propellant to less than 72%. The increase of 3x in the mass fraction dedicated to structure and payload for the first time opens doors for reusability and single-stage-to-orbit flight. Our first generation vehicle is optimized for 100-200 kg payloads and is designed to operate like an airplane: the vehicle flies into orbit, delivers the payload, re-enters the atmosphere after completing one or more orbits around Earth and lands back at the spaceport.

EDI External Propulsion

Key benefits of external propulsion:

  • Space launch vehicles become fully and rapidly reusable.
  • Cost per launch can eventually be reduced to $150 per kg.
  • The need for combustion is eliminated, leading to safer and simpler launch vehicles.
  • Useful payload fraction goes up from 1.5-3% to 8-12% and the structural mass is increased by 1.5-2x.
  • Small satellites can be launched as primary payloads allowing higher degree of flexibility for customers.
  • Space launch is effectively powered with electricity from the grid through a battery-storage system pioneered by the company, and in the long term can rely on renewable sources of energy.

Their white paper goes into more detail:

Escape Dynamics’ baseline technology uses a wireless energy transfer system based on millimeter-wave high power microwave sources. The baseline frequency is 92 GHz; however, other mm-wave frequencies (90-170GHz) are also considered. The energy is delivered to the moving vehicle via a phased array of antennas enclosed in proprietary side-lobe suppressing radomes, which ensure safety of the energy transfer.

Our baseline propulsion approach is a thermal thruster which uses hydrogen as a working fluid and a heat exchanger for coupling external microwave energy into the thermal energy of the hydrogen. External microwave energy is absorbed in a ceramic matrix composite (CMC) heat exchanger with dimensions of approximately 3m by 5m. The hydrogen is initially stored as a liquid in a cryogenic tank and is supplied to the heat exchanger via a turbopump designed to raise the hydrogen’s pressure to approximately 150atm. The hydrogen is heated to above 2000C as it flows through the heat exchanger and is exhausted through an aerospike nozzle optimized for a SSTO flight. The heat exchanger also serves as a primary component of the thermal protection system (TPS) during the return from orbit.

Put the Marines Back in Submarines

Thursday, July 23rd, 2015

David C. Fuquea argues that we should put the Marines back in submarines, where they haven’t trained since before Afghanistan and Iraq:

There have been opportunities to put marines back on subs, but they have been missed. The Navy and Marine Corps have recently reoriented back towards amphibious operations after the land-locked conflicts of the last 13 years. Gen. James Conway, during his tenure as commandant, advocated a “return to the amphibious roots of the Corps.” One manifestation of this advocacy was the return to large-scale training events on both the East and West Coasts. The “Bold Alligator” series of exercises on the East Coast began slowly in 2010 with staff-level discussions and culminated in 2012 with the largest peace-time exercise amphibious landings since Exercise Purple Star in 1996. In 2014, United States Navy and Marine forces, along with forces from several nations, executed a second large-scale Bold Alligator exercise off the coast of North Carolina. In 2011, I served as the lead planner within 2d Marine Expeditionary Force for Bold Alligator and recommended strongly that, given the A2/AD threat, a submarine be integrated into the exercise. My discussions with other planners involved with Bold Alligator 2014 indicated that a submarine was once again recommended for inclusion in the large-scale amphibious exercise. Yet, despite the notoriety and scale of these two exercises, not a single submarine was integrated into the amphibious planning for either. With these as the first large amphibious exercises since the late 1990s, and given the complicated nature of water-space management and amphibious operations, the Marine Corps has a generation of planners and senior leaders responsible for amphibious doctrine who have never even contemplated how submarines can execute ship-to-objective maneuver (STOM), ship-to-shore movement (STSM), and over-the-horizon (OTH) operations, and be employed as critical platforms to enable success in an A2/AD environment.

That the platform most capable of surviving the greatest threat facing Marine Corps amphibious operations in the 21st century is not being trained with or planned for means marines may die needlessly. The cornerstone document for how the Marine Corps will conduct modern amphibious operations, Expeditionary Force 21, is less than a year old. With “assuring littoral access” as “the main mission,” the document is rife with examples of the danger to mission accomplishment in the amphibious realm that Anti-Access/Area Denial poses. These A2/AD capabilities “threaten freedom of action at sea.” The document established that the Marine Corps must become proficient at using “alternative seabased platforms” and operating in smaller task-organized forces. The threat from widely proliferated A2/AD systems is so pervasive, Expeditionary Force 21 calls for amphibious forces to stand off from landing sites and objectives at least 65 nautical miles until threats are mitigated. Doctrine requires amphibious vehicles launch from at least 12 miles off shore, despite their anachronistically slow ship-to-shore movement speeds brought from World War II. Even the most modernized versions of the Amphibious Assault Vehicle (AAV) still move to shore at the same speed of their predecessors from the assault on Tarawa in November 1943. The current planned replacement for the AAV will be a wheeled vehicle with even more limited capability to move autonomously from ship to shore. Unfortunately, submarines, the only platforms with the ability to stealthily penetrate the A2/AD screens to be faced, are not even mentioned as an “alternative platform” to be considered for this purpose within Expeditionary Force 21. This conceptual oversight must be addressed and remedied.

The introduction to the fleet of the “guided missile” class of submarines is the perfect tool for amphibious operations in the 21st century, yet is being ignored by the Marine Corps. In 1999, the U.S. Congress funded the conversion of four Ohio-class ballistic missile submarines into guided missile submarines, or SSGNs. At 560 feet long and over 18,000 tons (submerged) in displacement, these “boats” are like their predecessor the Argonaut with far greater capability. The SSGNs have long-term billeting for 66 personnel and, with “hot-racking,” have managed 100 or more embarked personnel for short-term transits. Missile tubes that previously protected our nation through nuclear deterrence now hold a mixture of Tomahawk long-range cruise missiles (TLAMS) and gear for amphibious operations. Two of the former missile tubes have sprinkler systems to afford considerable space for ammunition storage. Remaining storage areas can hold up to 39 inflatable boats (CRRCs), enough for over 200 marines to move from ship-to-shore by this World War II-era conveyance. The SSGNs also have an operations center for embarked troops that rivals those aboard any of the amphibious ships currently at sea in any navy, giving an embarked commander the ability to command and control forces ashore effectively. “Through-deck” connectors allow access while submerged to two Dry-Deck Shelters (DDS) mounted to the exterior deck of the SSGN behind the “sail.”

The two shelters of an SSGN provide over 3000 cubic feet of dry storage for ship-to-shore movement systems for marines. The inflatable CRRC, the most prominent conveyance when marines last conducted submarine training, is an antiquated, anachronistic World War II system — not to mention highly vulnerable in a firefight — and needs to be discarded. While not the vehicle deck of a landing platform dock, the purchase of current off-the-shelf technology can give marines legitimate over-the-horizon delivery capability at high speeds across water, and then transition to a land vehicle with equally impressive performance from the DDS. Mr. David March, who works through Fountain Valley Bodyworks based in Fountain Valley, California, designed and builds the fast amphibian known as the “Panther.” The Panther looks like a jeep but combines a V6 engine with a conventional water-jet to give highway-speeds on land and over 40 miles per hour on water. On a single tank of fuel, builders of the Panther have documented ranges of 60 or more miles on water, followed by equal ranges on shore. A second off-the-shelf platform for use — equally innovative and viable — is the Gibbs Quadski. This vehicle resembles a standard 4-wheeled all-terrain vehicle (ATV). The Quadski, however, can transition from land to water mode in approximately five seconds. Capable of 45 miles per hour on land and water, the Quadski is designed for one passenger but can accommodate two and sells for approximately $40,000. Marines launching from an SSGN with these types of vehicles would have speed and range to get to the shore from OTH, mobility once they arrive, and fire power inherent in being able to carry crew-served weapons on a vehicle. Employing the critical technique of “maneuver warfare” and landing where the enemy is not, small-mobile-fast Marine units with substantial firepower would have legitimate combat capability to a scale and scope exceeding the size of the unit by an order of magnitude. Additionally, the ability to drive out of a DDS directly into the water equates to much greater safety for the submarine, as compared to marines toiling on the deck inflating CRRCs while the sub waits to submerge again. The DDS would provide space for at least two, perhaps four, “Panthers,” allowing the insertion of up to 16 marines simultaneously. Unfortunately, this type of innovative thinking is not being considered in the operational Marine Corps.

He seems most concerned that various special operations forces are taking over this role.

Water Displacement, 40th formula

Tuesday, July 14th, 2015

WD-40 has an interesting history:

WD-40 was developed in 1953 by Norm Larsen, founder of the Rocket Chemical Company, in San Diego, California. WD-40, abbreviated from the phrase “Water Displacement, 40th formula”, was originally designed to repel water and prevent corrosion, and later was found to have numerous household uses.

Larsen was attempting to create a formula to prevent corrosion in nuclear missiles, by displacing the standing water that causes it. He claims he arrived at a successful formula on his 40th attempt. WD-40 is primarily composed of various hydrocarbons.

WD-40 was first used by Convair to protect the outer skin and, more importantly, the paper-thin balloon tanks of the Atlas missile from rust and corrosion. These stainless steel fuel tanks were so thin that, when empty, they had to be kept inflated with nitrogen gas to prevent their collapse.

WD-40 first became commercially available on store shelves in San Diego, California in 1958.

LED Grow Lights in Space

Sunday, July 12th, 2015

A recent study demonstrated that targeted LEDs could provide efficient lighting for plants grown in space:

Research led by Cary Mitchell, professor of horticulture, and then-master’s student Lucie Poulet found that leaf lettuce thrived under a 95-to-5 ratio of red and blue light-emitting diodes, or LEDs, placed close to the plant canopy. The targeted LED lighting used about 90 percent less electrical power per growing area than traditional lighting and an additional 50 percent less energy than full-coverage LED lighting.

The study suggests that this model could be a valuable component of controlled-environment agriculture and vertical farming systems in space and on Earth, Mitchell said.

I’m reminded of William Gibson‘s aphorism that “the street finds its own uses for things.” LED grow lights have been used here on Earth for not-so-noble purposes for some time, I’d assume.

Solar Saudis

Wednesday, July 8th, 2015

For decades Saudi Arabia has been a poster child for fossil-fuel waste:

The government sells gasoline to consumers for about 50 cents a gallon and electricity for as little as 1 cent a kilowatt-hour, a fraction of the lowest prices in the United States. As a result, the highways buzz with Cadillacs, Lincolns, and monster SUVs; few buildings have insulation; and people keep their home air conditioners running — often at temperatures that require sweaters — even when they go on vacation.

Saudi Arabia produces much of its electricity by burning oil, a practice that most countries abandoned long ago, reasoning that they could use coal and natural gas instead and save oil for transportation, an application for which there is no mainstream alternative. Most of Saudi Arabia’s power plants are colossally inefficient, as are its air conditioners, which consumed 70 percent of the kingdom’s electricity in 2013. Although the kingdom has just 30 million people, it is the world’s sixth-largest consumer of oil.


The Saudis burn about a quarter of the oil they produce — and their domestic consumption has been rising at an alarming 7 percent a year, nearly three times the rate of population growth. According to a widely read December 2011 report by Chatham House, a British think tank, if this trend continues, domestic consumption could eat into Saudi oil exports by 2021 and render the kingdom a net oil importer by 2038.

That outcome would be cataclysmic for Saudi Arabia. The kingdom’s political stability has long rested on the “ruling bargain,” whereby the royal family provides citizens, who pay no personal income taxes, with extensive social services funded by oil exports. Left unchecked, domestic consumption could also limit the nation’s ability to moderate global oil prices through its swing reserve — the extra petroleum it can pump to meet spikes in global demand. If Saudi rulers want to maintain control at home and preserve their power on the world stage, they must find a way to use less oil.

Solar, they have decided, is an obvious alternative.

Well, they do get plenty of sun:

In addition to having some of the world’s richest oil fields, Saudi Arabia also has some of the world’s most intense sunlight. (On a map showing levels of solar radiation, with the sunniest areas colored deep red, the kingdom is as blood-red as a raw steak.) Saudi Arabia also has vast expanses of open desert seemingly tailor-made for solar-panel arrays.

Solar-energy prices have fallen by about 80 percent in the past few years, due to a rapid increase in the number of Chinese factories cranking out inexpensive solar panels, more-efficient solar technology, and mounting interest by large investors in bankrolling solar projects. Three years ago, Saudi Arabia announced a goal of building, by 2032, 41 gigawatts of solar capacity, slightly more than the world leader, Germany, has today. According to one estimate, that would be enough to meet about 20 percent of the kingdom’s projected electricity needs — an aggressive target, given that solar today supplies virtually none of Saudi Arabia’s energy and, as of 2012, less than 1 percent of the world’s.

I suppose that’s one way to address the problem:

In October, the World Bank estimated that Saudi Arabia spends more than 10 percent of its GDP on these [energy] subsidies. That comes to about $80 billion a year — more than a third of the kingdom’s budget.


Aramco sells oil to the Saudi Electricity Company for about $4 a barrel, roughly the cost of production. Even with the global price of oil down to about $60 a barrel as of this writing (a drop of about 40 percent since June 2014), Saudi Arabia forgoes some $56 on every barrel it uses at home. That gap will become far greater if, as many experts expect, the global price rebounds.

The F-35 Can’t Dogfight

Tuesday, July 7th, 2015

It comes as no surprise that the F-35 can’t dogfight, according to a recent test pilot’s report.

Harvard Gets Its Geek On

Tuesday, July 7th, 2015

Harvard’s Paulson School of Engineering and Applied Sciences has seen its enrollment increase dramatically since it became its own school in 2007. Harry Lewis, its interim dean, explains what’s driving demand:

The easy answer is we’re doing a superb job of teaching our courses and we’ve created an infectious enthusiasm among undergraduates. And I think that’s all partly true — CS 50 [the introduction to computer science] is a cultural phenomenon at Harvard now, in a way that never used to be the case. People take CS 50 because their buddy on the lacrosse team is taking the course. Everybody knows it’s a cool course, so everybody wants to take it. The same thing is happening to a lesser degree in some of the other engineering disciplines.

There’s also been a kind of cultural change at Harvard, where making things, doing useful things, is no longer — as it certainly once was at Harvard — considered the sort of thing gentlemen and gentlewomen didn’t do. Harvard used to be a place where pure science was revered and applied science was not particularly respected. And that’s very much not the case now.

I’m sorry, gentlewomen? Really?

Kindle Paperwhite

Wednesday, June 17th, 2015

Kindle PaperwhiteThe new Kindle Paperwhite, announced today, has a 300 ppi display. Should I finally get one?

I Made an Untraceable AR-15 ‘Ghost Gun’ in My Office — And It Was Easy

Monday, June 15th, 2015

Andy Greenberg decided to make an untraceable AR-15 ghost gun — that is, to finish off an 80-percent-finished AR lower, which isn’t legally a gun yet — three different ways:

I would build an untraceable AR-15 all three ways I’ve heard of: using the old-fashioned drill press method, a commercially available 3-D printer, and finally, Defense Distributed’s new gun-making machine.

The Martian

Thursday, June 11th, 2015

I’ve been meaning to read The Martian, but xkcd may have just given me the push I needed:

xkcd The Martian