Students Build an Electric Car With Better Range Than a Tesla


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Glenn Ong/UNSW Australia Sunswift



Tesla has a new competitor, and it’s not from BMW or General Motors. It’s from Australian university students, whose electric Sunswift eVe set a new world record for fastest average speed—more than 60mph—over 500 kilometers (310 miles) on a single battery charge, on July 23. That’s a big deal: Range is the biggest issue holding back the widespread adoption of EVs, and this record shows the car can drive hundreds of miles at a reasonable highway speed. It stomped on the old record, a mere 45 mph, and drove farther than even the Tesla Model S, the current king of EVs, can go on a full charge.


The eVe is a lovely-looking car whose battery pack can be charged from a regular wall outlet, or using the array of solar panels on its hood and roof. It’s the fifth vehicle made by the students, from the University of New South Wales; its predecessors date back to 1996 and include the IVy, which still holds the record for fastest drive by a solar-powered vehicle at 55 mph, set in 2011.


The eVe is the most practical vehicle the team has produced yet, a big step up from prior versions that were little more than a driver’s seat, three wheels, and a pile of solar panels. It seats two adults and looks more like a regular car than a prototype, though don’t expect the comforts or features found in today’s luxury rides. The eVe is spartan, to help keep its weight to just 700 pounds, less than the battery that powers the Model S. (It’s worth noting the much heavier Tesla can seat seven people and has things like leather seats and air conditioning.)


It takes eight hours to charge the eVe’s 130-pound Panasonic battery using a typical household outlet. Plug it into an industrial port, and it can fill up in five. Sunswift says that if the car is parked in the sun for around eight hours, the 800-watt solar array will provide enough electricity for two hours of driving, plenty to cover the standard commute. The panels can collect energy while the car’s in motion, though not fast enough to replace what’s need to actually drive.


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Daniel Chen, UNSW Australia Sunswift



The drive was made over 120 laps on the 2.6-mile “Highway Circuit” at the Australian Automotive Research Centre in Victoria. A pair of drivers drove in three stints, swapping when the teams did tire changes to avoid fatigue. The panels were switched off because the team wanted to set the record for fastest electric car, and solar-powered electric cars fall in a separate, smaller category.


The test was designed to prove the eVe is ready for practical use, capable of driving hundreds of miles at highway speeds, without recharging. The eVe is a “demonstrator of feasibility,” says Hayden Smith, project director for Sunswift. The team wants to show that solar-electric cars are a “viable alternative to conventional fossil fuel-powered vehicles.” As a student-run university project, the Sunswift team is also focused on training and educating the next generation of engineers through work on a practical project.


The team wants to inspire commercial research into the technology, but also hopes to make the eVe the first road-legal solar-powered car in Australia. That’s a big task, as many parts of the car both internally and externally (think turn signals and headlights) need to be up to code to register it with the proper authorities. The team thinks it’s doable within a year.


The speed record still needs approval by the FIA, the governing body of world motorsport, before it will be official.



Ebola in Africa and the U.S.: A Curation


Daliborlev (CC), FLickr

Daliborlev (CC), Flickr



I’ve stayed out of the Ebola news so far, for a couple of reasons. First, as longtime readers know, I’m writing a book; I’m in the last 6 months of it and the work is intense and involves a lot of travel. I’m not always available at the exact moment news breaks. Second, I try to explore things here that readers may not have heard about elsewhere. The Ebola outbreak has been building in West Africa for a while, but when it was revealed at the end of last week that two American aid workers had caught the disease — and that they were being transported back to the US for treatment — the news and the reaction to it instantly filled every channel. Over the weekend, so much misinformation and outrage got pumped out that it feels as though there’s no way to cut through the noise.


But I have a few thoughts. Start with this: No, I don’t think the two aid workers who are being returned to the US pose any risk at all to the average American, or even the average Atlanta resident. Here’s my marker on that: I’m an Atlanta resident. I live less than 2 miles from the CDC and Emory University (the aid workers are being treated in a special unit housed at Emory on behalf of the CDC; the two institutions are next door to each other). My entire neighborhood and a good part of my various friendship circles are CDC employees, Emory healthcare workers, or both.


(My further marker on this, as longtime readers also know, is that I spent 10 years as a newspaper reporter covering the CDC full-time. I talked my way into outbreak investigations on most of the continents, and embedded with the CDC’s disease-detective corps for a year and wrote a book about it. I am by no means a CDC booster, but I have been with CDC personnel when they made careful, thoughtful decisions about unfamiliar disease risks, including in the anthrax attack on Capitol Hill and during SARS. The recent anthrax lab incident, which was regrettable and sloppy, doesn’t change my mind.)


I base my confidence about the lack of risk to the US in part on the biological reality that Ebola is fundamentally a difficult disease to catch. Contracting it requires direct contact with the bodily fluids — blood, feces, vomit — of someone who is symptomatic with the disease. You cannot catch Ebola from someone who is incubating it but not symptomatic; and you cannot catch it from simply being in the same room as someone who has it. (If you’re going to quote back to me the infamous “airborne Ebola” paper from 2012, don’t bother. Six pigs, four monkeys, engineered lab conditions: no relevance to any real-world situation in a household or a hospital.)


That I am anti-Ebola panic — and especially anti-Ebola media scrum, which was disgraceful — does not mean I am not concerned about Ebola where it is authentically a problem, which is in the expanding epidemic in West Africa. It is a dreadful outbreak, it needs attention, and it says something ugly about us as a society that we only really noticed it when two Westerners were injured by it. But, again: The conditions that are pushing that epidemic along do not exist in the US.


Having said all that, here are a few pieces that I think would be worth your time to read.


Tara Smith at Aetiology on how very over-hyped our image of Ebola is. (That explosive bleeding-out-everywhere thing? Mostly not.)


Michael Osterholm of the University of Minnesota in the Washington Post, on what the world needs to do to control the West Africa outbreak.


Laurie Garrett (who covered past Ebola outbreaks as a newspaper reporter) at CNN, on the African political instability that has made the epidemic so difficult to control.


Declan Butler in Nature, on why the Ebola outbreak will remain a West Africa problem — but not a global one.


David Kroll at Forbes, describing the protections in place at Emory to prevent Ebola spreading.


Helen Branswell at National Geographic, on why there are so few treatments or vaccines for Ebola.


Ren (a semi-anonymous public health worker) at Epidemiological, rendering appropriate disdain to people who said the aid workers should have been left in Africa.


Also, in case you missed it the first time: Me, here at Superbug, on the eight known times that a patient with viral hemorrhagic fever has come to the US, without the disease ever once spreading to someone else.


And finally, two excellent multi-link round-ups: Daily Kos, and Tara Haelle.


This is probably all I’ll have to say on the Ebola situation for a while — unless something changes (or something else gravely annoys me) — so I just want to end by showcasing the comments of the Emory University Hospital leadership on treating the two aid workers. This was sent to Emory staff Sunday afternoon and subsequently posted publicly. It portrays an attitude that I wish we could all adopt as this situation moves forward:



There has been much discussion about bringing patients with Ebola back into our country. Emory University Hospital physicians, nurses and staff can treat them safely and effectively, and we are honored to have the privilege of caring for these patients who contracted Ebola while serving on a humanitarian mission. These two Americans want to come back home and be treated here, and we are committed to helping them. It is our moral obligation to always use our expertise, training, knowledge and gifts to provide such extraordinary care for others.




How Much Does One Lego Piece Cost?


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Rhett Allain



Lego sets come in all different sizes with different numbers of Lego pieces. Of course bigger sets cost more, but is there a linear relationship between set size and cost? Let’s take a look. Oh, and yes – I did look at this before, but that was a long time ago. It’s time to revisit the data.


Lego Price Data


It’s not too difficult to find data for Lego prices and number of pieces. If you just look on the Lego online store. There you can find both the price and the number of pieces for each set. You can even sort them by “themes” – like “Star Wars” or “friends”


Even though it’s easy to get, I only collected price data for a subset of the themes (mostly because I am lazy). If I put all of this data together, I can get a plot of the set price vs. number of pieces in set. Here is what that looks like.


Let’s look at the linear function that fits this data. The slope of this line is 0.104 US Dollars per Lego piece. Boom. There is your answer. On average, one Lego piece costs 10.4 cents. Also, I think it’s nice to notice that this data is fairly linear.


But wait. What about the y-intercept for this fitting function? The value from the fit is 7.34 USD. That means that for this function, if you had a Lego set with zero pieces in it, it would still cost $7.34 – you know, for the box and instructions and stuff. Yes, I know that there are Lego sets cheaper than $7.34 – this is just the y-intercept for the fitting function.


Now let me point out the three outliers in this plot. Notice that all of these (one from Duplo and two from the City theme) are all train sets. Of course train sets are going to be more expensive than a set with the same number of pieces (but not a train) because of the electric motors and stuff.


If you are looking for a “good deal”, might I suggest the Trevi Fountain (21020). This set has 731 pieces for just $49.99. According to the fitting function, a set with this many pieces should cost about 83 dollars.


Which Theme Is the Most Expensive?


Suppose I break all the data into the different themes. If I fit a linear function to each of the different themes, I can get both the price per piece of Lego and the price of a zero piece set.


Here are the brick prices for some of the Lego themes. The error bars are the uncertainties in the fit parameters.


If you know what a Duplo block is, you probably aren’t surprised that they are the most expensive (63 cents per brick). These are bricks created for smaller kids. They are all large so that you can’t swallow them. It just makes since that they would cost more. The other expensive bricks are the City sets. But this is deceiving due to the high set prices of the train kits. I suspect if you removed these train sets from the plot, it would be a more normal price.


What about the base cost? This is the y-intercept of the linear fit.


Here you will notice that the City theme has a negative base cost. This means that if there were no pieces (on average) in a City set, Lego would pay YOU money. But why is this negative? It’s because of the high price of the train sets. They increase the slope of the linear fit but also push the y-intercept into negative values.


The real bargains are the Architecture themed sets. These have a base cost of only 70.7 cents where as the Marvel themed sets have a base cost of 3.61 USD.


Homework


I’ve probably already answered some of these questions in the past, but it would still be fun as a homework assignment. Some of these aren’t too difficult. You could think of them as Duplo Homework.



  • In my linear fits, I did not set the y-intercept to zero. What if you used the data and made fits with a zero y-intercept? What would that do to your price per Lego piece?

  • What about the other themes? Do they have similar prices per piece? Are there any unusually priced themes?

  • If you remove the train sets from the City data, what is the price per piece?

  • If you built a mini-fig scale model of the Death Star, how much would it cost?

  • I heard someone say that there are enough Lego bricks for everyone on the Earth to have 75 bricks. If these bricks were then sold (at a reasonable value) to some alien (off world) traders, how much would they have to pay for all the Earth’s Lego bricks?


Notice that not even once did I use a plural version of the term “Lego”.