Month: November 2017

Slanting a story to the point of lying

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Caught this story by the Financial Times and was shocked at the lengths the “reporter” went misinform the public. To be fair, perhaps Peter Campbell and Nathalie Thomas are just that ignorant, but if that is the case, they should not be reporting on stories like this.

Problems started with the headline:

Tesla truck will need energy of 4,000 homes to recharge, says study

Wow, the energy of 4,000 homes to power a single truck? That is staggering. Or is it? The key data point missing from the headline is the time factor. Energy for 4,000 homes for how long? Well, quick back of the envelope math tells me that assuming they were talking about the long range truck, which has a 1,000 kWh battery, we are at 250 watt-hours per home. So, how long will 250 wH last in a U.K. home? That depends on how much the home consumes. According to the Office of Gas & Electricity Markets, The average U.K. home consumes between 1,900-7,100 kWh per year. If I take the median value of those numbers, I get 4,500 kWh, or 12.3 kWh per day, or roughly 513 wH per hour. Based on those assumptions, we are running our 4,000 homes for less than 30 minutes.

Now, the energy to run 4,000 homes for just less than a half hour is an impressive amount of energy, but now we have context to our numbers, something the original headline did not convey. If I chose, I could have used the same absence of time context to make the headline “scarier” by using the lowest value of electrical consumption from OFGEM, run them for only a second, and then written:

Tesla truck will need energy of 15.9 million homes to recharge, says study

Way scarier headline, and just as true as the first one.

Okay, off to a bad start. Let’s go with the first three paragraphs:

One of Europe’s leading energy consultancies has estimated that Tesla’s electric haulage truck will require the same energy as up to 4,000 homes to recharge, calculations that raise questions over the project’s viability.

The US electric carmaker unveiled a battery-powered truck earlier this month, promising haulage drivers they could add 400 miles of charge in as little as 30 minutes using a new “megacharger” to be made by the company.

John Feddersen, chief executive of Aurora Energy Research, a consultancy set up in 2013 by a group of Oxford university professors, said the power required for the megacharger to fill a battery in that amount of time would be 1,600 kilowatts.

Here some context is implied, if we assume 30 minutes is the time the are talking about our 4,000 houses running, and we use that median consumption value of 4,500 kWh per year. But the article doesn’t tell us this, violating the first rule of math: “show your work”.

We are then introduced to this John Feddersen chap and his four year old consulting company made up of some Oxford professors. We are not told who Aurora Energy Research is funded by, their purpose, or the academic disciplines of these professors. When I popped over to AER’s web site I found that they are, in fact a consulting firm, with 15 directors, whose academic expertise consisted of eight economists, three business admins, one mathematician, one philosophy/French major and one mechanical engineer. What was completely lacking from a consulting firm that specializes in the entire spectrum of energy generation would be anyone with actual engineering expertise in any of the relevant fields. How much weight do I give Mr. Feddersen’s opinion on the technical aspects of Tesla’s batteries, chargers, and drive trains when he is an economist. not an electrical, chemical or materials engineer?

Tesla declined to comment on the calculations.

Well, one can understand why Tesla will not take time out of its busy schedule to rebut the opinions of people lacking the expertise to understand the rebuttal.

Mr Feddersen used the example of the Tesla truck to highlight the need for greater debate around how grid infrastructure will need to be adapted to meet demand for electric vehicles.

“There are smart and dumb ways to incorporate this level of capacity requirement into the system, but either way, fully electrified road transport will need a large amount of new infrastructure,” he told the Financial Times.

Certainly true. Also true: There are smart and dumb ways to write an article about this subject, but either way you need competent reporters talking to actual experts in relevant fields in order to write them.

National Grid, which oversees Britain’s electricity system, has suggested that in the most extreme scenario, electric vehicles could create as much as 18 gigawatts of additional demand for power at peak times in the UK by 2050.

Right, so what are the other scenarios? The more realistic ones that are not “the most extreme”? In the most extreme scenario I can foresee, a previously undetected asteroid the size of the moon could slam into the Earth in the morning and annihilate all human life on the planet. However, should I plan my breakfast cereal purchase according to that scenario, or a more reasonable one that involves being around to eat my Fruit Loops™?

Industry experts believe strains on the system could be reduced by using “smart chargers” that only re-boot vehicle batteries when the grid is able to cope, rather than at peak times, such as after work.

One “recharges” vehicle batteries, one does not “re-boot” them. And that, boys and girls, says all we need to know about the “expertise” of this article.

Tesla Semi Rolled Out to Enthusiastic Crowd

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At an event reminiscent of Steve Jobs rolling out the iPhone, Elon Musk showed off his new Tesla semi, a vehicle that, if it delivers on half of its promises, can remake the trucking industry.

Typically for Musk, the event started about 40 minutes late, but as usual he did not disappoint.

Musk introduces Trucking: The Next Generation

The sight of a massive tractor-trailer moving onto the stage in almost complete silence was surreal. Aside from the typical Tesla “look”, two things jumped out to the observer. The rear wheels of the truck where completely shrouded to reduce drag and the driver’s seat was centered in the cab as opposed to the usual left-hand location. Musk claimed this was a “safer” way for the driver to sit. I will leave that claim for auto engineers to evaluate, but one immediate advantage to that design is it eliminates the need to have separate assembly lines for right-hand/left-hand drive vehicles. This truck can be sold anywhere in the world.

All right, let’s get to the specs:

Range: 500 miles

Performance: 0-60 in 5 seconds. 20 seconds will full 80,000 lbs load, 2 kWh per mile.

Drive system: 4 independent motors, allowing the truck to continue moving even if two of its motors fail.

Recharge time: 400 miles in 30 minutes using a new Tesla “Megacharger”

Safety: Enhanced Autopilot providing lane keeping, emergency breaking, collision warning and anti-jacknifing software, and hardened windshield glass (resistant to breakage and cracking)

Warranty: (Should be said in Doctor Evil’s voice) 1 MILLION miles.

No specs so far on battery size and some unconfirmed rumors that the truck would run $200K-$250K with operating expenses 20% cheaper than current trucks, 50% if the trucks travel in “platoon mode”, meaning a convoy. Details on the mechanics of this were missing, but with AP mode and the ability of the trucks to talk to each other, it would be easier to run trucks close together with each truck’s brakes linked to the truck in front of it. Meaning that if a lead truck must brake suddenly, it automatically signals the truck behind to automatically brake as well.

The design of multiple motors to enhance performance and reliability is a masterstroke of engineering, and something not really practical, or economical, on a diesel rig. Electric motors are small, yet very powerful, so Tesla has one driving each wheel on the rear axles. Since the motors are software controlled, performance can be optimized and altered to prevent the rig from “jack-knifing” by altering power to each wheel.

Tesla will have to “show its work” to convince skeptics about a lot of these specs like battery range and charging times, but the rest looks pretty much within Tesla’s capability.

Doing some back of the envelope calculation, I was able to infer a few facts. Tesla claims the semi will expend 2 kWh of electricity per mile, which means that for a truck to have a 500 mile range, will require a 1,000 kWh (1 megawatt hour) battery. The newest, most modern and fuel efficient diesel semi gets 10 mpg, which at $3.00 a gallon, works out to 30¢­ a mile. Tesla is promising that its solar-powered Megachargers will deliver electricity at 7¢ a kWh, which translates into 14¢ a mile.

This is where Tesla will have to convince a lot of skeptics. Can it build a viable charging station powered by a solar array (with battery packs to store power to supplement the station at night and in inclement weather) which can realistically perform as promised? If we take a more realistic rate for grid electricity of 12¢ per kWh (the national average) Tesla still outperforms a standard diesel by 20% (6¢ a mile). But, to be fair we should then use the more realistic average fuel efficiency of 6 MPG for diesel trucks, which drives the price per mile for to 50¢ a mile, leaving the Tesla again with roughly 50% less fuel cost.

Tesla has zeroed in on the main issues of importance to freight haulers: Operating cost and keeping trucks moving. An electric motor will always outperform its internal combustion counterpart by at least a factor of two and electricity is more ubiquitous, easier to make, and safer to be around, compared to diesel. In order to make money, a truck must be on the road as and moving as much as possible. A truck that isn’t moving due to a cracked windshield, a motor/transmission/emissions problem, or an accident is a truck losing money.

Tesla has addressed all of these challenges elegantly and economically.

And since no reveal with a Steve Jobs flavor would be complete without “Oh, and one more thing…” Musk ended his presentation, went to black as his trucks pulled off, then lit the overhead screen with “plaid” graphics, while his truck silently backed up and disgorged its cargo of one Tesla Roadster, Mk II.

The car was stunning, but the specs were definitely something Tesla critics will want proven to them. The base model promises “Plaid” mode, 0-60 in 1.9 seconds, 0-100 in 4.2 seconds, with a top speed of 250 MPH. Next we get to things that are really difficult to believe. First is a 200 kWh battery promising 620 miles for range. The second, and certainly most difficult to accept is that the Roadster is a 4 passenger vehicle. I think they are definitely using a flexible definition of passenger as in person larger than 5′ tall or weighing more than 100 pounds.

And with those caveats, let the debate begin.

Update: Here is a synopsis of the even from The Verge:

About that EV tax credit…

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The plan by the tax cut happy GOP to eliminate the EV tax credit is chock full of hypocrisy and double dealing. “Hey, let’s cut some taxes. First up, we eliminate a tax credit that has been benefiting U.S. consumers and U.S. automakers!”

Sheesh. I am perfectly happy to stipulate the sincere objection some fiscal conservatives might have to “subsidizing” certain segments of the market because that puts the government in the position of “picking winners and losers”. However, that objection loses a lot of validity if the same group making it then turns around and advocates paying a subsidy to coal and nuclear industries because they cannot compete economically with the modern energy systems that are cheaper and cleaner. That would seem to me to be “picking winners and losers”, and rather hypocritical.

Also, an argument can be made to cap the EV tax credit to cars costing less than $40,000, since that is far enough above the median new car price to account for the expense of new technology, while low enough so as not to give tax credits to people who don’t really need them. If you can drop $75K+ on a new car, you are in an income bracket that can afford to give the tax credit a miss.

I would also accept converting the tax credit into a “point of purchase” rebate so that people in the lower tax brackets who would not benefit from the credit (by virtue of not owing enough federal tax) could offset the cost of a new EV. Heck, I would also say that we should offer a lesser credit for used EVs, say $1500.

No matter where you fall on this issue, I believe that we should agree that fiscal conservatives can’t have it both ways. If you don’t like subsidies/credits/incentives, then ban all of them. If you are going to let legacy manufacturers and energy producers have them, then new manufacturers and energy producers get them too.

Greensboro Buying 4 eBuses for $3.8 Million

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Greensboro to buy 4 battery-powered buses
News & Record

The city will spend $3.8 million on four battery-powered buses, which will join the transit system’s fleet this summer.

The purchase will make Greensboro the first city in North Carolina with all zero-emission, battery-electric buses.

The new buses will replace diesel buses that have been driven past the recommended 12-year, 500,000-mile life. Officials estimate that each new bus will save taxpayers $325,000 over their lives, since they use less energy and need less maintenance than the diesels.

The city will pay for the buses with money from the transportation bond that voters passed in 2016, along with federal and private grants.

Meanwhile, in the dark of night, our own intrepid chemical engineer, Dr. Vernon Gilliat, spotted this marvel of engineering near the Thomas Built Bus plant.

eBus made by Thomas Built Bus of High Point, NC