Thursday, December 27, 2007

Hurricanes -- Whither Thou Blowest?

New Orleans scene, post-Katrina

When one is born and raised in New Orleans, the fear of hurricanes is never far away. And though I left the city after high school, the fear was certainly rekindled after Katrina and after family members and friends lost so much. Now, some 28 months after this cataclysmic event, what do we really know about hurricanes? Can they be predicted? Are they getting worse? 

I’m not going into the various theories that are actively being studied by climatologists and meteorologists around the world, particularly the impact of climate change and warming ocean water temperatures on hurricane frequency and severity. I’m not going into them because (a) it’s not my field, and (b) the theories are still just that – they’re yet to be proved. Few subjects of scientific inquiry have as many variables and as intractable solutions.

Rather, I’d like to look at recent predictions and at the long-term frequency of major hurricanes. Both the forecasts and the hurricane activity data are available from the
 National Hurricane Center.

The hurricane season is June through November. In May of each year, the National Oceanic and Atmospheric Administration makes its forecast for the upcoming season, and in December issues a report on the actual results.

In 2005, the devastating year of Katrina and Rita, NOAA’s May report predicted “… a 70% chance of above-normal hurricane season... with 3-5 major hurricanes.” A major hurricane is defined as category 3, 4 or 5, with winds above 111mph, 131mph, and 155mph, respectively.

Good call. There were seven major hurricanes in the Atlantic basin, with four land-falling U.S. hurricanes. One of the worst years ever.

Then, in 2006, the May forecast called for another horrific season, with “… an 80% chance of an above-normal hurricane season… and 4-6 major hurricanes.” As it turned out, the prediction was dead wrong. From the December report of NOAA: “The 2006 season saw no land-falling hurricanes in the continental United States.”

In 2007: “75% chance of above normal…3-5 major hurricanes.” The results? There were two majors, but neither made U.S. landfall.

Perhaps NOAA’s forecasting record is best summarized in this quote from a 1997 report of the Department of Atmospheric Sciences of Colorado State University, one of the nation’s leading hurricane forecast centers”

“Meteorologists are known to be absolutely brilliant at after-the-fact explanation of weather phenomena…but please don’t press us too hard on future events.” (Which evokes the famous saying attributable to physicist Niels Bohr, “Predicting is difficult, especially about the future.”)

Well, we don’t seem to get much help looking at the last three years: a terrible season, followed by two of the most benign in history. So can we gain any insights by studying long-term hurricane activity? Are there any long-term trends that we can extrapolate into the future?

The following chart shows the frequency of major hurricanes striking the U.S. mainland since 1851, plotted by decade.

Hurr Maj by Decade

The inference from the chart, unfortunately, is that there is no trend to infer. In fact, smoothing the data would yield a curve roughly approximating a sinusoid. That suggests that there is no long-term trend line.

The last decade’s major-hurricane activity has been above normal, but it is still below the peaks of the 1940s through 1960s. And following that thirty-year period of very high activity, major hurricanes declined significantly – to hundred-year lows.

Looking ahead to the 2008 hurricane season, beginning in five months, we’ll get a new NOAA forecast in May that may or may not be prescient, and we’ll have 157 of historical data that may or may not be useful.

So come June 1, once more we’re on our own. Let’s plan for the worst, and hope for the best. As to whom to turn to for clues to the future, I’m reminded of screenwriter William Goldman’s succinct summing up of Hollywood: “Nobody knows anything.”

Mother Nature at Work

Tuesday, December 25, 2007

Car of the Future

Donna and Ben in a Tesla Roadster at the factory in San Carlos, California

Fifteen years ago, my brother
 Harold, (father of the geostationary communications satellite) and I (father of two sons) started a company to build a hybrid-electric powertrain for passenger automobiles. Our goal was to radically improve fuel efficiency, to reduce emissions to trace levels, and to achieve these goals without sacrificing the vehicle’s performance. Indeed, we were promising a high cruise speed, a zero-to-60mph acceleration in under six seconds, and a comfortable interior seating five passengers.

To achieve these ambitious goals in a full-size car, two key components had to be developed.
 Rosen Motors created a magnetically levitated flywheel, while our sister company, Capstone Turbine, innovated a 30kW micro-turbogenerator using just one moving part and turning on air bearings. The flywheel was remarkable, spinning friction free at 55,000 rpm and providing the impressive acceleration. It also recaptured the regenerative braking energy. The microtubine, operating at an efficient and constant 96,000 rpm, was the source of cruise power.`

After four years of development, a Saturn sedan was outfitted with the Rosen Motors powertrain and made its maiden test drive at the
 Willow Springs Raceway in Rosamund, California. The car started, it accelerated, and it ran laps. The flywheel worked, the turbine worked, the car worked. Proof of concept.


But what rhymes with proof is “poof.” During 1996 and 1997, we met with top executive and engineering managements of nine of the world’s major automobile manufacturers. We showed them our theoretical advantages and our actual results. Yet we were unable to convince any of them to invest in and adopt our hybrid technology.

In retrospect, we were too early with the hybrid concept – it was still many years before the Prius arrived on the scene. And we were much too aggressive in our technology choices. Unlike the fast-moving telecommunications and computer industries where Harold and I came from, the auto industry embraces new technology with all deliberate gradualness. I mean really slowly.

And when hybrids did finally emerge from the auto industry, they employed a conventional small internal combustion engine for cruise power and batteries for surge power. No turbines, no flywheels. For Rosen Motors, it was too much, too soon.

So in 1997, we shut down Rosen Motors. But all was not lost. Capstone Turbine is now a public company and the world leader in the nascent microturbine business. And the Rosen Motors flywheel patents are the basis of the
 Pentadyne flywheel storage systems that replace lead-acid battery UPS systems. Rapidly-growing Pentadyne is a leading provider of these clean-energy products.

But back to new-technology cars.

Advances in battery technology over the last decade have created the opportunity for all-electric powertrains to be commercially viable. The pioneering General Motors
 EV-1 battery-powered car of the 1990s failed, among other reasons, because the range was limited by its use of lead-acid and later nickel-metal-hydride batteries.

But with the advent of more efficient lithium-ion batteries, an all-electric car with acceptable range became possible. Indeed, start-up Tesla Motors will start shipping its Roadster, with just under 7,000 lithium-ion batteries powering it, in the first quarter of 2008.


2008 Tesla Roadster

Tesla's lithium-ion-powered concept has already had an automotive industry impact well beyond Tesla itself. Bob Lutz, GM's vice chairman and champion of the radical new plug-in hybrid Chevy Volt, gives this credit to Tesla for the GM project:

"That tore it for me. If some Silicon Valley start-up can solve this equation, no one is going to tell me anymore that's it's unfeasible."

Newsweek, Dec. 31, 2007 issue

The $100,000 Roadster is Tesla’s initial model. Based on the two-seat Lotus Elise sports car, the Roadster will incorporate whiplash acceleration (zero to 60 in four seconds), ticket-garnering high speed (130 mph, electronically governed), and an acceptable 245-mile range. In a few years, Tesla will offer all-electric sedans, and at a lower price.

Because only batteries are used as an on-board energy source, no gasoline -- none -- is consumed. But if one were to convert the energy used by the coal or natural gas at the central power plant to generate the electricity for recharging, it would be the equivalent of 135 miles per gallon. And, of course, there are no vehicular emissions.

To recharge the Tesla from a fully discharged battery, it takes 3½ hours from a 220-volt line, and 11 hours from a 110-volt line.

Video of our visit to Tesla factory Oct. 30, 2007, for a test spin.

Donna and I were early purchasers of the Tesla Roadster – we will get delivery of serial number seven, or more succinctly, 007. And while the car is not inexpensive, I’ve learned that it’s a lot cheaper to buy a car than build a car company.

Delivery was supposed to have been in the summer of 2007; now it's scheduled for first quarter 2008. Which has led some wags to say that Tesla is the car of the future, and always will be. But looking at the world through my Rosen-colored glasses, I'm more sanguine .

Although the Tesla is all-electric, there is still a connection to the Rosen Motors hybrid. J.B Straubel, the chief technology officer of Tesla, was one of the early engineers at Rosen Motors. So, in a sense, our dream of a green, high performance car is finally being realized, albeit in a different form and from a different company.

Wednesday, December 5, 2007

Male vs. Women Swimmers


Well before the 1972 Olympics, in which he won seven gold medal and set seven world records, Mark Spitz (left) established the world record for the 400-meter freestyle (an event he didn’t swim in the ’72 Olympics). His record-breaking time in 1967 was 4:10.6 (shown as 251 seconds on the chart below).

That same year, Pamela Cruse set the women’s 400-meter freestyle world record at 4:36.4 (277 seconds below), or almost 26 seconds slower than Spitz’s time.

Today, some 40 years later, the men’s 400-meter swimmers are still faster than the women, but the gap has narrowed by about four seconds -- the fastest male is just 22 seconds faster than the fastest woman. The fact that the gap is narrowing is only mildly interesting.

But here’s a fact that’s far more interesting: Today’s record-holder in the women’s 400-meter freestyle, Laure Manaudou of France, swims the event faster than Mark Spitz did when he initially set his world record in 1967!


Manaudou’s current world-record time of 4:02.13 (242 seconds in the chart above) for women trounces Spitz’s record time of 4:10.6 in 1967. In a sport where records are usually broken by small fractions of a second, a woman today can swim over eight full seconds faster than the men’s champion did not too long ago. Actually, Spitz’s 1967 time was broken earlier by another woman (Tracey Wickham, Australia) in 1978. So in this event, it took a woman just 21 years to out-swim that legendary hunk, Mark Spitz. Who woulda thunk it?

I’ve used the 400-meter freestyle as just an example to show how women are doing today athletically what men did just a few decades ago. But the swimming stat books are replete with other examples that underscore this point:
Picture 4

So on average, it’s taken about 34 years for women to match the swimming prowess of men. If this holds true in the future, look for the records of
 Michael Phelps (right), today’s version of Mark Spitz and the greatest male swimmer in history, to start being eclipsed by women sometime around 2040. Seems impossible, doesn’t it? But as Satchel Paige said: Don’t look back, something might be gaining on you.