Fact-Checking the "PRT Boondoggle" Blog
A project of the PRT NewsCenter

Monday, May 12, 2008

Context Patrol: How much is "trillions"?

Today we return to a subject raised last week. To wit, the Minnesota anti-PRT propagandist's claim:

At the time we pointed out Ken Avidor's claim is rendered absurd by the fact that the entire American economy alone has a value of $10 to 11 trillion. But what degree of absurd? Super absurd? Or mega-über-duper absurd? PRT Is a Joke is a Joke has to nail it down, because that's just how we roll.

Last weekend Public Radio International's This American Life ran a report on the current credit crisis, making much of the fact that the entire pool of money in all the world has a value of $70 trillion. So when Avidor says a Twin Cities PRT network would cost "trillions," how much is that in context?

"Trillions" is plural, so it means more than 1 trillion. At least 2 trillion then. Two trillion dollars is 2.8% of the entire $70 trillion global money supply; 2.8% of all the rice sold in China, everything bought by Bill Gates, all the cars sold by GM, all the songs downloaded at the iTunes Store, all the Slurpees sold by 7-11 -- everything.

Two trillion dollars, out of everything sold in the world. $2 trillion is roughly the GNP of Germany; about the cost of the Iraq war/occupation; the value of the bad mortgages lenders are writing off; the amount Americans spent on health care in 2005. Mr. Avidor expects you to believe a PRT system for one American city would cost that much. Why? The same reason as always -- because he pulls it out of his butt. That's how much he hates PRT.

Also today: Specific World Wildlife Fund support for PRT ("Skycab" thumbnail below orange ball)

Ken Avidor has a mortgaged credibility crisis


A Transportation Enthusiast said...

Oooh, this is a fun game! Let me have a stab at it.

Let's see, the Channel Tunnel is one of the most expensive transportation projects ever undertaken. It cost about $20 billion in 2008 dollars for 31 miles of tunnel. That's $650 million per mile.

Now let's see what $2 TRILLION could build. $2T/$650M = 3075 miles of tunnel. So $2 Trillion would buy a tunnel UNDER THE ATLANTIC OCEAN from New York City to London (~3050 miles).

Or, for the bargain price of $1.5 Trillion, you could tunnel UNDER THE PACIFIC OCEAN from LA to Hawaii (~2400 miles). Or, from Hawaii to Tokeo (4000 miles) for $2.6 trillion.

So Avidor's claim is that PRT in Minneapolis would cost MORE than a bidirectional train tunnel from LA to Hawaii!

Man, that's just too much fun! I want to do more. Let's apply it to Ken's home state and see what we get.

The entire state of Minnesota is about 250mi by 400mi. You could put a 2-dimensional chunnel grid ($650M per mile) across the ENTIRE STATE of Minnesota at 8 mile separation for about $2T!

Now let's do it for PRT. The Taxi 2000 system claims they can build it for $10M per mile. Let's assume they're off by a factor of 5 (doubtful, but let's just see where it goes). $50M per mile means you could build 40 thousand miles of Taxi 2000 guideway, which would cover the ENTIRE STATE of Minnesota at 2.2 mile spacing. So basically every single country road across the state would have a Taxi 2000 guideway, and that's assuming Taxi-2000's estimates are off by a factor of FIVE!.

OK, back to Minneapolis, Ken's hometown. The city is 60 square miles, which we might approximate at 6 miles by 10 miles. But there's surrounding areas too, so let's go 10 miles outside the city in all directions to get the entire metropolitan area. Then we have 26*30 = 780 sq mi. to cover. Again assuming a factor of 5 error in Taxi-2000 estimates, that's a density of .1 mile, or a guideway on every single street in the entire metropolitan area, including side streets! In fact, in suburban areas the PRT network would actually be MORE DENSE than the road network.

Can we all see the utter absurdity of Ken's exaggerations?

jgreene900 said...

To get closer to reality, even to the 'ball park' level, would it help to see how much it would realistically cost to cover the MSP area with PRT? The I-694/494 loop around the cities encloses an approximate 20 x 24 mile rectangle. Placing lines at 1/2 mile intervals gives approximately 2000 miles of guideway (20 X 48 = 960, plus 24 X 40 = 960, for 1920 miles, actually - thank you, Google maps). At $20 million per mile (still twice the estimates, but not quite as conservative as A Transportation Enthusiast), we get $40 billion to cover the core of the metropolitan area. And, this would put every point in that area within walking distance of a station. Trillions? Off by at least a factor of 25!

Mr_Grant said...

Not a bad basic estimate. You can save a couple billion by stopping 1/4 mile from the edge of the 20x24 square, instead of building all the way up to it. I get $37.96 billion.

Strictly speaking, you can also deduct the area occupied by water, parks and other open space. For every sq. mi. saved you can take off about 3.9 miles of guideway.


Mr_Grant said...

Oh, and 38 billion is 1/52 of 2 trillion. -Ed.

Mr_Grant said...

Which is 0.0003846 (0.038%) of the global pool of money. -Ed.

A Transportation Enthusiast said...

Extending on JGreene's analysis...

If each line provides the capacity of a highway lane (a pretty conservative assumption for the Taxi2000 system), every 4 lines on the PRT grid would correspond to a 2-lane (each way) Interstate.

Pushing the math a bit further, that's a 2-lane highway every 2 miles, in both N-S and E-W directions. For a 20x24 grid, this would mean 10 highways going east-west, and 12 going north-south.

They'd run out of numbers!

A look at that area shows about 7 north-south highways and about 4 east-west highways (this does not include city streets). So the $40B PRT system would provide close to quadruple the capacity of the current Twin Cities highway network - with a tiny fraction of the infrastructure needed for highways.

Indeed, a MUCH smaller network would be sufficient for a long time. Conclusion: even the $40B orders of magnitude too high.

Mr_Grant said...

A look at that area shows about 7 north-south highways and about 4 east-west highways

I wonder how many of those highways were 'aggressive'ly championed by Elwyn Tinklenberg?

jgreene900 said...

Yeah, I thought about the 1/4 mile from the edge thing, but figured that, if you could assume $50M/mile for PRT, I could afford a couple extra miles of guideway at $20M/mile!

Though I'm no fan of Mr. Tinklenberg, in his defense, he could have "agressive"ly championed more highways til he was blue in the face, but the checkbook was blocked by the "no new taxes" Republicans. The DOT had been delaying needed infrastructure work for years before and after his tenure. And, that got us a bridge in the river.

Mr_Grant said...

So - Tinklenberg was not only ineffective, he also failed to change the status quo? What a great endorsement! "More of the same -- Vote Tinklenberg"