Month: May 2004

Corrupt Illinois speed zoning practices

A member of Illinois law enforcement who specializes in traffic issues told me that Illinois uses speed display trailers for speed zoning studies.

A little background: the commonly accepted way to set speed limits is to measure the speed of passenger vehicles in a way that is not apparent to motorists. From that speed survey a traffic engineer sets a limit that legalizes most drivers and criminalizes only the fastest, most dangerous drivers.

Speed trailers bias the speed of traffic so that it conforms to the currently posted limit. For example, you will probably slow down if the speed limit sign says 50 but “YOUR SPEED” says 58.

This practice reinforces the currently posted speed limit even where properly run speed zoning studies would have required a higher limit.

What does this mean for the everyday motorist? Ever lower speed limits, causing wider gaps between the fastest and slower drivers, more tickets, and more safety problems.

In a practical sense, the commonly accepted speed zoning practice is usually overridden by arbitrary laws or politics. On nearly every road in the U.S., speed limits are already set so low that nearly everyone is a lawbreaker. Short circuiting speed zoning so that it just reinforces the currently posted limit is a shameful, corrupt, revenue-enhancing practice.

Illinois drivers should be infuriated.

Are gas stoves or ovens more efficient?

Gas appliances supposedly save money. The theory is that it’s cheaper to make a given quantity of heat from gas than from electricity.

Is this really true?

Gas stoves and ovens throw off way more heat than an electric model.

For the stove, this is obvious: the heat from the flames goes across the bottom and then up and around the pan. Electric stoves have a much closer and more direct contact with the pan, so there is much less of this kind of heat loss.

I lived in a house with a 20 year old gas oven for two years. That oven kicked off a huge load of heat. I thought it happened because it was old. I was wrong. A friend’s new gas oven throws off as much heat. The 20 year old electric oven in my current house produces only a fraction of the external heat as those gas ovens.

So that brings us to issue #1: gas ovens and stoves waste much more heat than electrics.

In winter the heat loss is a wash. It is heat that the house’s heater does not need to produce, and it’s produced in an energy efficient manner. But I live in Dallas. We regularly run the heat only around 3 months of the year. The A/C runs regularly at least 6 months of the year. It costs a lot more to remove heat from a house (A/C) than it costs to add heat to the house (heater). Whatever you gain from efficient heating in the winter, you lose through inefficient heat removal in the warm months.

Issue #2: gas ovens and stoves increase the load on your A/C system, which is costly to run.

The big picture is that, per unit of heat consumed, gas ovens and stoves are less efficient than electric equivalents. They lose more heat, and they add to air conditioning costs. The cost of a BTU produced by gas has to be far cheaper than the cost of a BTU produced by electricity for gas appliances to pay off.

Call me a curmudgeon, but I think I’ll stick with electric ovens and stoves. At least that way I can simmer rice without burning it!

Gas dryers, gas central heat, and gas water heaters are a totally different issue. There is plenty of empirical evidence showing that these are more efficient than their electric brethren.

Good news on DEEM

I have been assigned an adviser in the Doctor of Engineering in Engineering Management program. He says that I am probably accepted into the program. It sounds like all that remains are procedural issues, mostly paperwork.

I have already gotten my praxis topic approved. Guess what it is?? Speed limits! My advisor has some experience with traffic engineering, and he showed interest in the subject.

I am so lucky. How many people get to pursue a passion for academic purposes? Now I will have a real excuse to finally thoroughly research this topic.

I-35

Friday was the first time I traveled Interstate 35 between Dallas and Austin, in daylight, in at least 10 years. The normal traffic on I-35 was like I-45 on a busy traveling holiday.

That road’s total right of way seems to be relatively narrow. There is usually only a tiny median between the northbound and southbound inside shoulders. This means that a single careless error can hurdle your 80 MPH car into 80 MPH oncoming traffic. Let’s see, 80 MPH + 80 MPH = really nasty.

In part due to these minimal center medians, TxDOT is erecting stout center barriers on long stretches of I-35. Since most of this wall is new, you can clearly see every impact on it. On one multi-mile stretch I was amazed to see several tire tracks clearly veering into the wall and then bouncing back off. Most of the time the errant vehicle appears to settle in the left shoulder. Sometimes the errant vehicle hits the wall and careens the other way, crossing both lanes and probably running off the right shoulder. Very often the tire marks were of an axle with double wheels on both sides, like with a 18 wheeler or a dually truck.

This barrier upgrade makes I-35 generally superior to German Autobahns. You gotta wonder why the Texas Legislature still arbitrarily caps speed limits at 70 MPH?

At least two small towns had interesting interchanges with I-35 and their main road. Basically I-35 was an underpass in a small canyon that was only wide enough for 2 lanes each way. It looks like this 1950s shot of I-35 in Austin. This kind of interchange is at home on an older US highway, not on the busiest interstate corridor in Texas! When it comes time to widen the roadway, these cities may be in for a surprise.