MTBE

Methyl tertiary butyl ether is what is known as an “oxygenated hydrocarbon.” For reasons that still weren’t clear the last time I checked, oxygenated hydrocarbons alter the combustion characteristics of gasoline in an internal combustion engine such that combustion is more complete and in particular, carbon monoxide is reduced. Carbon monoxide incidents are more numerous in winter (because atmospheric ventilation rates are lower), so oxygenated fuel additives have been mandated for winter gasoline blends.

Oxygenated hydrocarbons are also generally octane boosters. In fact, ethanol, the alternative oxygenate to MTBE, was originally considered promising as an octane additive in the early days of the automobile. One story as to why tetra ethyl lead became the gasoline octane additive of choice is that ethyl could be patented, while ethanol could not. Another suggestion is simply that ethanol is not generally made from oil, and oilmen didn’t want it in gasoline for that reason.

For whatever reason, I can say from personal experience that the attitude toward ethanol among managers in the petroleum industry is very close to foam-at-the-mouth psychotic. They really, really, hate ethanol. MTBE, on the other hand, is made by the oil and gas industry (from natural gas to methanol to MTBE), and oilmen loved it.

From an environmental standpoint, you could say that MTBE is good for the air and bad for the water. Specifically, MTBE, like ethers generally, is water soluble, and will move into groundwater pretty easily. It also has a characteristic flavor and odor, which is apparently detectable (and unpleasant) in very small concentrations in drinking water.

None of this information is new; it was certainly well known 25 years ago, when MTBE was first being touted as an “environmentally friendly” additive to gasoline. It was, from the start, a big part of the “reformulated gasoline” initiative, whose intent was to bring some environmental awareness kudos to the gasoline industry, and, incidentally, to create a bit of a refinery squeeze to drive some independent filling stations and chains out of the market, or to at least bring them into line.

But everyone was aware of the potential problem of groundwater contamination, especially from leaks in service stations’ underground storage tanks. In fact, the industry had an answer to this problem: double walled storage tanks. There was a certain amount of underground leak contamination anyway, and this was touted as the solution to it. And again, it had the additional benefit of being expensive enough that it would drive some marginal independent stations out of business, again squeezing the supply chain.

So the idea was to retrofit the storage tanks before MTBE was adopted. Unfortunately this didn’t happen. While one part of the petroleum industry was confidently lobbying to put MTBE in, and it won’t be a problem because we’ll have underground tanks to keep the stuff from leaking, another part of the industry was lobbying to delay, delay, delay the storage tank replacement program, because it would cost them money. Often you had lobbyists from the same company arguing both cases, though, it should be admitted, rarely on the same day, or at least not to the same people.

So that, more or less, is how Santa Monica came to lose 70% of its drinking water to MTBE contamination, why Santa Barbara had to spend millions on a new water treatment plant, and why a lot of people across the land came to be really pissed. It also played a role in the current fad for ethanol fuels (I give that one another two or three years, tops) but that's a story for another day.

Electric Cars

I haven’t seen “Who Killed the Electric Car?” a documentary directed by Chris Paine about the EV1, a General Motors electric automobile that was withdrawn from (limited) production in the late 1990s, after a California Air Resources Board rule mandating some “zero emission vehicles” was rescinded. That doesn't mean I don't have opinions about the matter, of course.

There’s been a fair amount written about the entire affair, and I’ll only add the point that I suspect that one major factor was never addressed by the filmmakers or anyone else. In every large organization, the major decisions at the top have more to do with personal infighting amongst the managers than anything external. There were people pushing the project, for a variety of reasons, including some who wanted it sabotaged from the beginning, and they got their way. To whatever extent it was a con job designed to demonstrate that there was no market for electric vehicles only underscores the point. The GM divisions that were making big bucks selling gas guzzlers were never going to let an alternative vision get a fair hearing; the eventual fate of the Saturn is a good demonstration of the phenomenon.

Nevertheless, we do have some electric cars on the road now, though they are called “hybrids” and they burn gasoline in a motor to generate electricity that then runs electric motors to power the drive train. Some versions of the hybrid have the gasoline engine connected directly to the drive train and use the electric motors to add power when needed, and to recharge the batteries when the drive demands are less than the gasoline engine output.

A major part of the deal with hybrids is to greatly narrow the operating conditions of the gasoline engine. Under constant, optimized load conditions, you can finely tune the engine performance to maximize fuel economy and minimize emissions of pollutants. The other secret of any electric engine is that it can use “regenerative braking,” i.e., when the car slows (or if you’re going downhill), the electric motors become electric generators and you can recapture and store a substantial amount of the vehicle’s kinetic energy back into the batteries.

Having the internal combustion (IC) motor available finesses the major drawback of electric vehicles, limited range. Typically, EVs only manage less than 100 miles on a full charge, and take substantial time to recharge (1-15 hrs). Hybrids have the full range of gasoline powered vehicles.

The next obvious step in the development pathway is the “pluggable” hybrid, which allows the vehicle to be brought up to full charge from an external electrical source (and there would be a larger battery pack, bringing the thing closer to the true electric vehicle in electric storage). For a substantial number of commuters, the IC engine would seldom need to be engaged; one fellow who has “hacked” his Japanese hybrid claims that his overall fuel efficiency is over 100 MPG, though that doesn’t take into account the fuel burned to produce the pluggable power. (Actually, I seem to recall that he has home solar power panels, so he’s just the greenest of the green, isn’t he?).

Some environmentalists (and some fake environmentalists who carry water for the energy industry status quo), argue that electric vehicles merely shift the power generation (and pollution) elsewhere. That ignores the fact that IC engines operate at a pretty low thermodynamic fuel efficiency (the efficiency of converting the heat of combustion of the fuel to motive force, ignoring losses in the drive train), generally around 25%, though highly optimized, high compression engines can exceed 30%. By contrast, ordinary steam turbines generally start at 40% efficiency, and combined cycle and other tricks make more modern large stationary plants as much as 55% efficient.

It’s also considerably easier to manage pollution control from a single, large point source (whether the regulatory process manages to accomplish this is another story), and there is some hope that such things as geological sequestration of combustion CO2 might reduce the greenhouse gas emission from such facilities as well. Such tricks are pretty well out of the question for mobile vehicles.

Then there is the matter of the impending changeover from fossil fuel driven electric power generation to renewable sources. Wind power is already economically competitive to fossil fuels in many circumstances, and will become more so as the greenhouse gas "externalities” (economist-speak for “beggar thy neighbor”), are rationalized. As a scientist and engineer, I’m also a fan of nuclear power; I just don’t trust our current industrial oligarchy to do it in anything like a safe and sane manner.

There is also the photovoltaic option. The overall field and the statistics behind it are pretty slippery, but it looks like the cost per peak watt for photovoltaics have been halving at something like 5-10 year intervals, while the install capacity has been going up more dramatically, as each price reduction opens up a larger market. Also, in contrast to the U.S., Europe and Japan have been using regulatory action, subsidies, and guaranteed market tactics to encourage alternative energy, rather than discourage them. (In the U.S., a giant game of “crack the whip” has some governmental entities attempting to encourage alternate energy sources, while other entities penalize them, which is a good way to generate paralysis and wasted development efforts).

If you put photovoltaic cells on an automobile, you don’t get a “solar car” in the sense of being able to run on sunlight alone, but (the last time I did the calcs anyway), you do get the equivalent of about 10-20 miles per day of solar driving in the sunbelt areas of the country. That’s not trivial in terms of oil consumption; on average, it could reduce the fuel consumption of a hybrid by around 15-25%. If you’re already driving to work on the charge you got the night before, you’re down to needing maybe a half-gallon of gasoline per day on your daily commute.

That looks like the natural channel for the technology to follow, but there are plenty of things that can screw up a lovely vision of the future, including those who just plain want to keep everything “under control.”

Birth of a Catchphrase

In 1978, I bought a new car, the only dealer-new car I’ve ever bought. I drove it for the next twenty years.

It was a Honda Civic, two doors, with a luggage rack on top that I used a number of times. I didn’t carry a weight equivalent to the car, but it sometimes felt like it. It got 35-40 miles per gallon, doubtless assisted by the fact that for much of the time, 55 was the speed limit, and I didn’t drive much above the speed limit, because I got the 4 speed model.

I got the Honda in part because I was impressed with the engineering of the CVCC engine. I’d just recently done a survey on nitrogen oxide emissions into the atmosphere, and part of that involved reading a lot of Society of Automotive Engineers publications on IC engines and emissions. The CVCC stratified-charge engine was one of the most intrinsically clean designs ever, low in hydrocarbons because it was “lean burn” but also low in NOx because of a very clever “slowly moving flame front” technique they’d developed, that kept the NOx from being “frozen out” by a sudden quench in combustion temperature that usually went along with the IC cycle.

Of course, the low emissions thing kinda stopped when I finally blew one of the valves and began running the thing on three cylinders for the last 18 months of its life.

Anyway, my own personal auto has been a Honda since that first one; Amy drives a minivan, because here show has a lot of stuff in it, and besides, minivans are handy for cross country trips. Still, I drove more times across the country in my ’78 Honda than I’ll probably ever do again.

I got my most recent Honda Civic about five years ago, and I didn’t drive it much for a couple of weeks, because I still hadn’t gotten rid of the previous one. When I finally did make the changeover, I noticed an odd smell in it, something that hadn’t been obvious when I originally test drove it. It took me a day or two to investigate, and when I did, I found a dead catfish under the driver’s seat.

I surmised that the last trip by the previous owners had been to go fishing, and one of them had “gotten away,” just not into the water. So it lay under the seat, probably buried in whatever freshener they’d used as part of the “clean the car so we can sell it,” endeavor. But the time I touched it, the catfish had gone slimy and, well, pretty disgusting, really. I got some paper towels to pick it up, then tossed it into some bushes behind where I worked. I looked for it the next day, but it was gone, I assume to some animal, domestic or otherwise. My workplace bordered a Bay Area Nature Area.

It took no small amount of effort to clean up the residue. I used soap, ammonia, vinegar, and bleach in sequence (not together, I’m quite aware of the hazards of ammonia and bleach), as well as substantial amounts of rinse water. The smell still lingered for a week or so, but then faded.

Some people say about some minor boon, “Better than a poke in the eye with a sharp stick.” I sometimes say, “Better than a dead catfish under the driver’s seat.” If you ever hear anyone else say that, they got it from me.