One of the most polluting and most energy-intensive things we do is to drive our cars and trucks. Gasoline-fueled internal combustion engines are at best about 35% efficient. Most of the time the car is even less efficient, as low as 10-15%, and commonly 25-30%. That means at least two-thirds of the energy in the fuel tank of a car is wasted. Diesels are a little better, but those vehicles suffer from the same inefficiencies: engine heat loss, wind and rolling resistance, braking, friction, idling, etc. You can only get so much useful energy out of an explosion! I should note that Nissan engineers claim they can get 50% thermal efficiency in a gas motor. Right on, I hope it works.

Why should you care about thermal efficiency? The goal of any energy transformation is to make it as clean as possible. To get the most out the resource with the least pain to society. To conserve in the true sense of the word, that of wise use.

Rhodium is the rarest of all non-radioactive metals It is similar to platinum. Ruthenium, palladium, osmium, and iridium are all grouped with platinum because they are all hard and corrosion-resistant. They work well as precious metals and in jewelry, in electronics, dentistry, and most important of all, as catalysts.

80% of the world’s rhodium —this extremely rare precious metal, mind you—is used in catalytic converters.

These devices are great. They really, seriously clean up vehicle exhaust. All of us benefit from this technology. And we should appreciate that there are laws requiring such devices on our vehicles. This stuff makes the air better. We would make the air even better if we drove less, but that it seems is harder to do.

Here’s some cool nerdy stuff about catalytic converters and thus about rhodium, an element you should learn to appreciate.