Volkswagen Emissions Issues Spread To Gasoline Cars (bloomberg.com)

schwit1 writes: Just a day after news broke that Volkswagen's emissions scandal had expanded to its Porsche unit and Audi SUVs, the company has disclosed yet another problem, this time affecting carbon dioxide levels emitted by their cars. "Volkswagen said an internal probe showed 800,000 cars had "unexplained inconsistencies" concerning their carbon-dioxide output. Previously, the automaker estimated it would need to recall 11 million vehicles worldwide — more than Volkswagen sold last year." This batch of cars includes a small number of gasoline engines. Until now, only diesel engines were part of the problem.

Comments

Re:bah

[bluefoxlucid]

Catalytic converter burns off unburnt hydrocarbons. SOx is handled by not putting sulfur in the fuel. Burning the fuel colder reduces NOx, but increases CO; burning it hotter reduces CO and unburnt hydrocarbons, but increases NOx. NOx has a really short half-life and a high toxic dose (it's like 12ppb in the air right now and the NIH gets iffy if it hits 1200ppb; health problems start around 1500ppb), but we're panicing more over NOx right now.

People call NOx "pollution", which is a hot button word. NOx is an emission, but not polluting at the elevated levels VW's cars put out. On the other hand, your standard school bus emits lung-irritating particulate and *high* amounts of extremely-toxic CO because it would emit unacceptable (but not harmful) levels of NOx if it burned the fuel hotter, like a VW. I've seen poorly-tuned diesel cars spit out black smoke clouds, and I've been behind a gasoline car that was tuned properly and had a fouled cat--inhaling vaporized hydrocarbons in that concentration made me nauseated; it was like huffing off a jar of high-octane fuel.

That's pollution. That stuff clogs the air and, if every car burned that way, would start wrecking the environment and destroying people's health; NOx emissions like VW as a standard would not fit the government's numbers, but also would not damage the environment. We've been higher before, in the 70s, after catalytic converters became EPA requirements. NOx has a shorter half-life at higher atmospheric concentrations, so doubling the NOx output doesn't really double the amount of NOx in the atmosphere. We'd have less unburnt gasoline and less carbon monoxide in the atmosphere as a trade-off.