I've seen a few utterances that certain engines can leave the air more clean than the air going in. I've always thought it was hyperbole. This weekend I came across this link by accident, and it supports this claim.
Link
Quote:
Remember that crazy-expensive lab equipment that measures exhaust emissions? It also measures the emissions makeup of the ambient air that the vehicles draw in through their intake tracts. This is important because, well, what if your emissions lab was located next to a natural gas vent? Only by measuring what goes into and out of the vehicle and comparing the differences can the vehicle's contribution to emissions be accurately assessed.
Here's why you should care. When the Raptor (and the Fiat) was running Phase 2 of its tests on the dyno, it was cleaning the air of hydrocarbons. Yes, there were actually fewer hydrocarbons in the Raptor's exhaust than in the air it — and we — breathed. In the Raptor's case, the ambient air contained 2.821 ppm of total hydrocarbons, and the amount of total hydrocarbons coming out the Raptor's tailpipe measured 2.639 ppm.
Moving on... what about emissions of OPE? I've always assumed that OPE was more dirty, and that an hour of yard work might emit more than a week of commuting. This doesn't fully answer the question, but it doesn't undo my assumption either.
Quote:
Distilling the above results, the four-stroke Ryobi leaf blower kicked out 6.8 times more NOx, 13.5 times more CO and more than 36 times more NMHC than the Raptor.
The two-stroke leaf blower was worse still, generating 23 times the CO and nearly 300 times more NMHC than the crew cab pickup. Let's put that in perspective. To equal the hydrocarbon emissions of about a half-hour of yard work with this two-stroke leaf blower, you'd have to drive a Raptor for 3,887 miles, or the distance from Northern Texas to Anchorage, Alaska.
Now, a leaf blower isn't the same as a lawnmower, but lawnmowers tend to be larger engines, so, maybe they pollute more? Dunno. And something I didn't see mentioned in the article was evaporative emissions. Cars emit very low evaporative emissions. Just sitting there OPE can be "outgassing".
Lastly, the article does briefly mention carbon dioxide, but just for the record, CO2 tracks fuel burn. So we all know how that works (burn more gas, make more CO2, nothing astounding there).
Link
Quote:
Remember that crazy-expensive lab equipment that measures exhaust emissions? It also measures the emissions makeup of the ambient air that the vehicles draw in through their intake tracts. This is important because, well, what if your emissions lab was located next to a natural gas vent? Only by measuring what goes into and out of the vehicle and comparing the differences can the vehicle's contribution to emissions be accurately assessed.
Here's why you should care. When the Raptor (and the Fiat) was running Phase 2 of its tests on the dyno, it was cleaning the air of hydrocarbons. Yes, there were actually fewer hydrocarbons in the Raptor's exhaust than in the air it — and we — breathed. In the Raptor's case, the ambient air contained 2.821 ppm of total hydrocarbons, and the amount of total hydrocarbons coming out the Raptor's tailpipe measured 2.639 ppm.
Moving on... what about emissions of OPE? I've always assumed that OPE was more dirty, and that an hour of yard work might emit more than a week of commuting. This doesn't fully answer the question, but it doesn't undo my assumption either.
Quote:
Distilling the above results, the four-stroke Ryobi leaf blower kicked out 6.8 times more NOx, 13.5 times more CO and more than 36 times more NMHC than the Raptor.
The two-stroke leaf blower was worse still, generating 23 times the CO and nearly 300 times more NMHC than the crew cab pickup. Let's put that in perspective. To equal the hydrocarbon emissions of about a half-hour of yard work with this two-stroke leaf blower, you'd have to drive a Raptor for 3,887 miles, or the distance from Northern Texas to Anchorage, Alaska.
Now, a leaf blower isn't the same as a lawnmower, but lawnmowers tend to be larger engines, so, maybe they pollute more? Dunno. And something I didn't see mentioned in the article was evaporative emissions. Cars emit very low evaporative emissions. Just sitting there OPE can be "outgassing".
Lastly, the article does briefly mention carbon dioxide, but just for the record, CO2 tracks fuel burn. So we all know how that works (burn more gas, make more CO2, nothing astounding there).
