July 14, 2024
Readers dispute the math, but not the impact of idling engines on environment

Q: A gallon of gas burned puts over 26 pounds of carbon dioxide into the atmosphere, not 20, as a reader stated earlier this week. I think all high school chemistry teachers should have students make this calculation.

All you need is the formula for gas (C8H16), its density (73% that of water), first chemical principles involving molecular weight, and liter-gallon conversion.

John Antoun

A: Yours was one of several responses I got on that.

Q: Mr. Ortendahl claimed that burning a gallon of gasoline released 20 pounds of carbon into the atmosphere. Instead, it’s 20 pounds of carbon dioxide released.

I am whole-heartedly in favor of his point about better light timing. Any engine idling creates unnecessary pollution.

Luther Abel, Alameda

A: And…

Q: There are 5.5 pounds of carbon in a gallon of gas. After combustion, 20 pounds of carbon dioxide are emitted. Smarter lights would still make a huge difference. Why are we not seeing them? The technology has been around for a long time and is getting better.

Niall MacDonagh, Antioch

A: And…

Q: Mr. Orthendahl is correct to say that 1 gallon of gasoline could produce up to 20 pounds of carbon dioxide (CO2) gas when the carbon combines with oxygen.

This doesn’t take away the merits of his suggestion that smart traffic lights would save fuel and time.

Sandra Adams

A: The answers from those correcting the calculation varied from 20-26+ lb. of carbon dioxide and 5.5-7 lb. of carbon per gallon of gas burned. His overall point, though, was not challenged, that a lot of carbon dioxide and carbon spew into the air with each gallon of gas burned, and idling causes a lot of it.

Q: When I lived in a small Connecticut town 60 years ago, we had one traffic light. If it was red when you approached and if nothing was coming the other way, it changed to green.

Related Articles

Transportation |


Readers share questions and stories about self-driving cars: Roadshow

Transportation |


Could ‘smart’ stoplights cut fuel waste and carbon emissions? Roadshow reader runs numbers

Transportation |


Solving the puzzle of a ‘forever’ FasTrak credit: Roadshow

Transportation |


Do I really have to wait at red lights if no one else is around?: Roadshow

Transportation |


Autobahn habit costly lesson for visiting engineer, but it could have been worse: Roadshow

In San Jose, I’ve sat at lights with nothing coming from any direction, but still I sat. Why can’t our talented engineers remedy the situation?

Doris Livezey, San Jose

A: Hopefully, remedies arrive sooner than later.

Q: As a loyal Californian, I am looking into getting an EV. How much does it cost to charge at a public charging station? I checked a number of public charging stations and none post their prices. I guess you have to plug your credit card in, charge the car, and then maybe they’ll let you know how much it cost. Gas stations have to post prices to the tenth of a cent, while EV public charging stations don’t have to post prices at all?

Lou Thompson, Palo Alto

A: Advice for Lou about checking prices before you charge?

Look for Gary Richards at Facebook.com/mr.roadshow or contact him at [email protected].

>