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Contents tagged with emissions

  • Restart Your Engines!


    Tags: emissions, epa, driving, cars

    Created: 6/17/2015      Updated: 8/1/2016

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    A Great crested grebe near the Helsinki Museum of Natural History at about 11 pm

    A Great crested grebe near the Helsinki Museum of Natural History at about 11 pm

    I recently returned from presenting some of our Project Squirrel data to the International Colloquium on Arboreal Squirrels. This time, the meeting was held in Finland. Although the meetings filled the day, I spent a lot of time outside too because, this time of year at least, the sun doesn’t set for long in the northern latitudes. On my first night there, between 10pm and midnight, I was able to find nearly 20 species including wagtail, oystercatcher, and even a goshawk being mobbed by dozens of fieldfares and hooded crows. Along with the birds, I noticed something that seemed odd to me—there was no noise coming from stopped cars at red lights. 

    A Barnacle goose

    Barnacle geese are relatives of Canada geese

    At first I thought locals must really be into hybrid cars but upon closer inspection I couldn’t find a single vehicle identified as a hybrid (and because of the danger they can be to rescue workers after a crash, hybrids are usually required to be labeled as such). In fact, amongst the mix of the usual commuter autos, I saw lots of patently non-hybrid and non-quiet vehicles like big American pickups, bigger Audi busses, and even a giant Avtospetsoborudovanie Silant rescue machine (I’m not sure what Silant means in Russian but it can’t be a synonym for “quiet”). Yet these were quiet at intersections too.

    So what gives? It turns out that everyone was simply turning off their vehicles when they stopped at a light to prevent idling. Now I know that idling is bad but where’s the sane line between pausing in your forward motion and idling? I felt a little silly that I didn’t know the answer but as I asked around to various eco-conscious friends, none of them knew the answer either (hence this blog post because I assume lots of people don’t know the answer.)

    Remember back in the 80s and 90s when schools would leave their lights on 24/7 “because it takes more energy to turn on the lights than it does to keep the running overnight”? Cars were like that too.  Carburetors and chokes used a ton of gas to get the car started then required a good 15 minutes or more to warm up to operating temperatures. On the other hand, modern fuel injected, computer controlled engines are ready to drive as soon as you start them (even in cold weather, as long as you don’t stomp on the gas pedal but stomping on the gas pedal is bad for different reasons under all conditions) and the amount of gas you burn when starting is about equal to the amount you burn during 10 seconds of idling. That said, restarting your car causes wear on the battery, starter, and other parts. Most of the references I found suggested the cost of gas begins to exceed the increased maintenance costs after a mere 30 to 60 seconds of idling.

    My conclusion from all this is: turn the car off as often as possible. Now I don’t think that turning your car off every time you come to a stop is a safe thing to do, at least in American traffic. In fact, it’s usually illegal here and, at least as far as I can determine in the English language translations, Finnish law doesn’t require it either. Some countries apparently do require turning off the car at intersections under certain circumstances and many countries have laws that prohibit more than 1 minute of idling per hour. However, I am convinced that idling the car as I wait for the kids to get in or for the cabin to warm is costing me money that I don’t need to spend, not to mention creating tons of excess CO2. I have also begun paying more attention to what I do at the beginning and end of every trip; I’m careful to turn the car on only after I’m done fiddling with my phone, jacket, glasses or whatever, and turn it off as soon as I park. 

    This really was something I should have known since study on the topic was active in the late 80s. I didn’t find a lot of news reporting on it until the early 2000s which is reasonable since it took until then for the knowledge to be applicable to most drivers. In researching this topic, I found a lot of reporting online but links from the articles to official sources and governmental reviews were broken more than usual. There are, of course, a lot of academic papers on this but most are behind paywalls, though you can still get a lot out of the abstracts. This one about motorcycles highlights some of the consumer issues.

    That said, this Canadian site gives a great summary and the EPA has lot of detailed tables that could let you do some interesting calculations for your own vehicle.

    Though it seems most of the EPA site is devoted to understanding what you can buy and how to shop, if you read between the lines, they also say, idling less makes a measurable difference.

    Steve Sullivan, Senior Curator of Urban Ecology

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