Henderson Dennis K, Koenig Brett E, Mokhtarian Patricia L
a University of California , Davis , California.
J Air Waste Manag Assoc. 1996 Jan;46(1):47-57. doi: 10.1080/10473289.1996.10467440.
Transportation control measures are often implemented for their environmental benefits, but there is a need to quantify what benefits actually occur. Telecommuting has the potential to reduce the number of daily trips and miles traveled with personal vehicles and, consequently, the overall emissions resulting from vehicle activity. This search studies the emissions impacts of telecommuting for the participants of the Puget Sound Telecommuting Demonstration Project (PSTDP). The California Air Resources Board's emissions models, EMFAC7F and BURDEN7F, are used to estimate the emissions on telecommuting days and non-telecommuting days, based on travel diaries completed by program participants. This study, among the first of its kind, represents the most sophisticated application of emissions models to travel diary data. Analysis of the travel diary data and the emissions model output supports the hypothesis that telecommuting has beneficial transportation and air quality impacts. The most important results are that telecommuting decreases the number of daily trips (by 30%), the vehicle-miles traveled (VMT) (by 63%), and the number of cold starts (by 44%), especially those taking place in early morning. These reductions are shown to have a large effect on daily emissions, with a 50% to 60% decrease in pollutants generated by a telecommuter's personal vehicle use on a telecommuting day. These net savings are almost entirely due to the elimination of commute trips, as non-commute trips increased by 0.33 trips per person-day (9% of the total trips), and the non-commute VMT increased by 2.2 miles. Overall reduc- tions in travel and emissions of this magnitude are observed because the telecommuters in this sample are long-distance commuters, with commutes twice as long as the regional average. However, even as telecommuting adoption moves into the mainstream, its net impacts are still expected to be beneficial- a reduction in VMT and in emissions. It is important to note that when the level of telecommuting is considered (that is, the percentage of work days that employees actually telecommute), the weekly savings are a much smaller proportion of total weekday travel. Also, these findings represent average per-capita reductions; the aggregate (or overall, regionwide) impacts are determined by scaling these reductions by the number of program participants. Thus, the aggregate effectiveness of telecommuting must take into account the number of people likely to participate as telecommuters and how often they telecommute, not just the per-capita, peroccasion impacts.
交通控制措施的实施往往是出于其环境效益，但有必要对实际产生的效益进行量化。远程办公有可能减少每日出行次数和私人车辆行驶里程，从而减少车辆活动产生的总体排放。本研究探讨了普吉特海湾远程办公示范项目（PSTDP）参与者远程办公对排放的影响。基于项目参与者填写的出行日记，使用加利福尼亚空气资源委员会的排放模型EMFAC7F和BURDEN7F来估算远程办公日和非远程办公日的排放量。本研究是同类研究中的首例，代表了排放模型在出行日记数据方面最复杂的应用。对出行日记数据和排放模型输出的分析支持了远程办公对交通和空气质量有有益影响这一假设。最重要的结果是，远程办公减少了每日出行次数（减少30%）、车辆行驶里程（VMT）（减少63%）以及冷启动次数（减少44%），尤其是清晨的冷启动次数。这些减少对每日排放有很大影响，远程办公日远程办公者私人车辆使用产生的污染物减少了50%至60%。这些净节省几乎完全归因于通勤出行的消除，因为非通勤出行每人每天增加了0.33次出行（占总出行次数的9%），非通勤VMT增加了2.2英里。观察到如此大幅度的出行和排放总体减少，是因为该样本中的远程办公者是长途通勤者，通勤距离是地区平均水平的两倍。然而，即使远程办公的采用进入主流，其净影响预计仍将是有益的——VMT和排放的减少。需要注意的是，当考虑远程办公的水平（即员工实际远程办公的工作日百分比）时，每周节省的出行量在工作日总出行量中所占比例要小得多。此外，这些发现代表的是人均减少量；总体（或整个地区范围）的影响是通过将这些减少量按项目参与者数量进行缩放来确定的。因此，远程办公的总体有效性必须考虑到可能成为远程办公者的人数以及他们远程办公的频率，而不仅仅是人均每次的影响。
