NORTHBROOK, IL —The Sierra Club, America’s oldest and largest grassroots environmental organization, has partnered with the Donlen, North America’s fastest growing vehicle fleet management company, in a strategic alliance to enable commercial and municipal vehicle fleets to monitor and reduce their carbon emissions.

“Donlen’s Carbon CalculatorTM tool, which we tailored for this program, successfully provides a full picture of carbon costs and economics for the vehicle fleet community,” said Gary Rappeport, CEO of Donlen, based in Northbrook, Illinois. “Fleet managers cannot make effective decisions in a vacuum. Simply looking at isolated carbon data will not provide the complete picture. With this calculator, carbon-conscious decision makers can now reach a conclusion that is well-received by an organization’s environmental and finance teams, just as our existing clients also use this resource.”

Available at, the tool allows vehicle fleet managers to accurately determine and compare global warming and air pollution emissions, as well as fuel and maintenance costs for all types of vehicles. For example, the tool calculates that a hybrid vehicle can cost 22% less to operate, and emits 46% less global warming pollution over a three-year period, than the average mid-size sedan. In addition, the tool provides a financial analysis of carbon output and how it affects the organization’s bottom line.

“Donlen’s online tool will encourage local governments and private businesses to transform their vehicle fleets into greenfleets,” said Glen Brand, Director of the Sierra Club’s Cool Cities campaign, which works to get cities across the country to implement clean energy solutions such as energy efficiency, cleaner vehicles and renewable power ( “Greenfleets are an important and practical strategy to reducing energy costs, global warming pollution, and our country’s dependence on fossil fuels,” added Brand.

Donlen (, has offices nationwide, and is North America’s fastest growing provider of innovative fleet management programs. Since its inception in 1965, Donlen has combined industry-leading innovative technology, proactive and responsive customer service, and highly experienced industry experts.

About Donlen
Donlen, with headquarters in Northbrook, IL, and offices nationwide, is a global provider of innovative fleet management programs. Since 1965, Donlen has offered its clients highly personalized and responsive customer service. Donlen has been recognized as one of The 101 Best and Brightest Places to Work For in Chicago, and as an industry leader by the International Association of Outsourcing Professionals (IAOP) in its Global Outsourcing 100 Award from 2006-2008. For more information about Donlen, visit .