Environmental awareness has become part of the fabric of our society. And while we still have a very long way to go, there's more of an effort than ever to make the products we use and consume more environmentally friendly. Compressors and generators supply much of the power on today's jobsites, so manufacturers' efforts to design and build greener machines go a long way toward ensuring cleaner and greener jobsites.

"Manufacturers are putting a great deal of effort into making equipment more environmentally friendly - and with compressors, that focus is primarily on noise reduction and fuel efficiency," says Chance Chartters, direct accounts manager, Mobilair, Kaeser Compressors.

As most are aware, EPA regulations for diesel engines have gotten much more strict over the past decade and are due to get tighter still in 2008 as Tier III/Tier IV interim regulations go into effect. According to Todd Howe, product marketing manager for generators at Ingersoll Rand, this presents a formidable challenge to manufacturers who aim to build energy-efficient, quiet and compact compressors and generators.

For example, Howe says, new EPA-compliant engines are not usually "drop-in" replacements for their predecessors. Often, the new engines mount differently and require different plumbing and wiring. As a result, the entire product can require a redesign to incorporate the new engine.

With each [EPA] Tier change, the engines run hotter, so the cooling systems in the machines get bigger, the machines themselves get louder and so on. Balancing all the various design objectives keeps engineers very busy, Howe says.