VW's New Plant So Green, It's White

Every auto maker likes to tout the environmental friendliness of its new plants, but leave it to Volkswagen Group of America to brag that the lights for its parking lot not only are energy efficient, but less “irritating” to bugs.

“You should know Volkswagen loves beetles,” quips spokesman Guenther Scherelis.

But behind the jokes is a massive effort to minimize the impact the auto maker's new $1 billion assembly plant has on the air, water and surrounding environment 12 miles (19 km) northeast of downtown Chattanooga, TN.

The Tennessee plant is the auto maker's first in the U.S. since it closed its ill-fated Westmoreland, PA, factory in 1988. It is scheduled to produce a new, as yet unnamed, midsize sedan starting early next year, with annual production initially pegged at 150,000 units.

Frank Fischer, CEO of Chattanooga Operations, says “everything is on track.” Construction is more than 90% complete, and pilot production of the new car has begun.

But in an era when the public increasingly is suspicious of large corporations, auto makers know if they want to market their vehicles as being green, the factories that build them have to be green, too.

And in fact, the new Chattanooga plant is so green, it's white.

The huge parking area has a light-colored concrete surface, instead of black asphalt, and the building roof has a special white-plastic covering. The light coloring is aimed at reducing what the Environmental Protection Agency calls the heat-island effect.

Heat islands are large built-up areas that absorb and retain heat at a higher rate than surrounding rural areas. They can be up to 22° F (12° C) hotter than adjacent properties.

Heat islands can affect communities by increasing summertime peak energy demand, air-conditioning costs, air pollution and greenhouse-gas emissions; heat-related illness and mortality; and water quality, the EPA says.

The Chattanooga facility certainly is big enough to have a thermal impact on the neighborhood. The roof of the paint shop, alone, is 382,000 sq.-ft. (35,489 sq.-m), the equivalent of seven football fields.

Chrysler Group LLC's Pentastar V-6 plant in Trenton, MI, is another new plant that employs a white roof.

The Chrysler facility is the first engine plant to earn a Leadership in Energy and Environmental Design (LEED) Gold certification from the U.S. Green Building Council, which bases its award on site planning, water management, energy use, material use and indoor environmental quality.

Dieter Schleifer, manager-plant infrastructure, says VW is pursuing high-level LEED certification for Chattanooga as well. LEED certification is becoming akin to winning an Oscar in the architectural world.

But in terms of curbing the Chattanooga plant's carbon footprint, he points first to the building's 6-in. (15-cm) thick walls filled with mineral rock wool insulation.

The wall panels emit no volatile organic compounds or chlorofluorocarbons and are 100% recyclable. But most importantly, Schleifer says the super-insulated walls will reduce the plant's energy consumption 35% compared with standard U.S. industrial buildings.

Chattanooga's paint shop also is breaking ground in two areas: priming and eliminating paint sludge.

The actual vehicle-painting process no longer requires a priming step. The primer now is integrated into the base coat. The elimination of one coating process in the paint shop is a major manufacturing innovation that will reduce carbon dioxide emissions 20% and produce less waste, Schleifer says.

Another new technology in Tennessee is dry paint separation. So-called water curtains typically are used to remove overspray and excess paint droplets suspended in the air of paint booths. But VW is introducing a dry concept that uses limestone on the surface of a special filter that collects paint particles from the air without using water.

Eliminating water means the plant will not have to deal with cleaning the wastewater afterwards and disposal of the paint residue, which is known as paint sludge and considered hazardous waste.

The paint-laced limestone waste from the new process is 100% recyclable and used in the production of cement. The dry paint separation process along with some other technologies will reduce energy consumption during painting 30% compared with conventional processes, Schleifer says.

Volkswagen considered numerous other ideas to maximize the environmental friendliness of the facility. Several strategies for using solar power were investigated but ultimately found not to be cost effective.

However, using methane gas from nearby landfills to partially meet energy needs still is being considered for the future, Schleifer says.

Last year, BMW Mfg. Co. LLC in Spartanburg, SC, spent $12 million on a project to use waste methane gas produced at a landfill 10 miles (16 km) away to power two new high-efficiency gas turbine generators that supply 30% of the facility's electrical needs.

In Chattanooga, a so-called living roof that incorporates soil and grass to cool the building and control water runoff may be added later for part of the plant, Schleifer says.

VW also has done a lot with water management. It has created drainage creeks around the property that allow the facility to collect and filter storm water. The water is stored in a cooling pond and will be used in various industrial process and such things as flushing toilets. The move will save hundreds of thousands of gallons of fresh water over the course of a year.

And, like other auto plants, VW has done much to optimize electricity use, from powering every machine, conveyor and robot with the most-efficient electric motors available to using ultra-efficient diode disc lasers that are seven times more efficient than conventional lasers for welding body seams.

Inside, energy saving T5 fluorescent lights reduce energy use 20%, compared with conventional lights. Combined with motion detectors that automatically shut off lights in unused areas, the system is expected to save 1.15 million kW/h annually, enough electricity to supply nearly 280 typical households.

Outside, sodium vapor lights with special mirror technology light the parking lot and provide the same degree of illumination as conventional lighting, but with half the energy consumption.

Schleifer does not go into the entomological details of exactly how the lights interact with insects, but part of the reason is the mirrors focus the light downward, and this somehow creates fewer problems with bugs and flies.

The only bugs most VW employees want to see have four wheels.