Today, the environmental issues that are driving automakers to increase fuel efficiency, reduce emissions and optimize end-of-life recycling are also affecting the competition between plastic fuel tanks and steel fuel tanks. The impermeable nature of steel facilitates compliance to demanding evaporative emission standards. In fact, all of the gasoline-powered vehicles certified to meet the California Air Resources Board Partial Zero Emission Vehicle (PZEV) standards have steel fuel tanks. In addition, steel tanks are fully recycled, at no cost to the automaker or consumer, using an existing infrastructure. When the environmental benefits of steel fuel tanks are combined with steel's improvements in design flexibility, manufacturability, durability, cost competitiveness, and support services, today's steel tanks offer "performance with environmental responsibility."
Stricter emission regulations, such as those set by California Air Resources Board (CARB) and applied regulations in other states, are making it difficult for plastic tanks, which have permeation problems. The industry has tried a variety of solutions, most of which result in an increase of new plastic materials and additional films for tank walls. While this may reduce the emissions problem for plastic tanks, it is increasing the cost to produce/manufacture plastic tanks. More important, plastic tanks haves a negative environmental impact. Plastic fuel tanks from vehicles that have reached the end of their useful life are discarded to landfills. This is one of the unpublicized environmental ‘issues’ associated with plastic fuel tanks.
Plastic tanks are not recycled because there is no cost-effective recycling infrastructure. As a result, virtually all end up in landfills. Without doubt, plastic fuel tanks reaching the end of their service life have significant negative environmental impact. There are over 250 million vehicles on the road in North America. If 80 percent of the vehicles have plastic tanks when vehicles retire, the plastic tanks placed end-to-end would stretch 125,000 miles, or five times around the world. In Europe, if all plastic tanks were discarded to a single landfill, there would be a mountain of plastic tanks over 370 meters feet high - higher than the Eiffel Tower.
Steel is North America’s number one recycled material. Each year, more steel is recycled than aluminum, paper, glass and plastic combined!
The very roots of the automobile recycling industry lie in the steel industry’s need for ferrous scrap. Once all the fluids have been drained and all the reusable parts have been removed from the car, ferrous scrap processors shred the car – including the fuel tank that has been cleaned and sell the ferrous material to a steel mill. It is a profitable business for recyclers and it is a necessary resource for steel makers. The steel recycling infrastructure is a well established network of more than 2,000 ferrous scrap processors.
Recycling steel saves energy and natural resources. By recycling scrap steel, the steel industry annually saves sufficient energy to power about 18 million households for a year. Recycling one ton of steel conserves 2500 pounds (1136 kg) of iron ore, 1400 pounds (636 kg) of coal and 120 pounds (55 kg) of limestone.
Steel is a unique material because it always contains recycled steel. The basic oxygen furnace (BOF) process uses 25 to 35 percent old steel to make new product, and the electric arc furnace (EAF) process uses virtually 100 percent old steel to make new.
11/8/2013 - SASFT members from Spectra Premium Industries presentation from ITB Automotive Fuel Systems in Shanghai regarding plastic versus steel fuel tanks.
7/10/2012 - A luxury SUV hybrid comes equipped with a 25 gallon sealed, steel fuel tank system that requires structural resistance to high internal pressure.
3/14/2012 - This advanced hybrid electric cross-over vehicle features a sealed steel tank that requires structural resistance to high internal pressure.
The next generation of steels offer the best solution to automakers for lightweighting vehicles - one that does not sacrifice safety or affordability in helping meet the more stringent fuel economy standards.