In January 2012, the U.S. Pacific Northwest National Laboratory (PNNL) commenced a project to design low-cost efficient manufacturing of pressurized conformal compressed natural gas (CNG) storage tanks for natural gas vehicles (NGVs). Last month, at the 2013 Energy Innovation Summit of high-impact energy research funded by the U.S. DOE’s Advanced Research Projects Agency-Energy, or ARPA-E, PNNL exhibited its work.
Specifically, project objectives are to:
- Develop and demonstrate a new concept for conformal compressed natural gas (CNG) storage tanks
- Reduce the overall material and manufacturing costs
- Achieve volumetric efficiencies that exceed 90% of the rectangular envelope
- Achieve volumetric energy density that exceeds 9.2 MJ/L
PNNL engineer Kevin Simmons and his team are developing a special, lightweight fuel tanks that make better use of the limited space in vehicles. PNNL’s conformable natural gas tank would represent a dramatic improvement in conformability and a reduction in weight and cost over current storage options. The fuel tank design uses a unique method of production called superplastic forming. The method involves welding sheet metal in certain places and blowing air between the sheets to expand them, forming the inner chamber, like an air mattress.
Advanced Metal Storage will fit more vehicle space than traditional cylindrical tanks. It also helps the car weigh less, which makes them more efficient. A PNNL tank is expected to cost $1,500 to make and pack 12 MJ of energy per kilogram, about twice the energy density of the metal in compressed natural gas tanks.
The project is funded through ARPA-E, within the U.S. Department of Energy’s MOVE (Methane Opportunities for Vehicular Energy) program.
Lincoln Composites is a partner in the project.