Ultra-Light Conformable Natural Gas Tank
Pacific Northwest National Laboratory (PNNL)
Low-Cost Efficient Manufacturing of Pressurized Conformal Compressed Natural Gas Storage Tanks
10/01/2012 to 09/30/2014
Today's natural gas vehicles are fitted with on-board fuel tanks that are too large, cumbersome, and expensive to properly facilitate the widespread adoption of natural gas vehicles in the U.S. and globally. Additionally, the low volumetric density of natural gas--roughly 30% less energy by volume than gasoline--limits the driving range of natural gas vehicles and makes cost-effective storage solutions a significant challenge. Dramatic improvements must be made to the capacity, conformability, and cost of on-board storage to accelerate natural gas vehicle adoption.
Project Innovation + Advantages:
PNNL is developing a low-cost, conformable natural gas tank for light-duty vehicles utilizing the same metal forming techniques used to fabricate high-strength cruise missile fins. Traditional gas tanks are made using a method known as arc welding, where an electric arc is used to melt and combine metals, which can limit their conformability. PNNL's ultra-light design relies on friction stir welding, where metal is softened--like taffy--instead of melted, which allows the metal to retain its original properties and preserves its conformability. The manufacturing process for PNNL's tanks incorporates high-strength internal strut technology that efficiently fits into a vehicle, offering a tank that costs around $1500, a substantial price reduction compared to today's best tanks.
If successful, PNNL's ultra-light, conformable natural gas tank would represent a dramatic improvement in conformability and a reduction in weight and cost over current storage options.
Improving the convenience of natural gas vehicle ownership could reduce our dependence on foreign oil and make consumers less vulnerable to sudden oil price shocks.
Compressed natural gas currently costs half as much per gallon of gasoline equivalent. With the average American spending over $2000 per year on gas, enabling the use of natural gas vehicles could save drivers $1000 per year.
Natural gas vehicles produce approximately 10% less greenhouse gas emissions than gasoline-powered vehicles throughout the fuel life cycle.