NIST Calculates High Cost of Hydrogen Pipelines, Shows How to Reduce It

[OKIsItJustMe]

http://www.nist.gov/mml/acmd/201507_h2_pipeline.cfm

[font face=Serif][font size=5]NIST Calculates High Cost of Hydrogen Pipelines, Shows How to Reduce It[/font]
From NIST Tech Beat: July 20, 2015

Contact: Laura Ost
303-497-4880

[font size=3]The National Institute of Standards and Technology (NIST) has put firm numbers on the high costs of installing pipelines to transport hydrogen fuel—and also found a way to reduce those costs.

Pipelines to carry hydrogen cost more than other gas pipelines because of the measures required to combat the damage hydrogen does to steel’s mechanical properties over time. NIST researchers calculated that hydrogen-specific steel pipelines can cost as much as 68 percent more than natural gas pipelines, depending on pipe diameter and operating pressure.* By contrast, a widely used cost model** suggests a cost penalty of only about 10 percent.

But the good news, according to the new NIST study, is that hydrogen transport costs could be reduced for most pipeline sizes and pressures by modifying industry codes*** to allow the use of a higher-strength grade of steel alloy without requiring thicker pipe walls. The stronger steel is more expensive, but dropping the requirement for thicker walls would reduce materials use and related welding and labor costs, resulting in a net cost reduction. The code modifications, which NIST has proposed to the American Society of Mechanical Engineers (ASME), would not lower pipeline performance or safety, the NIST authors say.

"The cost savings comes from using less—because of thinner walls—of the more expensive material," says NIST materials scientist James Fekete, a co-author of the study. "The current code does not allow you to reduce thickness when using higher-strength material, so costs would increase. With the proposed code, in most cases, you can get a net savings with a thinner pipe wall, because the net reduction in material exceeds the higher cost per unit weight."

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[happyslug]

1. And the lost of Hydrogen right through the metal is what?

Hydrogen is the SMALLEST ATOM. In its liquid form, it leaks through steel at a rate of about 1% per day. This is NOT at any joint or weld, this is right through the steel for in its liquid form, the Hydrogen is smaller then the gap between the Iron atoms in a steel pipe.

Now, in its gaseous form Hydrogen loss through steel drops severely, but still occurs.

http://www.technifab.com/cryogenic-resource-library/about-liquid-hydrogen.html

The density of liquid hydrogen is 0.070 kg/L, compared to 0.030 kg/L for 10,000-psi gas tanks.

http://www.fsec.ucf.edu/en/consumer/hydrogen/basics/storage-liquid.htm

Density of gas at 1 atmosphere and 20 degrees Celsius:

Hydrogen: 83.764 g/mi
Methane: 651.19 g/ml
gasoline: 4400 g/mi

http://www.fsec.ucf.edu/en/publications/pdf/FSEC-CR-204-88-LiquidH2.pdf

Thus you will see a substantial loss right through the walls if you use Liquid hydrogen, but that loss drops substantively if you go with Gaseous hydrogen. The problem is Gaseous Hydrogen takes up a lot more space then any other fuel, over 50 times the space as gasoline for example (Gasoline is in a liquid form at 20 degree Celsius).

This report accepts that Hydrogen will have to be shipped as a gas not a liquid which means a huge pipe line system, much larger then Natural Gas (Methane). The difference in size will be a factor of 10, through that can be reduced by Hydrogen's greater ability to provide energy (1/3 more energy per volume of gas). This problem is ignored in the report, the report just being on how to build a gaseous hydrogen pipeline system not how large it has to be to replace the present system to transport gasoline.

[OKIsItJustMe]

2. Perhaps I am naive

I believe NIST is familiar with the characteristics of hydrogen.