The infrastructure and technology exists today to begin using hydrogen as a fuel. This will involve the proliferation of onsite hydrogen production using electrolysis or reformation from natural gas as well as neighborhood stations.
We have a sprawling, million mile natural gas pipeline network but only seven hundred miles of hydrogen pipeline, primarily serving high volume users such as Gulf Coast region refineries. In addition to the short pipelines serving high volume users, we ship tanks of hydrogen in either compressed or liquefied form. This is acceptable if you need hydrogen for some chemical manufacturing process, but it's a poor way to transport energy. The liquefaction process alone eats up 30% of the energy value of any hydrogen transported in this fashion.
But thanks to recent innovations, that hydrogen pipeline network could spread.
Early attempts to integrate hydrogen into existing pipelines tests supplementing natural gas with up to 20% hydrogen. This worked well for combustion but not for transport. Pipeline welds that easily stopped the larger natural gas molecules were quite willing to let hydrogen slip through, resulting in losses and the potential for fires and explosions where the gas accumulated.
Plastics and metals had long been used for piping, but plastics are permeable to hydrogen and metals are subject to hydrogen embrittlement as well as being permeable. Hydrogen molecules are a pair of atoms, and they pass through plastics still joined together. When presented with a metal barrier, the hydrogen atoms must dissociate, pass through the metal as individual atoms, and then find a partner again on the other side of the barrier.
Where others saw a problem, Greg Blencoe of Hydrogen Discoveries saw opportunity. Laminating layers of plastic and metal produced a result much tighter than any single pipeline material. The challenge is to find the right materials. The best structural metals in terms of resistance to hydrogen embrittlement are copper, aluminum, and stainless steel. Copper and stainless steel are relatively expensive and function well in some applications, while inexpensive, durable aluminum would make up the bulk of the metal in any long distance pipeline. The best plastic is high density polyethylene, one of the most common plastics made today.
Even with the sandwich of different materials, some of the hydrogen will still escape--both directly through the pipeline and, in particular, at the joints. Some scheme must be implemented to collect and reintroduce the gas or consume it. Various methods involving either an air or water jacket around the pipeline are effective depending on the volume of hydrogen carried and the distance it must traverse.
Limiting the number of joints in the line is another means of reducing leakage. Fiberspar's spools of laminated pipe or Smart Pipe Company's mobile fabrication are a means to achieve this goal. Smart Pipe's claim to fame is the ability to run their product through existing pipelines for distances of up to ten miles. A very large portion of pipeline installation cost, perhaps as much as 90 percent, comes from digging and installation, so this process could make the conversion of existing natural gas lines to hydrogen an attractive option.
Given the relative complexity of this style of pipeline it will be used at first as a replacement material in existing oil refineries. Between that event and the far horizon of a large scale national hydrogen pipeline network, the incremental step seems obvious: the hydrogen used in Louisiana's refinery row could be made using wind energy from the Texas plains and then piped to where it is needed.
We have a sprawling, million mile natural gas pipeline network but only seven hundred miles of hydrogen pipeline, primarily serving high volume users such as Gulf Coast region refineries. In addition to the short pipelines serving high volume users, we ship tanks of hydrogen in either compressed or liquefied form. This is acceptable if you need hydrogen for some chemical manufacturing process, but it's a poor way to transport energy. The liquefaction process alone eats up 30% of the energy value of any hydrogen transported in this fashion.
But thanks to recent innovations, that hydrogen pipeline network could spread.
Early attempts to integrate hydrogen into existing pipelines tests supplementing natural gas with up to 20% hydrogen. This worked well for combustion but not for transport. Pipeline welds that easily stopped the larger natural gas molecules were quite willing to let hydrogen slip through, resulting in losses and the potential for fires and explosions where the gas accumulated.
Plastics and metals had long been used for piping, but plastics are permeable to hydrogen and metals are subject to hydrogen embrittlement as well as being permeable. Hydrogen molecules are a pair of atoms, and they pass through plastics still joined together. When presented with a metal barrier, the hydrogen atoms must dissociate, pass through the metal as individual atoms, and then find a partner again on the other side of the barrier.
Where others saw a problem, Greg Blencoe of Hydrogen Discoveries saw opportunity. Laminating layers of plastic and metal produced a result much tighter than any single pipeline material. The challenge is to find the right materials. The best structural metals in terms of resistance to hydrogen embrittlement are copper, aluminum, and stainless steel. Copper and stainless steel are relatively expensive and function well in some applications, while inexpensive, durable aluminum would make up the bulk of the metal in any long distance pipeline. The best plastic is high density polyethylene, one of the most common plastics made today.
Even with the sandwich of different materials, some of the hydrogen will still escape--both directly through the pipeline and, in particular, at the joints. Some scheme must be implemented to collect and reintroduce the gas or consume it. Various methods involving either an air or water jacket around the pipeline are effective depending on the volume of hydrogen carried and the distance it must traverse.
Limiting the number of joints in the line is another means of reducing leakage. Fiberspar's spools of laminated pipe or Smart Pipe Company's mobile fabrication are a means to achieve this goal. Smart Pipe's claim to fame is the ability to run their product through existing pipelines for distances of up to ten miles. A very large portion of pipeline installation cost, perhaps as much as 90 percent, comes from digging and installation, so this process could make the conversion of existing natural gas lines to hydrogen an attractive option.
Given the relative complexity of this style of pipeline it will be used at first as a replacement material in existing oil refineries. Between that event and the far horizon of a large scale national hydrogen pipeline network, the incremental step seems obvious: the hydrogen used in Louisiana's refinery row could be made using wind energy from the Texas plains and then piped to where it is needed.
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