Hydrogen has held the interest of scientists as a source of energy since the 1800s due to its abundance in the environment and high energy per unit mass. Most of the hydrogen in nature exists as water or bonded in organic compounds, however, and its high vapor pressure means significant compression is required to take advantage of the energy density. Hydrogen also has additional infrastructure challenges associated with its small molecular size and negative effects on material fatigue resistance. While the application of hydrogen as an energy source results in zero emissions, the production of hydrogen primarily relies on steam methane reforming which is energy intensive and releases carbon dioxide (CO2) to the atmosphere.
To address these challenges, the Department of Energy (DOE) and NETL are currently researching hydrogen production, delivery, and storage, with ongoing activities in fuel cell development, manufacturing, systems analysis and integration, safety, standards, and education. DOE/NETL’s Natural Gas Infrastructure Program will explore a mix of laboratory and field-based research focused on:
- Next-Generation Material Development: Depending on the concentration and the type of material to which it has prolonged exposure, hydrogen can degrade the fatigue and fracture resistance of structural components. Known as hydrogen embrittlement, this degradation affects all aspects of storage and distribution, including pipelines and compressors. This represents a key challenge for novel material design that can provide long-term reliably to infrastructure, whether through retrofits of existing gas pipelines or development of new transmission lines.
- Natural Gas Decarbonization: Hydrogen produced by the electrochemical splitting of water using renewable electricity has seen some decline in baseload cost of production but is still significantly more expensive than hydrogen produced from steam methane reforming of natural gas, even when the cost of capturing and storing CO2 is included. However, reforming with capture and storage is still significantly more expensive than current reforming operations without capture and storage and only limited pipeline infrastructure exists to transport CO2 to suitable geological storage sites within the U.S.
An alternative interest to DOE is the direct conversion of methane into solid carbon and hydrogen gas. Preliminary analyses indicate that such a process can be more efficient and potentially less expensive than steam methane reforming with CO2 capture and storage. Solid carbon can be easily transported by truck or rail to an appropriate storage, and, depending on the morphology of the carbon produced (e.g., amorphous carbon, activated carbon and carbon fibers), it may be sold for beneficial applications. NETL is currently managing four research and development projects for converting natural gas into solid carbon products. These technologies are being examined for the mitigation of flare natural gas but could also be applicable to natural gas decarbonization.
- Advanced Transport and Storage Monitoring and Data Analysis: The small molecular structure of hydrogen presents challenges related to gas permeability, mechanical compression efficiency, and high-density storage. Thus, advanced systems to monitor potential issues related to the integrity of both the transportation and storage infrastructure represents an impactful research area of sensor development, data collection, and analytics. Incorporation of the data to develop new algorithms can promote mitigation methods that enable reliable and safe widespread hydrogen transmission.
Hydrogen Strategy: Enabling a Low-Carbon Economy (July 2020)