Federal investment has created an unprecedented opportunity for the private sector to partner with federal agencies to jumpstart the hydrogen economy. The United States Department of Energy’s (DOE) Bipartisan Infrastructure Law includes $9.5 billion dollars in clean hydrogen incentives with the intention of establishing several regional clean hydrogen hubs. This will further strengthen energy security and decarbonize many sectors as we transition to clean energy.
Hydrogen is a versatile energy carrier and its applications today range across a number of industries such as oil refining, ammonia and steel production. This allows us to leverage existing assets and infrastructure to scale up the hydrogen economy by combining a range of new technologies enabling the basis for regional hydrogen hubs. While the most recent focus in establishing these hubs has rightly been on developing solutions for the individual assets within a hub, the backbone of hydrogen hubs will be the control systems that link the individual assets together. This means that systems integration will play a key role in the success of these projects.
The anatomy of a hydrogen hub can be divided into four segments: hydrogen production (making it), hydrogen storage and hydrogen transportation (moving it), and electrical power generation (using it).
Each of these segments can then be divided further. Hydrogen production, for example, will occur through a variety of different processes from many different producers. Production methods will range from existing fossil fuel facilities using steam methane reforming that will likely be modernized by adding carbon capture units, to new electrolyzer and biomass facilities. Hydrogen that is produced across these processes will then need to be transported to either storage facilities or electrical power generation units. These different pieces will need to be monitored effectively and controlled efficiently to ensure a robust hydrogen network.
Because hub establishment will require multiple partners across the energy industry, the control systems within each hub will have a different range of systems from many vendors, as well as a wide range of functionalities and communication protocols. It will therefore be necessary to establish some form of a supervisory control system to integrate all the individual controls into one centralized system to get an accurate view of what is happening across the entire hub at any given time.
Let's take a look at the control systems architecture needed for the hydrogen hub establishment.
Integrated (SCADA and distributed / embedded) controls
To design a seamless operating system, a control systems integration plan needs to be developed in the early hub planning stages and not an afterthought. The systems integrator or integrators must take existing network architecture into consideration, as well as plan adequately for future expansion because hub development will roll out in stages and continue to expand.
In order to get an accurate depiction of what is happening across an entire hydrogen hub, the control system should supervise electrolyzers and other hydrogen generation units, monitor pipeline activity, control electrochemical fuel cell interface with the power grid, and interface with safety instrumented systems (SIS). This means data from PLCs, DCS and SIS systems will all converge to a central location with the help of remote/SCADA systems. Advanced applications will need to be evaluated for integration between hydrogen hubs and both the electric grid and natural gas grid, to manage grid balance.
As hydrogen can be highly volatile, safety system implementation is a crucial piece of hub integration. Because hydrogen usage is well established across industries, regulations, guidelines, and codes and standards already exist to facilitate safety guidelines around the industrial use of hydrogen. In addition to existing regulations, systems have already been put in place to establish codes and standards that facilitate hydrogen and fuel cell commercialization. Layer of protection analysis (IEC 61511/ISA84) will continue to govern safety integrity level (SIL) implementation for safety instrumented systems (SIS). The hydrogen hub centralized control room will be required to interface with safety systems to facilitate remote shutdowns as well as take necessary control action during abnormal events.
Human-machine interface (HMI), alarms and production, demand analytics
Control room operators will need visibility into the entire hydrogen hub without loading unnecessary data onto graphics. The HMI should be structured so that operators are quickly alerted to abnormal conditions and can take immediate action to rectify any issues. High performance graphics, following ISA-101 HMI standard should be developed so that operators are presented with useful information rather than being overloaded with data points. Display hierarchy is critical to the development of hydrogen hub HMI because of the vast network of assets that are integrated to a central system. Analysis should be done in advance to determine how to structure this hierarchy as well as how to best integrate future assets as they become connected to the hub.
A robust alarm system will be an important part of the hydrogen hub’s central control system for operators to be quickly alerted to abnormal conditions across the entirety of the hydrogen hub. Alarm rationalisation (as per ANSI/ISA-18.2) will minimize the number of alarm activations and nuisance alarms. Following rationalisation, the alarm system will result in a rapid response from control room operators who learn that the alarm system can be trusted to only report on necessary events, thereby reducing complacency.
Technology advancements in recent years have led to a push for the convergence of IT and OT systems, but it is important to understand the purpose of each system. OT systems prioritize maintaining reliable and safe production operations while IT systems prioritize securing business data. Multiple different private entities will form hydrogen hub networks composed of differing equipment vendors and communication technologies. Careful planning is required so businesses can share vital production data with the entire hub, while protecting their own business networks and ensuring overall system security and integrity in line with Industrial Control Systems (ICS) is based on IEC/ISA 62443. The hydrogen hub in turn will likely require its own independent IT network infrastructure. Early planning of this network architecture allows communication to be streamlined across the networks associated with all involved private entities.
Integral to IT/OT infrastructure planning is cybersecurity. Traditional IT risk assessments do not fully capture process risks at the OT level as highlighted by ANSI/ISA/IEC 62443. This is where new cyber risk assessments as part of CHAZOP (Control Systems HAZOP methodology) is useful. Performing CHAZOP allows us to systematically identify key risks at the OT level that have health, safety and environmental implications. Performing a CHAZOP will help stakeholders and decision-makers identify true risks across the hydrogen hub and take appropriate mitigation measures.
Creating an effective hydrogen ecosystem
Individual pieces of the hydrogen ecosystem can only function together if they are able to operate effectively with one another. Control systems and network planning should be started early in the hub development phase to ensure that communication, data and information are integrated, and streamlined across entities. Defining communication protocols at the hardware purchasing stage, identifying all necessary hardware interfaces upfront is key to the planning process. Alternatively, trying to piece together communication links in the late stages of hub development is both more expensive and time-consuming. Control systems planning in hydrogen hub development should be a priority to systematically design a robust control infrastructure helping make, move and use hydrogen more effectively.