MTEP15 Chapter 6.3 Gas-Electric Coordination

MTEP15 Chapter 6.3 Gas-Electric Coordination

Over the past several years, MISO has made significant progress on the gas-electric coordination front, enhancing system awareness, furthering coordinating operations, and facilitating cross-industry education and communication. The addition of the PLEXOS Integrated Energy Model to MISO’s planning toolkit represents another step towards better understanding and planning for future gas-electric system interactions.

This chapter provides historical context for and details on current gas-electric initiatives at MISO in the realm of long-term system planning.

The addition of the PLEXOS Integrated Energy Model to MISO’s planning toolkit represents another step towards better understanding and planning for future gas-electric system interactions

Electric and Natural Gas Coordination Task Force

MISO’s gas-electric coordination efforts originated in 2011 with a series of investigations into the ability of natural gas infrastructure to serve growing demand. The findings from these analyses, published in 2012, spurred an ongoing conversation with MISO stakeholders and the natural gas industry. While MISO held preliminary meetings across the footprint to discuss gas-electric interdependency, the Federal Energy Regulatory Commission (FERC) planned its own set of regional discussions on the topic. The takeaways from these forums and the MISO zonal meetings signaled the need for a separate MISO stakeholder body to address gas-electric interdependency. In response, MISO and its stakeholders established the Electric and Natural Gas Coordination Task Force (ENGCTF) in October 2012.

Shortly after its formation, the task force initiated a process of gas-electric issue identification and prioritization. Cross-industry teams formed to draft Issue Summary Papers, intended to guide discussion within the task force and provide recommendations on high priority issues, including:

  • System awareness and coordinated operations with the gas industry
  • Cross-industry communications
  • The misalignment of gas and electric industry market timelines

The ENGCTF also devoted a significant amount of time over the past few years to cross-industry education, increasing understanding between the gas and electric industries of each other’s regulatory, business, operational and planning constructs. The group continues to provide a forum for discussion of key gas-electric topics.

Gas-Electric Coordination and Long-Term System Planning

While many of MISO’s current gas-electric coordination efforts focus on operational or market design issues, some of the earliest aimed to better understand the mid- to long-range impact of regulatory, technological and economic developments on future gas-electric system interactions. Specifically, in late 2011, MISO commissioned EnVision Energy to study historical flows and future capacity availability on natural gas pipelines in the Midwest. The results of these analyses (Phase 1, Phase 2 ,Phase 3) highlighted the potential need for gas infrastructure build-out in the MISO North and Central Regions, in a scenario with increasing demand for gas from electric generators.

The issue of gas infrastructure adequacy was revisited by MISO in 2013. The new analysis featured an expanded study footprint, including the newly integrated South Region, and an enhanced methodology, adding a dynamic pipeline modeling component. Study findings indicated adequate pipeline capacity for the MISO footprint in the near term under a base-demand scenario, with localized exceptions in MISO’s North and Central Regions. These results were attributed to significant and fast-paced developments in the gas industry, including 1) new and increasing supplies from shale gas basins, driving major changes in pipeline flow patterns across the country, and 2) additions to and increasing interconnectivity of natural gas infrastructure. The study report also identified opportunities for future progress on gas-electric coordination, including several recommendations aligned with the goals of the ENGCTF.

In addition to commissioning studies of long-term gas infrastructure adequacy, MISO also engaged in the Eastern Interconnection Planning Collaborative (EIPC) study of the gas-electric interface. This effort spanned several years and encompassed four major targets:

  • Target 1: Baseline assessment of electric-natural gas infrastructure in the study footprint
  • Target 2: Evaluation of the capability of the natural gas systems to meet long-term gas demand
  • Target 3: Evaluation of natural gas system contingencies
  • Target 4: Review of operational/planning issues affecting the availability of dual-fuel generation

 

MISO was one of a group of planning authorities participating in the study, providing guidance on scope and methodology, with input from the ENGCTF.

At a high level, the EIPC study identified few issues of concern with respect to gas-electric interfaces in MISO, resulting from an ample and interconnected pipeline network throughout the footprint, as well as access to numerous gas producing basins. The study also concluded that increasing gas demand in the next five to 10 years, driven by coal retirements and sustained low gas prices, may call for additional efforts to ensure reliability for gas-fired generators in some parts of the MISO footprint.

Both the MISO-commissioned studies and the EIPC study examined electric and natural gas system interactions using iterative processes. First, a simulation of the electric system was carried out with static assumptions about gas system operations, producing a set of electric system results. Then, a simulation of the gas system was carried out with static assumptions about the electric system, producing a set of gas system results. This description is a simplified characterization of the modeling processes used in these studies, but the hand-offs described are inherent in modeling gas and electric system operations with separate tools.

While there are advantages to using separate gas and electric models to answer certain questions of gas-electric system operations, there may also be benefits to modeling dynamic system interactions. As MISO plans for a future with increasing reliance upon natural gas, it recognizes that new tools may be needed to understand and plan for the growing interdependency of the two systems.

Using PLEXOS for Gas-Electric Modeling at MISO

The PLEXOS Integrated Energy Model is an Energy Exemplar optimization platform for energy market simulation and analysis. MISO has used the production cost functionality of the PLEXOS model (electric data only) for two major studies, including the Manitoba Hydro-Wind Synergy Study and the Minnesota Renewable Energy Integration and Transmission Study (MRITS).

The gas model is a relatively new addition to the Integrated Energy Model. Its initial release included state-level representation of gas production, storage, demand and transportation for the US and Canada. The second iteration of the model disaggregated these elements into separate components, interconnected via hundreds of gas nodes. Future versions of the gas model may incorporate additional granularity, such as representation of gas contracts.

The outputs of production cost simulation for the gas portion of the model can be grouped into two main buckets:

  • Physical (congestion) metrics: the duration, location and magnitude of pipeline congestion
    • For comparison, the electric-side outputs of the model include transmission line flows and binding hours.
  • Economic (cost/price) metrics: quantification of the cost to produce and transport gas; gas spot prices are provided at each gas node for every interval of the simulation
    • For comparison, the electric-side outputs of the model include locational marginal prices (LMPs).

 

The outputs for the electric model approximately parallel those of the gas model (see Figure 6.3-2) and are similar to the outputs of PROMOD, another production cost simulation tool used by MISO for long-term transmission planning. Gas and electric infrastructure interconnect in the Integrated Model via gas-fired electric generators.

Over the past several years, MISO has made significant progress on the gas-electric coordination front, enhancing system awareness, furthering coordinated operations, and facilitating cross-industry education and communication. The addition of the PLEXOS Integrated Energy Model to MISO’s planning toolkit represents another step towards better understanding and planning for future gas-electric system interactions.

This chapter provides historical context for and details on current gas-electric initiatives at MISO in the realm of long-term system planning.

Figure 6.3-2: High-level inputs and outputs for co-optimized gas-electric dispatch in PLEXOS

The results of electric production cost modeling provide insights into long-term transmission system utilization and are used to inform transmission solution development in MISO’s planning processes. Similarly, the outputs of integrated production cost modeling may be able to provide insights into long-term trends not only for electric infrastructure but also for gas infrastructure.

MISO’s ongoing analysis of the Clean Power Plan (CPP) (see Chapter 7.4, EPA Regulations – Carbon Study) incorporates this proof-of-concept gas-electric simulation tool and tests its potential to inform long-term gas infrastructure expansion needs. The application of the PLEXOS gas-electric model in MISO’s study of the CPP is a first-of-its-kind effort and MISO acknowledges the significant learning curve associated with this endeavor. MISO plans to collaborate with and leverage the expertise of its stakeholders and the broader industry throughout the process.