MTEP15 Chapter 6.2: Long Term Resource Assessment

MTEP15 Chapter 6.2: Long Term Resource Assessment

The Long-Term Resource Assessment (LTRA) examines the balance between projected resources and the projected load. These resources are compared with Planning Reserve Margin Requirement (PRMR) to calculate a projected surplus or shortfall.

MISO forecasts the reserve margin will drop below the PRMR of 14.3 percent beginning in 2020, and will remain below the PRMR for the rest of the assessment period (Table 6.2-1). Falling below the PRMR signifies that the MISO region is projected to operate at a reliability level lower than the one-day-in-10 standard in 2020 and beyond. MISO anticipates the projected margin shortfall will change significantly as Load Serving Entities and state commissions solidify future capacity plans.

This is an expected result, as 91 percent of the load in the MISO footprint is served by utilities with an obligation to serve. This obligation is reflected as a part of state and locally jurisdictional integrated resource plans that only become certain upon the receipt of a Certificate of Public Convenience and Need (CPCN). Five years is sufficient lead time for Load Serving Entities to plan, build and operate new resources to meet the projected shortfall in 2020 and beyond.

In GW (ICAP) PY 2016/17 PY 2017/18 PY 2018/19 PY 2019/20 PY 2020/21 PY 2021/22 PY 2022/23 PY 2023/24 PY 2024/25 PY 2025/26
(+) Existing Resources 151.9 151.5 151.2 150.5 150.4 150.4 150.4 150.4 150.4 150.4
(+) New Resources 0.7 2.1 2.1 2.5 2.6 2.6 2.6 2.6 2.6 2.6
(+) Imports 4.3 4.3 4.3 4.3 4.3 4.3 4.3 4.3 4.3 4.3
(-) Exports 3.8 2.8 2.8 2.8 2.8 2.8 2.8 2.8 2.8 2.8
(-) Low Certainty Resources 0.6 0.5 1.1 1.0 2.3 3.0 3.7 4.4 5.7 8.6
(-) Transfer Limited 3.4 3.0 2.6 1.9 1.6 1.4 1.2 1.0 0.8 0.6
Available Resources 149.1 151.5 151.1 151.5 150.5 150.1 149.6 149.1 148.0 145.3
Demand 128.9 130.4 131.2 132.4 133.3 134.1 134.9 135.9 136.6 137.7
PRMR 147.3 149.0 150.0 151.3 152.3 153.2 154.2 155.3 156.2 157.4
PRMR Shortfall 1.7 2.6 1.1 0.2 -1.8 -3.2 -4.6 -6.2 -8.2 -12.2
Reserve Margin Percent (%) 15.6% 16.3% 15.1% 14.5% 13.0% 11.9% 10.9% 9.7% 8.3% 5.5%
Table 6.2-1: MISO anticipated PRMR details (cumulative)

The anticipated PRMR shows significant improvements from the 2014 LTRA results, which projected a shortfall against the reserve requirements of 2.3 GW in 2016. The conclusions from the long-term resource assessments are:

  • All zones within MISO are sufficient from a resource adequacy point of view in the near term, when considering available capacity and transfer limitations. Regional shortages in later years may be rectified by the utilities and, as such, do not cause immediate concern.
  • The change in LTRA results was driven primarily by a combination of an increase in resources committed to serving MISO load and a decrease in load forecasts.
  • The increase in committed resources reflects action taken by MISO load-serving entities and state regulators to address potential capacity shortfalls.
  • MISO anticipates that each zone within the MISO footprint will have sufficient resources within their boundaries to meet their Local Clearing Requirements or the amount of their local resource requirement, which must be contained within their boundaries.
  • Several zones are short against their total zonal reserve requirement, when only resources within their boundaries or contracted to serve their load are considered. However, those zones have sufficient import capability and the MISO region has sufficient surplus capacity in others zones to support this transfer. Surplus-generating capacity for zonal transfers within MISO could become scarce in later years if no action is taken in the interim by MISO load-serving entities.

Policy and changing generation trends continue to drive new potential risks to resource adequacy, requiring continued transparency and vigilance to ensure long-term needs.

  • MISO projects that reserve margins will continue to tighten over the next five years, approaching the reserve margin requirement
  • Operating at the reserve margin creates a new operating reality for MISO members where the use of all resources available on the system and emergency operating procedures are more likely. This reality will lead to a projected dependency in the use of Load Modifying Resources (LMR), such as Behind-the-Meter Generation (BTMG)and Demand Response (DR).


At the end of 2013 MISO and Organization of MISO States (OMS) conducted a Resource Adequacy survey of load-serving entities to help bridge the gap of limited visibility that exists between the annual Module E Tariff process and Forward Resource Assessment. MISO finished the survey in June, 2014, and it was instrumental in the development of the Long-Term Resource Assessment and the Resource Adequacy outlook for the MISO region.

Demand Growth

In 2016, MISO anticipates that the MISO Region’s coincident demand will be 128,885 MW, which is a 50/50 weather-normalized load forecast.

Load-serving entities submit demand forecasts for the upcoming 10 years. MISO utilizes these forecasts to calculate a MISO business-as-usual load growth. Based on these forecasts, MISO anticipates a system-wide average growth rate of 0.8 percent for the period from 2015 to 2025.

In 2016, MISO anticipates that the MISO Region’s coincident demand is projected to be 128,885 MW, which is a 50/50 weather-normalized load forecast


In 2016, MISO expects a total of 143,877 MW of Anticipated Capacity Resources to be available on-peak. MISO’s current registered capacity (nameplate) of 173,289 MW steps down to Existing-Certain Capacity Resources of 141,100 MW by accounting for summer on-peak generator performance, transmission limitations and energy-only capacity (Existing-Other Capacity Resources). MISO only relies on 141,100 MW towards its PRMR to meet a loss-of-load expectation of one day in 10 years.

In 2016, MISO expects a total of 143,877 MW of Anticipated Capacity Resources to be available on-peak

BTMG, Interruptible Load (IL), Direct Control Load Management (DCLM) and Energy Efficiency Resources (EER) are eligible to participate as registered LMRs. All of these are emergency resources available to MISO only during a Maximum Generation Emergency Event Step 2b per MISO’s Emergency Operating Procedures. MISO assumes the 4,400 MW of BTMG dropping to 4,200 in 2020 and 6,400 MW of LMR DR that was qualified in the 2015 Planning Resource Auction to be available throughout the assessment period.

This year, MISO and OMS completed the second iteration of the Resource Adequacy Survey. In the survey, resources that were identified to have a low certainty of serving load were not included (Table 6.2-1).

Through the Generator Interconnection Queue (GIQ) process, MISO anticipates 2,584 MW of future firm capacity additions and uprates to be in-service and expected on-peak during the assessment period (Figure 6.2-1). This is based on a snapshot of the GIQ as of June 2015 and is the aggregation of active projects with a signed Interconnection Agreement.

Figure 6.2-1: Anticipated resource additions and uprates (cumulative) in the MISO Region

Figure 6.2-1: Anticipated resource additions and uprates (cumulative) in the MISO Region

Imports and Exports

MISO assumes a forecast of 3,157 MW of capacity from outside of the MISO footprint to be designated firm for use during the assessment period and cannot be recalled by the source transmission provider. This capacity was designated to serve load within MISO through the Module E process for summer 2015. It’s assumed that the firm imports continue at this level for the assessment period. MISO assumes a forecast of 3,806 MW of firm capacity exports in year 2016 to regional transmission operator PJM based on PJM Base Residual Auction cleared results. Exports are projected to decrease to 2,780 MW in 2017 and remain at that level for the rest of the assessment period.

When comparing reserve margin percent numbers between Table 6.2-1 and the NERC LTRA, the percent for each planning year will be slightly lower in the NERC LTRA because of differences in the reserve margin percent calculation. MISO’s resource adequacy construct counts DR as a resource while the NERC calculates DR on the demand side. While the percent will be slightly different, the absolute GW shortfall/surplus is comparable between the two.