Model Used in Simulations

• Transmission topology: PJM 5-bus system [3]

• Distribution topology: 11 taxonomy feeders [4]

• More than 70,000 T&D components modeled [5].

Simulation Results

Figure 1. Real power demand at the transmission buses in 

integrated T&D simulations

Figure 2. Real power demand at the transmission buses in T-only 

simulations

Figure 3. LMPs at Bus 2, Bus 3, and Bus 4 in integrated T&D 

simulations

Figure 4. LMPs at Bus 2, Bus 3, and Bus 4 in T-only simulations

IEEE ISGT 2019

Washington, D.C.

February 17–20, 2019 

NREL/PO-5D00-73296

Evaluating the Impact of Price-Responsive Load on 

Power Systems Using Integrated T&D Simulation

Himanshu Jain, Bryan Palmintier, Dheepak Krishnamurthy, Ibrahim Krad, and Elaine Hale

National Renewable Energy Laboratory (NREL)

Conclusions

Using high-resolution integrated T&D models that 

include detailed models of end-use appliances and 

PRLs, the impact of PRLs on individual customers, 

distribution feeders, and the bulk power system can 

be calculated in one simulation. Such detailed 

analysis cannot be performed with T-only models 

where load is aggregated at the transmission load 

buses. 

Abstract

This paper explores the differences between 

simulating price-responsive load (PRL) interactions 

with power systems using integrated transmission 

and distribution (T&D) models and transmission-only 

(T-only) models. This analysis uses the Integrated 

Grid Modeling System (IGMS) software to capture 

“ISO-to-appliance” simulations using a synthetic T&D 

model built on the PJM 5-bus transmission network 

with multiple full-scale taxonomy feeders that include 

physics-based models of thousands of customers 

and PRLs. The results show important differences in 

the impacts of PRLs between integrated T&D and 

T-only models.

Modeling Approach

• Integrated T&D simulations:

 Method: IGMS [1] co-simulates GridLAB-D,

MATPOWER, and FESTIV to perform quasisteady-state simulations.

 Load model: Load profiles are generated

automatically during the co-simulation.

 PRL model: Only HVACs were modeled as

PRLs using GridLAB-D’s passive controller [2].

• T-only simulations:

 Method: IGMS co-simulates MATPOWER and

FESTIV to perform quasi-steady-state

simulations.

 Load model: Aggregated, constant power loads

at the transmission buses with precalculated

load profiles are used.

 PRL model: Own-price elasticity is used to

model the price-responsive behavior of

aggregated transmission loads.

• Price input:

Real-time locational marginal price (LMP) of the

transmission bus calculated by FESTIV every 5

minutes.

Key Observations

• Real power demand profiles and LMPs are very similar

between integrated T&D and T-only simulations in the

absence of PRLs.

• Significant differences in real power demand profiles

and LMPs can be observed between integrated T&D

and T-only simulations when PRLs are present.

• Few LMP spikes occur in the T-only simulations; no

such spikes occur in the integrated T&D simulations.

 Price spikes occurred because price elasticity caused

loads to increase in response to reduced real-time

LMPs, and a small amount of load was shed (4 MW at

5:30 p.m.) and reserves were deployed (at 8:00 p.m.)

to meet the increased demand.

References

[1] B. Palmintier et al. 2017. “IGMS: An Integrated ISO-to-Appliance 

Scale Grid Modeling System.” IEEE Trans. Smart Grid 8, no. 3 (May):

1,525–1,534.

[2] “Transactive Controls—GridLAB-D Wiki.” [Online]. http://gridlabd.shoutwiki.com/wiki/Transactive_controls. Accessed September 14,

2017.

[3] F. Li and R. Bo. 2010. “Small Test Systems for Power System 

Economic Studies.” 2010 IEEE PES General Meeting Proceedings: 

1–4.

[4] K.P. Schneider, Y. Chen, D.P. Chassin, R. Pratt, D. Engel, and S. 

Thompson. 2008. Modern Grid Initiative Distribution Taxonomy Final

Report (PNNL-18035). Richland, WA: Pacific Northwest National 

Laboratory.

[5] H. Jain, B. Palmintier, I. Krad, and D. Krishnamurthy. “Studying the

Impact of Distributed Solar PV on Power Systems Using Integrated

Transmission and Distribution Models.” 2018 IEEE PES T&D

Conference and Exposition Proceedings.

This work was authored by the National Renewable Energy Laboratory, operated by Alliance for Sustainable Energy, LLC, for the U.S. Department of Energy (DOE) under Contract No. DE-AC36-08GO28308. Funding provided by U.S. Department 

of Energy Office of Energy Efficiency and Renewable Energy Solar Energy Technologies Office and Grid Modernization Laboratory Consortium. The views expressed in the article do not necessarily represent the views of the DOE or the U.S. 

Government. The U.S. Government retains and the publisher, by accepting the article for publication, acknowledges that the U.S. Government retains a nonexclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published 

form of this work, or allow others to do so, for U.S. Government purposes. Authors: Please replace the funding statement with the new required notice. This can replace both statements currently included on the bottom of the poster.