PRECISE: PREconfiguring and Controlling Inverter SEt-points

2019 R&D 100 Winner

NREL has created PRECISE™—PREconfiguring and Controlling Inverter SEt-points—to help utilities quickly establish optimal inverter settings for distributed solar energy.

PRECISE combines detailed distribution system modeling with analyses of grid conditions to provide custom solutions to grid stability. This functionality has won PRECISE an R&D 100 award and has helped customers safely install more solar energy across the world.


With PRECISE, utilities can streamline the integration of new customer solar power. PRECISE uses the customer’s address and a built-in model of that customer’s distribution feeder to calculate the advanced inverter modes that will provide grid support and minimize energy curtailment.

New customers can interconnect their solar quicker, and utilities can automate a process that would take twice as long otherwise.

Graph illustration that shows the Precise Tool operating in the optimal range between customer loss and utility loss.

PRECISE creates value for both customers and utilities. Optimal inverter settings strike a balance between curtailing customer energy and cost-effectively using customer devices for grid stability.

By programming the best settings for each circumstance, utilities can keep solar running on their systems without risking stability issues.


PRECISE uses quasi-static time series simulations, alongside mathematical optimization, to identify optimal inverter modes. PRECISE can be considered in three separate modules.

Distribution Power-Flow

Utilities are able to interface with local distribution system detail using PRECISE. Select features include:

  • Visibility of network topology and geographic location of solar systems
  • Capability to perform power-flow analysis
  • Conversion tool from GIS/Syngergi to OpenDSS
  • Choice of advanced inverter modes for analysis.

Inverter Optimization

Users can program the constraints and physical hardware limitations, which lead to PRECISE’s identification of those advanced inverter modes. Features include:

  • Adherence to grid interconnection standards
  • Adherence to limitations from power-factor limits or reactive power limits
  • Parameterization of weather events and local grid conditions.

Visualization and Data-Ingestion

PRECISE is equipped with a user interface that makes data input, such as a solar interconnection application, easy. Users can visualize the effects of specific inverter modes and device management decisions.

Download the PRECISE white paper to learn more.



Adarsh Nagarajan

Group Manager