Investing in the Future

Varentec Grid Optimization Project

Project Scope

In 2016, Hawaiian Electric Company and Santa Clara-based Varentec, Inc. started the first phase of a pilot project to install and validate the performance of Varentec's technology for ensuring grid reliability and efficiency while allowing more private rooftop solar systems to be added to island grids. Hawaiian Electric Company installed sixty of Varentec's Edge of Network Grid Optimizers™ (ENGO) to minimize voltage fluctuations along the distribution grid and maintain safe, reliable operations along a neighborhood circuit with a high level of distributed solar generation. The circuits chosen for the pilot project were Aalapapa (Lanikai) and Enchanted Lakes in Kailua. These circuits were identified for this project because of their high/rising level of rooftop solar penetration and its mixed characteristic of 4 kilovolt (kV) and 12 kV service lines.

Hawaiian Electric Company will be applying this innovative solution to test its technology in different circuit conditions with high/rising level of rooftop solar generation. Starting in September 2017, Hawaiian Electric Company crews will be installing these devices in Makiki/Manoa, Waimanalo and Kahuku/Laie.


A key challenge resulting from a large number of rooftop solar systems feeding excess electricity into a neighborhood circuit is increased voltage instability for all customers, with or without rooftop solar. Higher than allowed voltage can trip off rooftop solar systems, damage home appliances, and could endanger utility crews working on the grid.

Hawaiian Electric and Varentec believe the unique capabilities of this technology can address voltage issues at a lower cost to customers than other alternatives considered.

Anticipated Benefits

  • Improved voltage management and power quality for circuits with installed devices.
  • Potential to add more rooftop solar systems to the grid.
  • Innovative solution to lower the cost and increase the speed at which rooftop solar can be added to the grid.

Varentec Device

Community Impacts

  • Each device is approximately 27-inches x 16-inches and is mounted around 10-feet off the ground on existing overhead utility poles near the electrical transformer.
  • Crews will be working on each pole for a short time (1-2 hours) before proceeding to the next site.
  • Brief parking restrictions on residential streets may be needed for bucket trucks and device installation.
  • There will be no interruptions to electric service as a result of this work.

Installation Schedule

  • Equipment installation will occur in September for Makiki and Manoa.
  • Equipment installation will occur tentatively in October for Waimanalo.
  • Equipment installation will occur tentatively in October/November for Kahuku/Laie.