Last month, the Hawaiian Electric Companies (HECO) filed a Draft Grid Modernization Strategy describing the scope and cost of changes that will be needed to update the HECO grid to help the state meet its goal of 100% renewable energy by 2045. The proposal is HECO’s second attempt at a grid modernization plan, coming after the Hawai‘i Public Utilities Commission rejected HECO’s first proposal in an order issued earlier this year. That order found that HECO’s proposal, which had a price tag of $340 million over five years, was not cost-effective and that the proposal asserted “only an indirect link to address the primary issue currently facing Hawaii’s distribution grids, i.e., [distributed energy resources] and renewable energy integration, more broadly.”
Hawai‘i is a national leader in the integration of customer-sited private solar—in 2016, 26% of HECO’s customers were powered by renewable sources. But that success has also strained the capacity of the grid. HECO’s latest proposal acknowledges that it faces unique challenges in modernizing the grid to accommodate safely and reliably two-way power flow from many resources. HECO describes these challenges as including maintaining system reliability on HECO’s relatively small island grids without the ability to call on neighboring states to make up for generation shortfalls.
HECO’s latest proposal states that its vision for modernization is “to use advanced technologies to modernize our existing grid into a state‐of‐the‐art cyber‐physical platform . . . that will enable the integration and optimal utilization of customers’ resources through existing and new distributed energy resources . . . and demand response . . . programs.” The cost to implement the Draft Grid Modernization Strategy is estimated at roughly $205 million over six years. HECO’s plan for near-term grid modernization work calls for:
- Distribution of smart meters “surgically” rather than system-wide, primarily for enhanced sensing and monitoring purposes . . . ;
- Reliance on advanced inverter technology to enable greater private rooftop solar adoption;
- Expanded use of voltage management tools, especially on circuits with heavy solar penetration, to maximize circuit capacities for rooftop solar PV and other customer resources;
- Expanded use of sensors and automated controls at the substation and neighborhood circuit level;
- Expansion of a communication network enabling greater operational visibility and efficient coordination of distributed resources, along with smart devices placed on problematic circuits and automation for improved reliability; [and]
- Enhanced outage management and notification technology.