Dive Brief:

• Hawaiian Electric Co. has filed its latest Power Supply Improvement Plan (PSIP) with the state's Public Utilities Commission, outlining how it intends to reach 100% renewables by 2040 — five years ahead of the state's mandated goal.
• The plan calls for HECO to provide 48% renewable power by 2020, without the use of imported liquefied natural gas. The PSIP aims for the addition of 360 MW of grid-scale solar, 157 MW of wind energy, and 115 MW from demand response programs by 2050. 
• The new PSIP is HECO's third attempt at a 100% renewable energy plan. Regulators rejected the first in 2015 for a lack of specificity and the second version, filed in April 2016, was rendered moot when the PUC turned away NextEra Energy's bid to buy the utility. 

Dive Insight:

HECO's new plan filed with regulators outlines how it will use demand management, battery storage and biofuels to avoid importing liquefied gas supplies and phase out oil generation, ultimately moving faster than the state has mandated towards an all-renewables supply mix.

​HECO's plan envisions continued growth of private rooftop solar and the use new inverters and control technology to help integrate 165,000 private systems by 2030. That would more than double the number of systems on the utility's grid today.

In addition to eliminating proposals for LNG imports, the utility also eschewed a plan for inter-island transmission cables. Connecting now-separate Hawaiian grids could provide benefits, the PSIP said, but one of the goals of the report was to design a 100% renewables mix without them. 

Under the state's renewable energy mandate, HECO is supposed to reach 40% renewables by the end of 2030, but said its plan targets 72% in that same timeframe. HECO's proposal estimates that the renewable energy capacity after 2030 could exceed 100% of demand when taking into account customers’ generation of electricity for their own use, "as well as the anticipated widespread use of battery storage."

By 2020, the island of Molokai will be 100% renewable, through a proposed mix of solar, wind, battery storage and biofuels. In that same period, Hawaii Island is forecast to reach an RPS of 80%, Maui 63%, and 40% on Oahu, where most of the state's population is located.

However, the utility warned that investments in grid infrastructure, as well as rising oil prices, "are expected to increase the typical residential bill over the next several years," before customers see them gradually decline beginning in the mid-2020s.

The PSIP was compiled with input from various stakeholders, including the state's consumer advocate and executive energy office. A comment period on the proposal is now open, with final position statements from parties due Feb. 13, after which regulators will decide on the plan.