Hawaiian Electric Co. said it hopes to cut residential customer bills by “more than 20 percent” by 2030 while getting 65 percent of its energy from renewable sources, according to a plan filed Tuesday with the state Public Utilities Commission.

HECO envisions a tripling of solar power generation in Hawaii but said the cost of upgrades to the grid needed as a result of the added renewable energy may have to be paid for by a one-time charge to customers installing new PV systems.

HECO filed a 515-page “Distributed Generation Interconnection Plan” with the PUC late Tuesday and the PUC released it to the public. The distributed power plan is one of five plans HECO filed with the PUC on Tuesday.

The PUC made the documents available to the public on their website after the utility’s submission. The documents can be viewed at http://puc.hawaii.gov/news/

The filing is in response to orders issued by the PUC in April after HECO’s original strategy for meeting the energy needs of customers over the next 20 years was rejected.

HECO said the increase in solar power will be done in a way that protects the “safety and reliability of the grid” and “fairly allocates costs of the grid to all customers.”

Before the plan was submitted, HECO spokesman Darren Pai, said, “Our energy environment is changing rapidly and we are changing with it to meet our customers’ evolving energy needs. We’ve developed plans that outline specific actions for adding significantly more renewable energy and lowering costs for our customers. We look forward to filing these plans with the Public Utilities Commission and sharing them.”