Lawmakers moved two bills Tuesday that would provide incentives for residents who buy batteries to link to their rooftop solar.

The full Senate passed an amended version of House Bill 2291, which would make batteries eligible for the state’s renewable-energy tax credit while decreasing how much residents get for photovoltaic. Also on Tuesday the full House passed an amended version of Senate Bill 2738, a measure that would appropriate $50 million for a battery rebate from a program put in place to help low-income residents who cannot afford the upfront costs of PV to get solar.

Both bills would boost interest in a solar incentive program called self-supply, which requires Hawaiian Electric Co. customers wanting to install PV to buy an energy storage system. The self-supply program was one of two that the Public Utilities Commission created to replace a popular solar incentive program called net energy metering, which credited customers the full retail rate for the excess energy their systems send to the grid.

“There needs to be additional incentive for the cost burden for customers,” said Chris Debone, principal at Hawaii Energy Connection.

Both bills come with trade-offs.

House Bill 2291 would create a 25 percent tax credit for energy storage beginning in 2017 and also reduce the tax credit residents get for rooftop solar.

Residents would get a 25 percent credit for solar beginning in 2017, then 20 percent beginning in 2020 and 15 percent beginning in 2023. Solar owners currently get a 35 percent credit for their solar systems.

The energy storage tax credit would drop to 20 percent beginning in 2020 and 15 percent beginning in 2023.

The money for the rebate proposed by Senate Bill 2738 would come from the Hawaii Green Infrastructure Special Fund, which was approved by the PUC to supply $150 million for a program designed to help customers who cannot afford the upfront costs, or cannot qualify for other financing, to obtain “green infrastructure improvements,” such as rooftop photovoltaic.

“We’re taking money from the program before the program even took place,” said Richard Wallsgrove, program director at Blue Planet Foundation. “We should give the program a chance to succeed before we start raiding the funds.”

“By taking $50 million from the Hawaii Green Infrastructure Loan Program, with no repayment mechanism, this bill is saddling a subset of utility customers with lower-than-average wealth and income with the energy storage rebate program’s cost,” the state Consumer Advocate said in filed testimony.