In a filing made public Tuesday, a coalition of solar energy groups asked state regulators to increase the limit on photovoltaic systems allowed to send excess power to the grid.

In October the PUC placed a 35-megawatt cap on the so-called “grid supply” PV systems. The groups said the limit could be reached next month.

The PUC said it placed the limit on new PV systems to make room on the grid for other sources of renewable energy. The limit was adopted at the same time the PUC ended a solar-energy incentive program known as net energy metering. It was replaced with grid supply.

The grid-supply program credits solar energy customers about 8 cents lower per kilowatt-hour than the full retail rate. NEM paid the full retail rate. The PUC has a second solar program aimed at customers who buy battery systems and don’t feed power to the grid.

The Hawaii PV Coalition, the Hawaii Solar Energy Association, Sunpower Corp. and The Alliance for Solar Choice said a recent uptick in grid-supply applications might fill the remaining capacity on some islands as early as June. The groups said the wave of applications will likely fill any remaining capacity on all islands by the beginning of August.