Those photovoltaic solar panels popping up on rooftops all over the islands generate more than low-cost electricity.

Because of their ubiquity and direct link to Hawaiian Electric Co.’s electrical grid, they have become a flash point in the struggle between HECO’s current business model and fast-changing developments in renewable energy in Hawaii.

In 2012, the state more than doubled the number of grid-connected PV systems from the previous year, according to the Interstate Renewable Energy Council (IREC). Hawaii ranks only behind Arizona in per-capita installations through 2012, the council reports.

In order for this trend to continue, and to help Hawaii reach its goal of 70 percent clean energy by 2030, HECO and others with a vested interest in PV systems — solar power companies, PV owners, the construction unions, state regulatory agencies and environmental groups — must work together to manage this expansion for the common good.

The Legislature and Public Utilities Commission will need to balance these interests as well. However, one interest must rise above them — the long-neglected ratepayer, who has been hoping, so far to no avail, that renewable energy will lead to lower, affordable rates for all.

The latest salvo in the war among these interests was fired by a poll released Wednesday by Pacific Resource Partnership and the Sierra Club of Hawaii. The poll was commissioned to demonstrate public support for solar energy — and, no doubt, to serve the interests of solar energy advocates, including those who sell and install the systems.

The poll did its job. It showed that 96 percent of 600 respondents supported solar energy systems; 85 percent supported efforts to make the systems more affordable.

More to the political point, the poll also showed that 82 percent of respondents opposed placing an additional fee on solar panel customers.

The purpose of this fee was not defined or explained, which might explain the overwhelming support. But the question goes to the heart of the problem.

There are concerns about the costs involved in converting to renewable energy as our primary source of electricity, particularly with grid-connected PV systems. The technology is ever-changing, and technical upgrades can be expensive. HECO loses money as more PV owners generate their own electricity. Battery storage eventually may be practical for home use, allowing people to get off the grid entirely. As a traditional oil-powered utility, HECO has been less than nimble in adapting to changing conditions.

IREC is studying the costs associated with grid-connected PV systems in Hawaii. The results are expected to be released soon, and could help provide lawmakers and energy officials with some guidance in long-term energy planning.

Whatever the poll results, it’s unreasonable to expect only those unfortunate ratepayers without PV systems to make up for HECO’s loss of revenue or other costs. And additional fees imposed on PV owners cannot be so high as to discourage new installations.

One thing is clear, however. The costs can’t just be passed on to ratepayers. The PUC and the Legislature will have to ensure that HECO has as much incentive to save ratepayers money as it does to sell and distribute electricity. Only then can we proceed sensibly toward a Hawaii fueled by clean, and affordable, energy.