A limited supply of silicon used to make solar panels and a deluge of homeowners rushing to install solar power before state rebates are reduced have made it difficult for installation companies to meet demand.

These factors have helped boost the cost of solar panels in recent years, but some of the price increase may be tied to consumers offering to pay more to position themselves at the head of the line. Bargaining to move to the front of the pack is not illegal, but experts say it might not be wise to pay more if the homeowners’ states do not yet offer rebates on solar installation.

Richard King of the U.S. Department of Energy’s Solar Energy Technology Program anticipates substantial price declines soon. However, it will be a few years before new silicon plants are up and running.

In California—where 33 percent of installation costs are rebated—the average price of solar panels surged 14 percent to $37,752 during the year-over-year period ending in April, reports the state Energy Commission.   EC