Sunrun, one of the nation’s largest solar installers, is telling its thousands of Long Island customers to opt out of LIPA’s new time-of-day rates, but PSEG Long Island says not so fast.

In a message to customers this summer, Sunrun, which has been marketed through Costco stores and offers primarily leased solar systems, said the new rates will likely cost its customers money, with few exceptions.

"This new rate could result in a higher utility bill for you," Sunrun said, urging them to check their bill to see if they’ve been switched to rate number 194 — the new standard rate from PSEG. "In order to maximize potential savings, we strongly encourage you to opt-out of the new time-of-day off-peak rate and choose to remain on rate 180," a flat rate.

However, PSEG Long Island, which operat

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