On Tuesday, Climate United, one of the country’s newly established nonprofit ​“green banks,” unveiled a $250 million plan with electric truck-charging startup Forum Mobility aimed at overcoming those barriers. The money will help secure low-cost financing for up to 500 U.S.-built Class 8 electric trucks — the largest such order of electric trucks in the country — for small freight companies and independent truckers serving California’s busiest and most heavily polluted seaports.

The ports of Long Beach and Los Angeles handle about 30 percent of U.S. container imports, and about 80 percent of the ​“drayage” trucks that haul those containers to inland distribution centers are owned by small fleet operators and independent drivers, said Beth Bafford, CEO of Climate United.