Chelsea Harvey for The Washington Post:   On Friday, United Airlines will launch a new initiative that uses biofuel to help power flights running between Los Angeles and San Francisco, with eventual plans to expand to all flights operating out of LAX. It's the first time an American airline will begin using renewable fuel for regular commercial operations, and the occasion is part of a bigger movement when it comes to clean transportation in the U.S.

The renewable fuel used to power United's planes will be coming from a Los Angeles refinery operated by AltAir Fuels, which is using the facility to produce both renewable jet fuel and diesel fuel using a technology developed by Honeywell UOP, a major supplier and technology licenser in the petroleum industry. Back in 2013, AltAir and United announced their partnership, in which United will purchase up to 15 million gallons of biofuel over a three-year period.

Friday's launch will be the first application of that agreement. The flights will use a mixture of 30 percent biofuel and 70 percent traditional fuel, and United says that the biofuel will help reduce greenhouse gas emissions by about 60 percent compared with regular fuel.  Cont'd...