DENVER – UPS' newest trucks powered by compressed natural gas (CNG) are scheduled to hit the streets of Denver. Of the 300 new vehicles ordered last year, 43 now are making deliveries in the city. The vehicles were scheduled to be unveiled at a media event today in Commerce City, Colo., however the unveiling was postponed "due to inclement weather."

The vehicles were expected to be unveiled at 8 a.m. MDT Friday in Commerce City, Colo., with the following officials in attendance:

• U.S. Rep. Ed Perlmutter. 

• Commerce City Mayor Paul Natale. 

• Commerce City Councilwoman Reba Drotar. 

• Commerce City Councilman Jason McEldowney. 

• UPS automotive experts. 

Part of an order placed last May, the CNG vehicles will allow UPS to further reduce its dependence on gasoline and diesel while lowering its carbon footprint, according to the company. UPS already operates the largest private fleet of alternative fuel vehicles in the delivery industry - 1,819 in total with these additions. 

Over the past month, the 300 CNG trucks have been deployed to seven cities in the U.S.:

• Denver, Colo. (43).

• Atlanta, Ga. (46).

• Oklahoma City, Okla. (100).

• Sacramento, Calif. (21).

• San Ramon, Calif. (63).

• Los Angeles, Calif. (9).

• Ontario, Calif. (18).