Oil tankers sit offshore in the San Francisco Bay Area, the United States, April 26, 2020. More than 30 oil tankers carrying over 20 million barrels of crude oil are parked between Long Beach and the San Francisco Bay Area. (Photo by Li Jianguo/Xinhua)

An oil tanker sits offshore in the San Francisco Bay Area, the United States, April 26, 2020. More than 30 oil tankers carrying over 20 million barrels of crude oil are parked between Long Beach and the San Francisco Bay Area. (Photo by Li Jianguo/Xinhua)

An oil tanker sits offshore in the San Francisco Bay Area, the United States, April 26, 2020. More than 30 oil tankers carrying over 20 million barrels of crude oil are parked between Long Beach and the San Francisco Bay Area. (Photo by Li Jianguo/Xinhua)

Oil tankers sit offshore in the San Francisco Bay Area, the United States, April 26, 2020. More than 30 oil tankers carrying over 20 million barrels of crude oil are parked between Long Beach and the San Francisco Bay Area. (Photo by Li Jianguo/Xinhua)