TEPCO, under the terms of the deal, gets another 400,000 tons of liquefied natural gas from the Wheatstone project in Australia each year, bringing its total uptake to 4.2 tons per year under the terms of a 20-year agreement.
Japan last year said it would take on more natural gas following a meltdown at one of its nuclear reactors.
In September, the Australian government issued a positive environmental assessment for the Wheatstone natural gas project. That project consists of facilities that could produce nearly 9 million tons of liquefied natural gas per year for Chevron.
Chevron Australia Managing Director Roy Krzywosinski said more than 80 percent of the LNG from Wheatstone is covered under long-term deals with Asian customers.
"These agreements continue to demonstrate Wheatstone is well-placed geographically to meet the Asia Pacific region's demand for a safe, reliable and cleaner-burning source of energy," he said in a statement.
Japan last month shut its last operating nuclear reactor for maintenance, leaving the country without nuclear power for the first time in more than 40 years.
Japanese Prime Minister Yoshihiko Noda last weekend ordered the restart of two reactors, however.