Bell, who received a $5 million signing bonus after he was taken by the Pirates in the second round of the 2011 Draft, clubbed a three-run homer in the top of the fifth inning to cut the Power's deficit to 7-4. The blast raised his team-high RBI total to seven for the season.
Ranked as MLB.com's No. 69 prospect, Bell also singled and scored in the eighth to lift his average to .268 over six career games. The 19-year-old switch-hitting outfielder has doubled twice, struck out nine times and walked once in 26 at-bats.
Power starter Mike Jefferson (1-1) yielded six runs -- five earned -- over 3 1/3 innings as West Virgina fell to 1-6.
Jared Simon led the way for the Tourists, going 2-for-4 with three RBIs. Samuel Mendel also collected two hits, including a solo homer, to raise his season-opening average to .440.
Geoff Parker (1-1) picked up the win in relief, giving up one run on one hit in 2 1/3 innings for the Tourists.