Brant Ward/The Chronicle

A Pacific Gas and Electric Co. executive who used a fake name in an attempt to join an online discussion group of people opposed to the utility's SmartMeter program resigned Wednesday, a company spokesman said.

PG&E had placed William Devereaux, senior director of the $2.2 billion SmartMeter program, on paid leave Tuesday after he admitted trying to join the group using the alias "Ralph." He also said he monitored other online groups of PG&E critics for several months.