<?php
$now = new DateTime();
$query = new EntityFieldQuery();
$query
   ->entityCondition('entity_type', 'node')
   ->fieldCondition('field_expirationdate', 'value', $now->format('Y-m-d'),'<')
   ->addMetaData('account', user_load(1));

$result = $query->execute();
drush_print_r($result);
?>