The above posts are right on the money. The TCH, like the Prius, does not have a belt driven AC. It is a directly driven electric compressor. Using the AC will affect your city fuel efficiency by drawing power from the battery pack, often very quickly, on a hot summer day. Of course, this means the ICE must run more often to charge the battery pack. I have noticed about 10% FE reductions here in Dallas over the recent 3 weeks of 100+ temps.

Alden Bowles
2005 Toyota Prius II HSD