Parking it outside is perfectly fine. You don't line in an extreme climate (and as long as you keep your SOC above about 30% battery conditioning would take place anyway). Probably 90% of people park their cars outdoors while at work.
The 110v outlet isn't going to add much power if you're only there 5 hours a day. How far is your commute? 5 hours is only going to add about 25-30 miles of range. Depending on the price you're paying for power, 5 hours or 7.5 kw will add about 0.85 to your power bill every day. Commuting 22 days a month means the amount of juice you would get at work for $40 will cost you about $18.70 a month if you're plugged in at home.