I haven't heard of any 17k A/C's, but most people will simply add another AC boosting you to 30,000 btu. Other, more practical measures might include screening, slide toppers, window insulating curtains/shades, and tinting. Perhaps in a more permanent setting one might take advantage of an RV well-positioned under trees or other shade producing structures. Even so, at 100 degrees the general rule is start early (like at night) and low (as in the thermostat setting). It won't keep up, but it does help.
Some people have added (very nicely) a well placed window A/C which is powered off the 20 amp receptacle on the pedestal. I guess it's just a matter of how bad one wants to stay cool.
