A question came up on the Lotus Talk forums about installing AC in a '70 Lotus Europa. While most Locost drivers won't need AC, those of use building cars that include a roof, doors and windows might find AC a necessity. I expect that I will since my build is also based off the Lotus Europa, like the original poster on Lotus Talk.
A quick search of the forums here comes up with three threads that I could find. The first thread here
is also part of the "In Theory" section, but that thread is focused on ideas for providing heat. The second thread is here
in the BEC section, but immediately goes off topic. The third thread is over here
in "Off Topic" and is a humor thread.
The AC problem seems to come in two distinct flavors. The first is more straightforward and would involve finding components that could be adapted from a car engine & donor (or aftermarket supplier like Vintage Air) and packaged reasonably into a Locost.
The second problem is more complex and is a closer fit to the problems faced with a BEC, or in my case, a Lotus Europa. A good place to start researching solutions is this
thread from the diyelectriccar.com forums. This may sound like a stretch, but the builders there face similar problems when trying to add AC to their vehicles. Not being able to just bolt on an AC compressor on to the front of an engine seems to be the biggest problem. Limited available electrical power is also a common constraint. The thread there has some good ideas that I will be digging into more when the time arrives.