Makoi,
Key is to understand how much cooling capacity increase you are looking for.
Are you trying to improve peak performance on hot and windy days only, or do you need to increase your performance in all situations?
Spray systems were recently discussed in a CTI paper (TP18-02 Efficient Water Use to Boost the Air-Cooled Condenser Performance) a very good document to understand the concepts better. Downloads available here:
CTI Thermal Performace papers
You can also increase performance by improving the air flow through the ACC by mitigating wind influences to increase uniformity, cleaning your bundles and of course optimizing your fan system.
Spray systems, especially aftermarket, should be used sparingly as the ACC was probably not designed for high humidity or even wet conditions inside the ACC.
A hybrid cooling system with cooling towers to address peak cooling loads such as at Commanche can have dramatic performance effects, but are of a different investment level than the above options.
