Run one ac unit at a time (one compressor at a time) instead of both to save money and energy. In large homes when there are two air conditioning units, only should be left on! One unit works just as well as two unites. It still provides a comfortable atmosphere as well!
Simple tasks such as turning off appliances, computers, etc. can help you save money! They are unable to draw power and waste more energy! It is a simple solution to a complex problem, and along with helping your wallet.