What is Refer-a-Friend? Refer-a-Friend is CPL Retail Energy's customer referral program. Turn your friends on to CPL Retail Energy, and you'll earn bill credits for each customer you refer. And unlike other referral programs, there's no limit to how the number of friends you can refer. With Refer-a-Friend your friends win, too, with a bill credit on their first bill when they enroll with CPL Retail Energy. Giving great rewards for referrals is just one more way we put customers first. Please visit our Refer-a-Friend page to learn more!