Thomas Barwick/DigitalVision via Getty Images Overview I really enjoy seeing the dividend income in my portfolio grow over time with the least amount of effort on my end. This enjoyment prompts me to spend a lot of time looking for the next opportunity to increase my annual passive income. I believe that utilities offer a ton of opportunities at the moment as these businesses are typically very sensitive to interest rate changes. Utility-based companies often depend on attractive debt financing to fund  ...