Today’s high interest rate environment has led to higher borrowing costs for consumers, but there is a silver lining for savers: If they can find the right savings product, their idle cash can generate significant income. The Fed’s key interest rate target range is 5.25% to 5.5%, the highest level in 22 years. The central bank’s base rate affects a range of consumer goods, including the annual interest rate assessed on credit card debt and the annual rate of return paid by banks on savings. Today, a high-yield savings account or certificate of deposit can earn an annualized return of up to 5%, which is well above the national average of 0.63%, according to Bankrate.com. A recent Santander USA study titled “Pathways to Prosperity” shows that for many people, high-yield savings accounts have become a source of passive income in a rising interest rate environment, but few appear to be taking advantage of this source. The firm found that even as interest rates rise, about 6 in 10 middle-income Americans still keep money in low-yield accounts. To be sure, that’s a slight improvement from the seven out of 10 that did the same thing in the second quarter last year. Santander U.S. CEO Tim Winnes said much of this points to a lack of education, such as the impact higher interest rates might have on savings, or the types of savings products available to consumers. Additionally, the company found that four out of five Americans find opening a new bank account a time-consuming burden. “There’s a general lack of awareness about the interest earned,” Winnis said. “Alternatively, there’s a view that the switching costs or friction associated with making the change is more about the work than the benefits of getting higher rates.” “I think both of those are wrong assumptions,” he said. The CEO recommended investors lock in higher interest rates for six to 12 months before they start to fall, which many investors expect could happen as early as September. While interest on a high-yield savings account can rise or fall based on the Federal Reserve’s benchmark interest rate, interest on a CD can be fixed for a period of time, meaning the earnings won’t fluctuate during the lifetime. As of Friday, Bread Financial’s 1-year CD yield was 5.15%. Meanwhile, LendingClub offers a 1-year CD with an APR of 4.4%, and its high-yield savings account has an APR of 5%. —CNBC’s Darla Mercado contributed to this report.