25 Pa. Code § 961.10
(c) The minimum rate of interest to be paid on a loan shall be 1%. The maximum rate of interest may not exceed the following:
(e) In establishing the interest rate of a loan, the Board will consider the ultimate effect that the financing of a project’s costs will have on the rates customers will have to pay. A rate increase will be compared with local incomes and ability to pay in determining a loan’s interest rate. In the process of setting an interest rate, the Board may consider factors including, but not limited to: