<prompt> Human: Last year I installed solar panels on my house. I paid 13 up front, and financed the other 23. The first loan was interest free for a year, basically meant to give me time to file my taxes and pay it off with the rebate which was for 13 cost of panels. Thats now all taken care of.Im not sure what to do about the second loan. I have 13 left at 2.99 interest for 7 years. For the next 10 years, I receive a 250 credit per 1000kwh generated, so the solar panels will pay themselves off in that 7 year time frame. However I have the cash to pay off the loan now, meaning Id get the remaining 9 years of credits to invest and save that 3 interest.Ultimately after the full 10 years of credits, remaining tax incentives, etc Ill have paid 200 out of pocket for 30 years of electricity if I let the credits pay the loan and save the rest. But I dont like debt, and I kind of want to pay it off and be done with it. My only debt is this loan and my mortgage. I got burned by paying off my student loans in 2 years instead of 15 and not building credit when I was younger, so I had to build that credit with cards before I could get approved for a mortgage. My problem is that I tend to be afraid of debt when, being young, it might be good to keep it and build my credit a bit more with such an easy loan.I guess I just need some advice from more experienced folks! What should I do?Assistant: This reads like a question out of a math textbook. Now, calculate the value of the original loan. No debt is the best debt. Pay it off now. Depending, of course, on the size of your cushion of remaining cash, your expected expenses over the near term, and your comfort level with those 2 numbers for the period of time it will take to get back to where you are now before paying it off. Human: Ill make more money paying it off now for sure, Ive done that math a few times. Ive got an 18 month cushion regardless of this payoff self employed so its necessary, and while my credit is good I dont have a lot of it. My entire credit history is 1 credit card, this solar loan, 2 years of student loans paid off 3 years ago and 1 year of mortgage...thats all the debt Ive ever had.So I guess Id be sacrificing around 2,000 in compound interest to add 7 years of monthly payments to my credit history. Im just not sure if its worth it to build credit for the future since Im only a few years out of college.Assistant: you already have a mortgage, what do you care so much about your credit score for? If you use your credit card and pay everything on time your credit score should be fine for whatever you want to do Id think. Human: i own and co-own 2 businesses, wih 2 more openinglaunching in 2015. A good strong credit score will keep my options open should I need to borrow to fund growth in the future. Id also like to get into rental properties in a couple years, so itll help there too. Ultimately its just another tool in the shed that I want to keep as sharp as possible  <response>: fair enough. I still find it hard to believe that carrying a loan is going to make enough of a difference thats it worth giving up 500. Admittedly, though, I dont know that much about credit scores. 