Are solar panel loans worth it?
A solar panel loan is worth it when the annual energy saving (typically £400 to £1,150) covers most of the yearly repayments and the interest rate is low. Low-rate or 0% deals can let solar pay for itself with little or no upfront cash. High-interest finance can wipe out the return, so always compare the total repayable with the upfront price.
When a solar loan stacks up
- The rate is 0% or low single digits.
- Your annual saving is close to or above the yearly repayment.
- You plan to stay in the home long enough to benefit after the loan ends.
- The cash price is not inflated to cover the finance cost.
The numbers to check
Compare three figures: the total amount repayable, the upfront cash price, and your estimated annual saving. If the loan adds little over the cash price and the saving roughly matches the repayment, the system is close to self-funding. SunSum's calculator gives you the saving figure to plug into this comparison.
Frequently asked questions
- What credit score do I need for solar finance?
- Most lenders look for a fair-to-good score. Better scores unlock lower rates, which materially affects whether the loan is worth it.
- Is it better to use savings or a loan?
- If your savings earn less than the loan's interest rate, paying upfront is usually better. Otherwise a low-rate loan can make sense.
Related questions
Indicative estimates based on UK average data. Last updated 27 May 2026.