I am trying to calculate my Utility Expenses related to my consulting work from my home. Can I include my loan payments for my solar panels?

[Hal_Al]

No.  That's not utilities.

A second question would be can I deduct the loan interest.  Probably.  It would have to qualify as a 2nd mortgage.  Home improvement loans usually qualify. See rules at https://www.irs.gov/publications/p936

Other references:

https://www.rocketmortgage.com/learn/mortgage-interest-deduction#:~:text=What%20Is%20The%20Home%20Mo....

https://www.energysage.com/solar/financing/secured-or-unsecured-solar-loan/#:~:text=Many%20secured%2....