This is a confusing topic in our local industry as solar companies from neighboring states have flooded into the Idaho market and with that has come quite a bit of misleading statements regarding the available incentives. Here in Idaho, a homeowner who installs solar is qualified for a 30% federal tax credit (based on retail project costs and is dollar for dollar against owed liability) which is structured on a 5-year carryforward basis to allow a consumer to reap all value from the credit within 5 years on their federal tax filings.
The state of Idaho also offers up to a $20,000 state income deduction. This deduction typically equates to a cash value ranging from $1,200 - $2,000 on their state tax filing with a fixed 40/20/20/20 structure to recapture that value. Essentially this recovers the taxes that are included in the project over a 4-year period based on the consumer's tax bracket. The state of Idaho nor Idaho Power currently offers any rebates for solar installations so if that is a message you are hearing from a prospective contractor be very cautious. The US Department of Energy provides all consumers with an easy guide to all available incentives at dsireusa.org.