CEDAR RAPIDS — Municipal solar projects in Cedar Rapids and Hiawatha save taxpayers thousands of dollars each year, a new report from the Office of the State Auditor found.Cedar Rapids’ municipal solar projects save about $5,000 a year and are projected to save $100,000 over a 20-year period, the report said.Hiawatha’s solar project saves about $37,000 a year and is projected by the report to save $737,000 over 20 years.The report, released late last week, randomly chose 27 public-sector solar projects across Iowa to feature.