TVA Transmission Service Guidelines and Rates for Fiscal Year 2009 TVA has revised the TVA Transmission Service Guidelines and the rates for transmission and ancillary services. The Guidelines and rates (effective October 1, 2008) can be viewed at TVA Guidelines.   Change in Pricing of Non-Firm Transmission Service Effective October 1, 2008, TVA has begun using on-peak and off-peak pricing for non-firm point-to-point transmission service.