Power Needed For Bluetooth Transmission
It will depend on the bluetooth module you've chosen and how busy it is in your application. The Raytheon BC04 module is fairly typical:


Deep sleep  40uA 
ACL 40ms sniff  2.4mA 
SCO connection HV1  39mA 
Tx burst +4dBm  58mA



For an energy harvesting application, Bluetooth Low Energy (Bluetooth Smart) is likely to give you better results.