Energy Harvesting

Hello,

I have a requirement to develop a wireless sensor network. Another requirement is that the sensor nodes should have energy harvesting capabilities with battery backup. The actual requirement is "battery or other energy components should not have to be replaced for atleast 15 years." I was researcing Google for energy harvesting technologies. So, can I design a system using TI Products? What are those components? Also, what are the advantages of actually using TI Products over what ATMEL or Microchip or Linear Technology offers? I appreciate your help and providing any information possible. Awaiting your reply. Thank you.