Do I need an Internet connection for LaCie Fuel to work?

No. You do not need Internet connection to be able to access data from the LaCie Fuel. The LaCie Fuel is its own wireless network, so your iOS devices or other Wi-Fi enabled devices can access the LaCie Fuel without Internet access. To be able to surf the web or check email while connected to the LaCie Fuel, you must connect/reconnect to an existing WiFi network in concurrent mode. See this article for instructions on connecting in concurrent mode.