1. Energy regenerates at a rate of 1 energy every 30 minutes. The timer under the energy bar will tell you how long you have to go until you get your next energy.

2. Your friends can gift you energy if your game is connected to Facebook. You request energy from your friends by clicking on the "plus" symbol next to the energy bar on your game screen. You can only use gifted energy once you are completely out of energy by tapping the "Use Gifted Energy" button either in a level, or from the meta map by clicking on the energy icon at the top of your screen. The number next to the "energy" symbol shows how much gifted energy you have to use.  

3. You can also refill your energy for Dinero. If you don't have enough Dinero, you can purchase some by visiting the in-game bank or by watching video ads under the "Free Dinero" tab. 

4. Dinero can also be earned by achieving a certain score on select levels throughout the game. Dinero can only be earned once per level.