Scattered throughout Kazakh there are fifteen different energy upgrades to collect. Ten of these will upgrade your maximum capacity for energy and the remaining five will increase the recharge rate of your energy meter. They are marked on your map by a yellow bar with an arrow on them. If you are unsure of the icons, bring up the map and press  to bring up the legend with a list of all icons there. These will only show on your map when you are relatively close and have uncovered the fog of war. Unfortunately, the health and energy upgrades share the same icon on your map, so there is no way of knowing which is which until you collect them. Try to collect these before progressing into Meio's Tower. If you miss any, you can choose not to save your game so you may return to Kazakh to collect the ones you have missed. To see which energy upgrades you have collected, bring up your map and use / to scroll through to the status page. Scroll down to upgrades and it will show you the total collected against the total available.