Worker Energy is a former system used in Restaurant City to allow employees to work. The more energy they had the faster the worked, but working made their energy decrease.
A full energy employee was able to work during 4 hours (3 hours before the '4 hour update'). Employees couldn't work without energy, but there were two ways of getting energy back: food and rest.
Players could feed employees with 4 different foods, giving respectively 25%, 50%, 75% and 100% of the maximum energy amount. Prices differed according to the energy given by each food. Food was also available as free gifts.
Players could also choose to let employees resting. Employees recovered about 5 seconds worth of energy per second when resting. This option was free but employees disappeared from the restaurant while resting and didn't work. As a consequence, it was a good option when running low on cash, but feeding employees allowed to get more profits.