A mechatronics engineer works to automate the transfer of materials and goods, and the manufacturing process. Their tasks involve identifying areas for task automation, designing, developing and testing potential mechatronic devices, and implementing design solutions.
A typical tea bag has somewhere between a gram and two grams of stuff in it. If the entire contents were nothing but fructose, and that fructose completely dissolved when you made your tea, you'd consume between 4 and 8 calories (carbohydrates contain 4 calories per gram) per cup of tea -- so that's the ceiling.
These smaller pieces are more prone to oxidation and turning stale. Your best bet is to buy tea bags in quantities that you think you can use up within six months, so that the flavor and aroma remain strong, and before it becomes a bit more stale after one year. Add a note to the container holding the stored teabags when you bring them home, so you know how long to keep them.