I have residential electricity consumption data for a $12-$month period in France. I need to design a battery system that can supply electricity for a residential user over a $3$ to $5-$year period. The design should focus on minimizing both peak time costs and overall production costs. I want to use a genetic algorithm to achieve these objectives. Can you provide a detailed approach, a flowchart, and the code for how to tackle this problem using a genetic algorithm to design the battery system and minimize costs effectively?