Excel Watering Schedule

We are an Agriculture company and we're building a water management platform. One of the parts involve having an Excel file where I have to create a schedule for a farm manager that needs a way to program the watering week schedule. They work with a minimum time frame of 15 minutes. They also have different watering costs depending on the time of day and day of the week. Every Friday they have a total amount of water they intend to apply the following week. What they need is some way of dividing that total value for the 672 15-minute brackets along the week (4 15-minutes brackets per hour x 24hours x 7 days) taking into account the criteria of time of the day and day of the week. Preferably this would be all made inside excel. The costs are related to electricity price which depends on the time of day and day of the week. For example, at night and weekends, the prices are lower due to less demand for electricity. What I need is some way to insert the total amount of water I want to apply the following week, and automatically divide that value hierarquily, first only water in the cheapest periods and if not enough use other periods. They have several fields, each one with different maximum water capacity per hour. For example, I need to water 50mm for the entire week. However, it can only apply 0,5mm per hour. I have a table with each day of the week and the time divided in 15-minute timestamps (00:00; 00:15; 00:30, 00:45, 01:00: 01:15; etc) and it would need to fill each of this with the amount needed, following the given hierarchy of time price. Attached, is an example file of what the file looks like.