Not all power requirements are the same and we know this very well.  That is why we have created a solution that can separate out the essential requirements and ensure that they have sufficient power throughout the day, while the other requirements will only run when there is Grid Power.  This will allow for us to size a smaller battery bank that caters only to the requirements that need 24 X 7 power, hence bringing down the capital cost and the payback period.  As an example we can have only the refrigerators (storing medicines and vaccines) and incubators get 24 X 7 power in a PHU, thus requiring a smaller battery.