5 links have been added on this idea.
  1. Check out this car park umbrella that collects water and solar energy.
    https://indiaclimatedialogue.net/2018/06/01/upturned-umbrella-catches-sunshine-and-rain/

  2. There is a patent for a rainwater-collecting umbrella.

  3. Here’s a design concept for a rain-filtering umbrella.
    https://www.yankodesign.com/2020/08/24/this-minimalist-umbrella-purifies-and-stores-rainwater-in-its-shaft/

  4. Found these instructions for creating a water-harvesting umbrella with a filter from your ordinary umbrella.
    https://www.littleinventors.org/ideas/the-umbrella-filter/details