Reusable Cups Here at npower we are always looking for ways in which we can reduce our environmental impact. A particular concern is the use of paper coffee cups in our offices, so we’ve worked with Baxter Storey to ensure our people can now use their own reusable cups. If you wish to use your own cup, in order for it to be permitted for use it must tick the following boxes: 3 Clean At least 12 fluid ounces (341ml) Secure lid 3 3 If your cup doesn’t fit the criteria we will ask you not to use it.