Tender rig

Tender Assisted rigs are an existing type of development drilling, workover or plug & abandonment rig (same "Familly" as Jack Up, Semi submersible or drillship). It is however the only design that can operate in both Shallow and Deepwater (from 20m to 2,000meters) . 
It is recognized in the industry as one of the most efficient and economical type of rig for development, work over or Plug&Abandonment (P&A). 
They are composed of a tender vessel (specially designed support vessel) and a self contained drilling rigs. The tender vessel are typically equipped with storage facilities (bulk, mud, tubular,spare parts, Consumable), living quarters (120 to 200 pax), power generation facilities, cranes, and helideck. Tender vessel are typically flat bottom barges or semi-submersible however in some instance, it was used a jackup- or semi-submersible rig or liftboat .