A zero-energy refrigerator has been conceived that uses a gel-like substance to preserve and cool food, it has been revealed.The Bio Robot Refrigerator by product designer Yuriy Dmitriev is one of several shortlisted entries for Electroluxs Design Lab competition, Daily Tech reported.According to the news provider, the fridge design is four times smaller than a traditional refrigerator but maximises the available storage space by doing away with fridge doors.Instead, food items would be pressed into a green, biopolymer gel which closes in around them, suspending separate items in place. The gadget would not require a motor, compressor or any other electrical constituents, meaning that it would not use up any energy.Meanwhile, Genevieve Gorder, co-host and judge of HGTVs Design Star programme, told the Associated Press this week that homeowners can help to create a clean, uncluttered cooking space by installing a large white kitchen sink.