مفاعل صفر للطاقة التجريبي

Also known as Zero Energy Experimental Pile

thumb|right|NRX and ZEEP buildings, Chalk River Laboratories, 1945. The Ottawa River is behind the reactor buildings. The ZEEP (Zero Energy Experimental Pile) reactor was a nuclear reactor built at the Chalk River Laboratories near Chalk River, Ontario, Canada (which superseded the Montreal Laboratory for nuclear research in Canada). ZEEP first went critical at 15:45 on September 5, 1945. ZEEP was the first operational nuclear reactor outside the United States. == History == The reactor was designed by Canadian, British and French scientists as a part of an effort to produce plutonium for nuc