[en] Energy generation and safety problems at the nuclear power plant have been analysed. Nuclear power plants are operated on the commercial basis in many countries today. Safety and security in energy generation and distribution is a complex problem. Energy supply reliability, security energy price and other issues should be co-ordinated and solved at the same time. Decentralisation and deregulation means new challenges for regulatory bodies and assurance of security. International co-operation in this field is very important. Western European Nuclear Regulators' Association (WENRA) consolidates efforts of regulatory bodies of European countries in order to harmonize approaches of nuclear safety. Nuclear Safety, and security of energy supply is the task and goal at the same time. (author)