'I-tese newsletter Number 15 Spring 2012: an assessment of the 'phasing-out-nuclear cost' in France; Prospective: a posture in the service of man to help him in shaping the future; Climate in UNO: heading for a new multilateral agreement?; Electric mobility with fuel cell: which target price(s) for hydrogen at the pump? Does the 'real production cost' of the present electronuclear fleet exist?

Based on the definition of two scenarios (a reference scenario with a steady power, and phasing out nuclear), a first article discusses the assessment of the cost of phasing out nuclear for France. A second article comments the importance given to prospective studies which more particularly emerged in the United States after World War II. This article is followed by another one which addresses the peculiar case of energetic prospective studies which can be perceived as a battle of scenarios. An article discusses the need of a new agreement on climate after the Durban conference. The next article discusses how to characterize the competitiveness of hydrogen used in fuel cells in the transport sector. Then, an author comments a report by the French Revenue Court about the initial investment costs of the electronuclear fleet, present operation expenses, maintenance costs and provisions for future expenses