Smart City Block: a new level of intervention for city renovation and reducing energy consumption

The Directive 2002/91/CE on the energy performance of buildings requires that by end 2020, all new buildings within Member States are “nearly zero-energy”. Though this is technically feasible for any new construction, the problem of reducing the energy consumption of the existing building stock seems much trickier. Can or will all owners invest to renovate their houses? Are information and financial incentives sufficient? Will individual cost-benefits or return on investment calculation at micro level be enough to overcome the barriers to renovation?The Smart City Block project aims to promote renovation at the level of a city block. It thus directly tackles the insufficiently explored “meso level” where stakeholders with different motivations should interact to achieve a common goal. This interdisciplinary project proposes a variety of technical solutions including insulation techniques and highly energy-efficient equipment but also exploits energy savings that can only be achieved by behavioural changes related to new living organisations. As the proposed approach cannot be applied systematically to any city block, the first step was to develop a methodology for determining where such a block renovation is feasible, within the 5000 city blocks of Brussels.In order to evaluate the acceptance of households, a survey was conducted on four city blocks in Brussels, representing over 450 households. It was therefore necessary to expose the possible solutions in a comprehensive manner for a diverse set of inhabitants. A list of “elements” (including items such as architectural, building performance, HVAC, common living spaces, equipment and gardens or vegetable garden) was produced by specialists (engineers, architects, urban developers and sociologists). The last section of the paper provides the survey methodology and some early results showing inhabitants low attractiveness of energy saving technologies and limited desire to share energy consuming activities.