Building, living and energy(2003)
A building is a material structure intended to protect its inhabitants against the unstable weather conditions and to provide an optimum environment for a given activity.
The location of the building depends on its functions and relationships with other centres of activity and is a determining factor for the associated energy fluxes. The intermediary role the building plays between the changeable weather conditions outside and the appropriate indoor climate, together with other comfort functions (e.g. visual comfort, healthy air) determine the energy consumption of the building. An energy infrastructure ensures the energy supply of the buildings: natural gas, electricity, heating network.
The scattered living, working and recreational environment in Flanders has led to an enormous increase in the demand for transport and energy. The Flemish building tradition however has not been demonstrating much interest in energy-efficiency so far. Our preference for open-space planning, larger than average living accommodation and limited compactness, often in combination with insufficient thermal insulation explains our huge energy consumption, compared to the European norm. On top of that, the trend towards smaller families results in an increasing number of housing units.
The expected evolution of the population pyramid in the decades to come, with the higher age categories growing wider, will bring about structural changes in the human need for building, housing and recreation, on their turn having an indirect but broad impact on the energy consumption. Our growing dependence on fossil fuels, natural gas in particular, for both heat and electricity production for the residential sector increases the vulnerability of the families and is co-responsible for the large contribution of the building sector to the ecological problems and especially the emission of greenhouse gases.
The many dimensions of the issue ask for the development of a strong view, supported by both the users of the buildings and the professional industry. These views should take into consideration the life cycle of the investment decisions already taken in various sectors. As far as the scale and the type of energy fluxes are concerned, decisions on environmental planning affect our societies for several centuries, whereas decisions on the type of installations typically do so during a period of 20 years.
The environmental planning policy has to be oriented toward energy-efficiency, taking into account the actual reality, which is the result of changing views on culture and society. We should set high but realistic ambitions, without hoping that the current situation can be completely turned upside down. That means that first of all we have to start planning differently, that is to say condensing space and transforming functions, especially in suburban residential areas and post-industrial urban regions. Policy-makers have to bear in mind the continuous social evolutions and provide a framework encouraging group, duplex and ‘kangaroo’ housing. Finally, developing innovative forms of work organization should also have a positive effect on our energy efficiency (working from home, teleworking, satellite offices).
A gradual transformation of the energy infrastructure, from a centralistic towards a more distributed structure - having thought for security of supply - is advisable. This includes the use of local sources of energy and a diversification of the power supply and will also reduce the environmental impact.
To cut down on energy consumption for housing heating, it is key to design, construct and manage our buildings according to verifiable performance criteria. That is what the energy performance approach is aimed at. An energy performance policy with ambitious and clearly communicated objectives can reinforce a strong innovation of the building materials and systems market and be a strong incentive for the industry.
However, an energy performance regulation is limited to new estate and large-scale renovation programs and will therefore inherently have a rather slow impact: the renewal rate of the building park is approximately 1% per annum. Furthermore, this kind of policy only influences intrinsic building and installation factors, whereas the actual use of energy is also largely determined by the inhabitants’ behaviour. Since it will be a criterion in determining the market value when selling or letting a building, energy certification of buildings can also affect the energy performances of existing buildings. To avoid a fragmentary approach, the energy performance regulation will have to be backed up with supporting measures, having also consideration for materials use, local power generation, water consumption, indoor climate, implantation, communication, training, and social factors.