Demography and Infrastructure

This chapter deals with the demographic and economic development in Germany and its federal states Hamburg and Mecklenburg-Western Pomerania between 2005 and 2030. It contains a common demographic-change framework and projection as input for all infrastructure models used or constructed within the InfraDem project. Germany is likely to experience ageing and shrinking of the population, but with large regional differences. For example, demographic change is expected to be exceptionally weak in Hamburg and particularly strong in Mecklenburg-Western Pomerania. The labour force is shrinking more strongly than the total population all over; it could even shrink in Hamburg, where the total population is still growing. The number of households is projected to increase and their size to decrease. Ageing is occurring within the smaller households; larger households (three and more members) stay young or are becoming even younger. The gross domestic product is expected to grow both in total and per capita, but at diminishing rates, and in regions with strong demographic change to a lesser extent.

Demographic transition impacts on economies in different interdependent ways. We have developed a macroeconomic overlapping-generations (OLG) model that respects a large set of these interactions and mechanisms of endogenous growth. The model is quantified for data on Germany. Simulations using the expected demographic transition in Germany reveal that alternative growth channels reduce the economic impact of the transition. These results are of special interest for private infrastructural investment.

As consumption patterns differ between households depending on the age and number of household members, demographic change alters the structure of overall consumption expenditure. This chapter presents an extended input–output model, which was used to study the impact of demographically induced changes in the structure of consumption expenditure on infrastructure use. The analysis is performed for the cases of Germany, Hamburg, and Mecklenburg-Western Pomerania. Selected sustainability indicators (energy use and emissions of CO₂ and NO_X) are quantified to study the implications for sustainable development. The results show that although the shift in consumption patterns tends to reduce energy use and emissions, it does not achieve the required decoupling of GDP growth and emissions.

Demographic change in Germany will lead to a remarkable change in the composition of the population, particularly in terms of the ageing of society with the prospect of a population decrease. These factors are the main determinants for future travel demand. This chapter describes the procedure of modelling transport for 2030 and illustrates the results with regard to the infrastructure. The findings of the Rostock Center serve as the main basis for the data in the transport model, belonging to the family of microscopic activity-based demand models. The future passenger transport demand will decrease in most areas. The workload of the road infrastructure will decrease correspondingly. Differences of the impact between the two demographic scenarios are low. Findings show significant spatial differences. The western part of Mecklenburg-Western Pomerania, for example, will experience some trip increases, but most of the regions will face a decrease in transport demand. Public transport in Mecklenburg-Western Pomerania will not gain any more passengers in the future. We therefore conclude that the planning process for infrastructure should include a proper approach that assesses the options of disassembling streets and restructuring them. Criteria for making this decision should not be the workload of the road, but rather accessibility questions. Future land use management will also play an important role.

In the following, we discuss the question of whether or not demographic change will have an impact on the infrastructure needed in the air transport sector. For this purpose, the population and economic scenarios for the year 2030, described in Chapter 2, are used as the basis to estimate the future German air transport demand. The consequences of demographic change on the passenger demand and its structure are discussed. For the airports of Hamburg and Rostock, the number of aircraft movements is derived from the estimated airport passenger demand. The current and planned infrastructure capacities at Hamburg and Rostock airports are compared with the predicted aircraft movements. The results show a significant change in the level and structure of air passenger demand. While the total population will decrease over the next few decades, it is expected that the specific demand (trips per capita) will rise. As a consequence, the total air transport demand will continue to grow. It is also estimated that the current high capacity utilisation at Hamburg Airport will further increase in spite of the capacity utilisation of Rostock Airport which will remain low.

A scenario analysis helps to determine the impact of an ageing and shrinking population on the energy sector in the context of pathways to sustainability. The scenario analysis in InfraDem follows the German “Lead Scenario” for the implementation of official targets for renewable energies and efficiency measures. This scenario points out an ambitious but realistic development towards a far more sustainable energy supply system by 2030 with long-term perspectives for a low-carbon energy system by 2050. The analysis takes into account the InfraDem population, GDP and household projections. The results show that demographic change will have a rather small impact on the national energy system compared to expected changes caused by political targets and strategies and the implementation of new energy technologies. The difference between the InfraDem high and low variant is between 3 and 4% for energy consumption and emissions. Although total population will decrease significantly until 2030, demographic change will tend to increase the residential power and heat demand due to an increasing floor space per capita and total household number as well as the higher specific energy demand of older people.

The German government intends to cover the demand for primary energy by 16% of renewable energy in Germany in the year 2020, and to reduce CO₂- emissions by 40% as opposed to the year 1990. One relevant CO₂ emitter is energy sector which has a big potential to achieve this target. On the other hand, the demographic change will strongly influence the heat supply system, a part of the heat sector. The following chapter analyses the challenges that arise by the decreasing heat demand due to demographic change and the need for a modified heat supply system based on renewable energies to attain the given target. This is done by a spatial analysis using Geographical Information System taking into account the actual and future heat demand, the existing infrastructure stock and the potential of renewable energy (mainly solar, biomass and geothermal). The analysis shows that the decreasing heat demand in general is a critical precondition for network-bound heat supply infrastructure and that renewable energies can help in selected regions to provide CO₂-neutral heat using existing or new district heat systems.

Over the last few decades, the number of elderly people in western European and other industrialised countries has been increasing. These demographic processes will continue. The growing share of elderly people in the population will lead to new challenges for ageing societies, particularly when the baby-boom generation retire. As a result, elderly people have become a focal point of interest in politics and science, and consequently in transport research. The purpose of this paper is to provide a comprehensive overview of empirical findings on the mobility behaviour of seniors – today, in the past and in the future – followed by a simulation of the future transport demand of seniors, taking into account their changing motorisation rates and travel behaviour. The article is divided in two main parts. The first part provides a systematic overview of existing empirical findings and outlines expected effects in the near future derived from these findings. In the second part, we estimate the future travel demand using the TAPAS simulation model (travel activity pattern simulation). This microscopic model allows us to see how the overall travel demand will change, particularly due to demographic change – in response to altered population structures on the one hand and altered levels of motorisation or modified behaviour in the group of elderly people on the other. The results allow us to separate the demographic effects from the effects caused by increasing motorisation and changing behaviour.

Demographic change affects the energy use in the household sector, which accounts for a major share of overall energy use. To understand this chain of effects better, we will devote this chapter to a more detailed analysis of households’ energy consumption. EVS data are used to identify differences in energy use between age groups, and the special roles of transport and space heating are discussed. We show that the effect of demographic change is not uniform across Germany: it depends on the technological and socio-economic conditions, which differ between regions.

The German national sustainability strategy and the federal spatial planning policy provide the basis for deriving a concept for sustainable development that corresponds to the object of study in the InfraDem project. Nine indicators of sustainability have been applied in the InfraDem project to evaluate the contribution made by demographic development to sustainable development. These indicators have been chosen according to the object of study. They are not applicable for the evaluation of overall sustainable development in Germany, Hamburg or Mecklenburg-Western Pomerania. This type of evaluation requires additional indicators, referring to factors such as research and development, habitation and the preservation of nature, which are not considered in this study. In order to achieve sustainable development, further measures – substitution and technological progress – as well as a change in behavioural patterns are required (for example, in the case of carbon dioxide emissions). A theoretical concept for the definition of sustainable spatial development, stipulating appropriate indicators and related target values, is required.

The following chapter summarises the key findings of the preceding chapters, embedding them into a discussion of general infrastructure policy. The resulting central question is how the burden of infrastructure adaptation associated with demographic change can be allocated. Inevitably, normative principles associated with regional infrastructures become the focal points, mainly culminating in the discussion on the equality of opportunity of welfare and the practice of regional redistribution policy. In this context, the implications for infrastructure planning and for sustainable development are discussed. Finally, the results, which are analysed with a focus on Germany, are reconsidered in terms of their relevance for other countries.