Green-SÖP: The Socio-ecological Panel Survey: 2012–2016

1 Introduction

With a share of about 18% of final energy consumption (AGEB 2020) and 12% of direct CO₂ emissions (UBA 2020) in 2018, private households have a significant impact on the environment in Germany. At the same time, private households are a key target group for political interventions to combat climate change. Against this backdrop, policy has stipulated numerous actions to reduce energy consumption and to promote renewable energy technologies, such as CO₂-based automobile taxes and financial incentives for energy-related renovation measures (e.g. KfW support programmes). These political actions require careful evaluation of their effectiveness and cost-efficiency to avoid costly redundancies due to overlapping instruments.

Such an evaluation of environmental and energy policy measures requires a reliable database. Even though there are a few surveys that address environmental and energy-related attitudes, such data has not been available for private households in Germany. For instance, the German Environmental Survey, GerES V, which spans from 2014 to 2017 and is conducted by the Federal Environmental Office (Umweltbundesamt) and the Robert-Koch-Institute, focused on childrens’ health outcomes caused by environmental influences in current waves (cp. Schulz et al. 2017). In another survey, the Federal Environmental Office has elicited ecological awareness. It consists of repeated cross-sectional surveys and addresses various issues around consciousness regarding climate and environmental protection, consumption behavior and mobility (cp. Rubik et al. 2019). Furthermore, the RWI-German Residential Energy Consumption Survey (GRECS) is a nation-wide panel survey on the energy consumption, car use and living conditions of private households between 2005 and 2013 (cp. RWI/forsa 2015).

Owed to the lack of a data set that allows for an evaluation of environmental and energy policy measures, the Socio-Ecological Panel (Green-SÖP) was established in 2012. While it also collects some information on living conditions and energy use, its emphasis lies in the evaluation of behavior and opinions, the willingness to pay for energy goods and the perception of climate change. It is freely available to the scientific community. Based on this data, researchers can, for instance, conduct econometric analyses of various preference indicators and analyze the adaptation behavior of private households to climate change.

In the following section, we describe the data collection and structure of the Green-SÖP. Subsequently, we describe the socio-demographic characteristics of the survey sample and discuss its representativeness. Section 4 provides some examples of publications using the Green-SÖP data as well as further research possibilities to utilize the data set. Finally, Section 5 provides information on data access.

2 Data Collection

RWI – Leibniz Institute for Economic Research designed the surveys for wave 1–4 together with ZEW – Leibniz Centre for European Economic Research as part of the project “Evaluating Climate Mitigation and Adaptation Policies (Eval-MAP)” and for wave 5 jointly with Technical University Clausthal, University of Bremen and Helmut-Schmidt University Hamburg in the project “The social acceptance of the energy transition (AKZEPTANZ)”.

The first wave was collected in October and November 2012, the second in May and June 2013, the third in June 2014, the fourth in March and April 2015 and the current final wave was collected between December 2015 and February 2016. The Green-SÖP focuses on the risk assessment and perception of climate change, the adaptive behavior among German households and their willingness to pay for climate protection. Additionally, all survey waves contain information on socio-economic household characteristics, such as household size, place of residence, net household income as well as gender and age of the head of household.

The primary focus of wave 1 and 3 lies on the attitudes of private households toward climate change and their adaption behavior associated with leisure time activities, travelling as well as housing and insurance decisions. The questionnaires also include detailed questions on the perception of climate change, related expected losses and on experiences with natural disasters. Against this background, the third round in 2014 explicitly addresses the perception of flooding as a reflection of the experience of a severe flood in South and East Germany in the previous year.

The questions in wave 2 and 4 address the determinants of energy demand, the willingness to pay for different electricity mixes, precisely for pure green electricity, and the reaction of the energy demand on information and price signals. Wave 2 also contains questions on the influence of the nuclear disaster of Fukushima in 2011 on environmental attitudes. Wave 4 is supplemented with a discrete choice experiment on the role of energy label design in the purchase decision of a refrigerator (this part of the survey is available on special request at the FDZ Ruhr). The data of wave 2 and 4 allow the estimation of crucial determinants of private household energy demand, such as price and income elasticities through the connection to the energy consumption data (RWI-GRECS). Wave 5, stemming from a different research project but with similar topics of interests, includes more questions regarding the willingness to pay for the transition toward cleaner energy, such as accepting additional costs for the promotion of renewable energy.

An overview of the topics included in the Green-SÖP data set is given in Table 1. A full codebook is provided by Kussel and Larysch (2017) and Cordes et al. (2020) and the questionnaires are available on the FDZ Ruhr website. The surveys were conducted within the forsa household panel that nowadays consists of approximately 75,000 individuals in Germany, who are representative for the German population aged at least 14 years. The questions were asked to the household heads defined as the person who is responsible for the financial decisions within the household. The participants are usually familiar with surveys. Most households participated via an online questionnaire, while the households without an Internet connection received a device by forsa to take part offline. The participants gained bonus points which can be traded in for premiums. Table 2 reports the sample size in the five survey waves.

The Green-SÖP data set is connectable to other RWI data sets that rely on the forsa panel, particularly the RWI-GRECS (cp. RWI/forsa 2011, 2013, 2015). Moreover, we aim to connect additional surveys to the Green-SÖP data set, e.g. data collected in further projects on environmental topics within RWI.

3 Representativeness

In this chapter, we address the representativeness of the participants of the Green-SÖP sample in terms of regional and socio-economic characteristics with respect to the overall German population of household heads.^[1] The data for the number of German households stems from the official population projection based on the last census in 2011 (Federal Statistical Office 2020a). Table 3 contrasts the regional coverage of sample households with administrative data. The number of surveyed households is strongly balanced on the federal state (NUTS 2) level. This composition only slightly varies between the survey waves.

To characterize the distribution of the socio-economic characteristics, we use the data from the first and fourth wave (2012 and 2015) to contrast the figures over time. We compare their distribution with the figures from the 2011 census and its population projection (Federal Statistical Office 2020a, 2020b, 2020c, 2020d).

The surveyed households are represented by the household heads. The gender of the household head is predominantly male by two thirds of the responses. This is in line with the findings from census projection, as displayed in Table 4. Regarding household size, with 40% two-person households are most prevalent in the Green-SÖP. This group is, therefore, over-represented compared to the census projection, where single households represent the largest category (Figure 1).

Figure 1:

Share of people in the household.

Source: Federal Statistical Office (2020c), Green-SÖP (2016a2020b), own calculation and depiction.

This finding might be partly driven by the age structure of the survey households. The age of the interviewed household head varies from 18 to 91 years (in wave 4). The largest age group comprises household heads between 45 and 65 years, the so called “mature consumers” in market research (Figure 2). Compared to the German population of household heads from the census data, these groups are overrepresented.

Figure 2:

Share of age group.

Note: Household head in census = main income earner; in Green-SÖP = main financial decisions maker. Source: Federal Statistical Office (2020d), Green-SÖP (2016a2020b), own calculation and depiction.

4 Possibilities of the Dataset and Selected Publications

The survey has a special focus on the personal perception of and attitudes towards climate change. It captures the development of economic, environmental, and political opinions in Germany between 2012 and 2016. It also offers the possibility to characterize the households not only according to their socio-economic status but also to their risk and utility patterns in terms of environmental decisions and goods. Three publications, presented in the following, illustrate the variety of possibilities working with the Green-SÖP data set and how they enhance the political and scientific dialogue on the energy transition process in Germany. First, Andor et al. (2020) analyze information on private flood precaution strategies of homeowners and contrast respondents from flood exposed and non-exposed regions. They detect a charity hazard, a variant of moral hazard, as homeowners tend to rely on charity and governmental aid rather than installing precaution and buying insurances.

Second, Kussel (2018) exploits information on adaptive measures in the survey waves 2012 and 2014 and analyzes the adaptive behavior of households (e.g. air-conditioning, or green roofs) with respect to increasing temperatures. He finds that individuals who experience higher average summer temperatures are more likely to install cooling technologies.

Last, Andor et al. (2017) analyze the willingness-to-pay for renewable energy sources and its costs. They utilize questions from the second and fourth wave of the Green-SÖP. They detect a paradox that while the support for green energy developments increased between the two surveys, the willingness to pay for this type of energy decreased over time.

5 Data Access

The Green-SÖP data set is available as Scientific Use File at the research data centre Ruhr (FDZ Ruhr) at RWI – Leibniz-Institute for Economic Research. The data access is only given for scientific, non-commercial studies and granted to affiliated researchers of scientific institutions. It requires a signed data use agreement that can be applied for via the FDZ Ruhr website. The data can be obtained as a Stata^® dataset (.dta) file. The users are requested to cite the source correctly and to inform FDZ Ruhr about publications with the data.

When using the dataset Green-SÖP, please cite each wave separately as:

Wave 1: Frondel, M., C. Vance, M. Andor, G. Kussel, C.M. Schmidt et al. (2016), Socio-Ecological Panel. First Survey Wave. Green-SÖP. Version: 1. RWI – Leibniz-Institut für Wirtschaftsforschung. Datensatz. https://doi.org/10.7807/greensoep:en:v1

Wave 2: Frondel, M., C. Vance, M. Andor, G. Kussel, C.M. Schmidt et al. (2016), Socio-Ecological Panel. Second Survey Wave. Green-SÖP. Version: 1. RWI – Leibniz-Institut für Wirtschaftsforschung. Datensatz. https://doi.org/10.7807/greensoep:en:v2

Wave 3: Frondel, M., C. Vance, M. Andor, G. Kussel, C.M. Schmidt et al. (2016), Socio-Ecological Panel. Third Survey Wave. Green-SÖP. Version: 1. RWI – Leibniz-Institut für Wirtschaftsforschung. Datensatz. https://doi.org/10.7807/greensoep:en:v3

Wave 4: Frondel, M., C. Vance, M. Andor, C.M. Schmidt, G. Kussel, et al. (2020), Sozial-Ökologisches Panel, 4. Befragungswelle. Green-SÖP. Version: 1. RWI – Leibniz-Institut für Wirtschaftsforschung. Dataset. https://doi.org/10.7807/greensoep:en:v4

Wave 5: Frondel, M., S. Sommer, M. Andor,C. Vance, Technische Universität Clausthal et al. (2020), Socio-Ecological Panel, fifth Survey Wave. Green-SÖP. Version: 1. RWI – Leibniz Institute for Economic Research. Dataset. https://doi.org/10.7807/greensoep:en:v5

Furthermore, we recommend citing this data description.