CASE STUDY: OFF-GRID LIGHTING Research Method
In order to gain a better understanding of the relation between SOI and PSS, we subsequently analyze specific sustainability effects within a case study research strategy. We conducted a single case study about OSRAM, a company providing off-grid lighting in Kenya. OSRAM is a company fully owned by Siemens AG, one of the largest multinational corporation based in Germany. Case study research is a strategy for the “systematic production of exemplars” (Flyvbjerg,
2006) . It does not follow a strategy of statistical sampling and thus the number of case studies is not a measure for the quality of this approach. Rather, even a single in-depth case study can contribute to theory (Flyvbjerg, 2006; Yin, 2003). We carefully considered trustworthiness criteria of credibility, transferability, dependability, and conformability (Lincoln and Guba, 1985; Shah and Corley, 2006) in our methodology, as will be further explained in the following paragraphs.
When selecting the case, we followed a strategy of extreme cases (Flyvbjerg, 2006), as this is one alley for a purposeful theoretical sampling and thus contributes the trustworthiness criteria of dependability (Shah and Corley, 2006). OSRAM provides a very unique approach for introducing a new PSS, embedding a highly innovative and sustainability-oriented technology. The example is also one of the flag ship programs within the area of Siemens’s corporate sustainability advances, and thus it is also well documented. Access to data was another reason for selecting the case (Yin, 2003).
With regard to data collection, we drew on multiple sources of data in order to analyze the case from multiple perspectives and, hence, to increase credibility (Shah and Corley, 2006; Yin,
2003) . Data collection covered public corporate reports and websites, documents from the public domain, and media reports. The documents were collected between 2009 and mid 2010 (Table 2). As we solely relied on secondary data from explicit documents and reports, risks with regard to data recording and management - as they are expressed in the trustworthiness criteria of conformability (Shah and Corley, 2006) - were reduced.
The data analysis can be considered abductive (Dubois & Gadde, 2002) relying both on an initial (deductive) conceptual framework (life-cycle; levels of innovation) and, at the same time, letting inductive findings emerge from the data. We used a content analysis to investigate the various documents presented earlier. The triangulation of data from different sources led to the emergence of the overall picture (Yin, 2003). In the sense of transferability (Shah and Corley, 2006), the research findings contain “thick” descriptions of empirical data related to the abductive categories, concepts, and overall structures. We further controlled the criteria of dependability by a critical audit of data: whereas the first author collected the first-order data (mere data) and proposed a first draft of the second-order findings (theorizing), the second author served as a critical reviewer of these processes.
The following findings section provides some background information on the case setting. Then the off-grid lighting PSS is presented and its effects on both the technological and overall PSS level analyzed.
Table 2. Data collection for case study