Diffusion is the phenomenon of how innovations spread from one adopter to others in a spatiotemporal domain, that is, over both space and time. To a degree, any breakthrough can be considered as innovative if it is construed as novel and new from the adopter's perspective. Diffusion research has existed for more than a century and the concept has been applied to apprehend and explains the spread of a wide variety of innovations. This article presents a brief history of diffusion research and notes the application of the concept to three specific research strands. The first strand is adopter perceptions on the characteristics of innovations and how perceived attributes affect the potential adopter's decision-making. The second focuses upon change agents and their locations, how change agents influence the decision process of potential adopters and why their locations matter. The last strand explains how adoption decisions are translated into spatiotemporal diffusion patterns.

How do innovations diffuse in societies and organizations? It is an interesting yet a complex question to answer. In order to shed some lights on this fundamental question, this book chapter provides the foundations of diffusion of innovations theory along with two empirical cases.

The theory is discussed through a three-component model of diffusion: innovation, sources and adopters. It mainly builds upon the seminal work of the well-known sociologist and communication scholar, Everett Rogers (1962).

The empirical cases are based on diffusion of solar photovoltaic (PV) systems. The first case is about off-grid solar PV systems in Bangladesh, while the second case is about on-grid solar PV systems in Germany.Overall, the differences and similarities between the two case studies in developing and developed countries let us explain how the characteristics of innovation, sources and adopters affect the diffusion of innovations.

Indonesia is facing challenges on the lack of electricity access in rural areas and the management of agricultural waste. The utilization of waste-to-energy technology can help in mitigating these issues. The aim of this paper is to assess the economic viability of a biomass gasification system for rural electrification by investigating its competitiveness in relation to various government supports. Financial modelling is applied to calculate Net Present Value (NPV), Internal Rate of Return (IRR), and Levelized Cost of Electricity (LCOE). NPV and IRR results indicate that biomass gasification is an economically viable option when appropriate financial government supports exist. LCOE result indicates that biomass gasification system is already more economically competitive compared to diesel generator even without additional support but it is less competitive compared to the national electricity grid tariff. In conclusion, the biomass gasification system is an economically viable option for rural electrification in Indonesian context.

Although photovoltaic (PV) systems have become much more competitive, the diffusion of PV systems still remains low in comparison to conventional energy sources. What are the current barriers hindering the diffusion of PV systems? In order to address this, we conducted an extensive and systematic literature review based on the Web of Science database. Our state-of-the-art review shows that, despite the rapid development and maturity of the technology during the past few years, the adoption of PV systems still faces several barriers. The wide adoption of PV systems—either as a substitute for other electricity power generation systems in urban areas or for rural electrification—is a challenging process. Our results show that the barriers are evident for both low- and high-income economies, encompassing four dimensions: sociotechnical, management, economic, and policy. Although the barriers vary across context, the lessons learned from one study can be valuable to others. The involvement of all stakeholders—adopters, local communities, firms, international organizations, financial institutions, and government—is crucial to foster the adoption.

This article discusses the determinants of technology diffusion among the low-income adopters, i.e. those belonging to the bottom of the pyramid market. Our aim is to analyse the variables that determine the adoption rate of Solar Home Systems. The analysis is drawn from a qualitative case study in Bangladesh based on interviews, observation and documents. We re-conceptualize diffusion process into three basic components: source, innovation and adopter. In particular, we focus on the characteristics of the source that are specific to the low-income market. In our case, the source is a social entrepreneur who seeks social wealth rather than economic wealth. Our empirical study may help to illuminate diffusion processes conducted by social entrepreneurs at the bottom of the pyramid because it contributes to a more comprehensive list of variables that affect the innovation adoption rate.

Despite the fact that diffusion research has existed for more than a century, a quantitative review covering this subject in a broad and general context is still lacking. This article reviews diffusion research by providing an extensive bibliometric and clustering analysis. In total, we identified thirteen clusters comprising 6,811 publications over the period of 2002–2011, and thereby describe the characteristics of diffusion research in an extensive and general way based on quantitative bibliometric methods. The analysis reveals that diffusion research is highly interdisciplinary in character, involving several disciplines from ethnology to economics, with many overlapping research trails. The concluding section indicates that diffusion research seems to be data driven and relies heavily on solely empirical studies. Consequently, influential publications rely on empirical data that support and change theories in modest ways only. In this contribution, we propose a review method that produces a fairly good overview of the research area and which can be applied to any knowledge field to replace or complement the traditional literature review.

With diffusion theory as the point of departure, this study analyses the factors that influence the adoption of renewable electricity from individual households’ perspectives. The analysis is based on a case study provided by a Swedish energy service company operating in rural Uganda. The company distributes electricity to rural households via a mini-grid powered by a biomass gasification system. Three critical dimensions are identified to be crucial for adoption: technical, economic, and social. First, there is an emphasis on the relative advantages of the new technology. Second, there are economic requirements regarding a viable financial system for adopters, especially in such a low-income market. Third, the social dimension is critical, particularly the importance of foreign firms collaborating with local actors. We further suggest that a lack of understanding of local communities can lead foreign companies to fail in diffusion attempts. While we focus on Uganda, the results of our research are highly relevant for foreign actors who attempt to penetrate rural markets in developing countries in general.

The needs for increasing energy access, the depletion of fossil fuels, and the urgency of climate change mitigation push the technology shift towards renewable energy sources. In Thailand, fossil fuels account for more than 90% of the energy mix in power generation. The government has established an incentive program to encourage the transition from fossil fuels to solar energy. However, there has been very little interest among household adopters to utilize this incentive. The aim of this study is to assess the economic viability of small-scale PV systems for on-grid household electricity generation in rural Thailand. The results reveal that the profitability varies greatly depending on system sizes, geographical areas, electricity consumption, and loan levels. Unfortunately, the current policy yields an economic loss for household adopters in various scenarios especially when the consumed electricity is deducted from the electricity generated from PV systems. Nevertheless, the competitiveness of PV systems can be increased with the provision of additional subsidy of which we recommend regressive subsidy rate. Our study emphasizes the importance of government intervention on the technology shift towards sustainable sources.

There are 1.3 billion people living without electricity, a large portion of which is in the bottom of the economic pyramid. Rural electrification via photovoltaic systems is one possible solution to alleviate their poverty. The aim of this article is to qualitatively investigate the potential for the transition towards off-grid photovoltaic systems. Two interrelated aspects are specifically investigated: photovoltaic system price and relative advantages for rural adopters. It has been shown that apart from the price, there are other advantages that can motivate rural inhabitants to adopt photovoltaic systems.