· · · Institutional Repository

Computer simulations are increasingly used to study the development, adoption, and evolution of technologies. However, existing models suffer from various drawbacks that may not be easily corrected, among them lack of internal structure in technologies, static environments and practical difficulties of introducing rational or semi-rational search for solutions. This paper discusses the theoretical background and rationale for an improved model, the Adder, and sketches out the model's main features. As an example of the model?s flexibility, we use it to provide insight into why uncertainty about performance of technologies and user needs may be an essential component in the evolution of technology.

Julia Kasmire is writing her PhD dissertation on technology transitions in the Westland greenhouse area. She is looking whether Universal Darwinism (UD) can explain these processes and could lead to could policy recommendations. As a prelude to her research this report focuses on, the less ground braking, technology diffusion in the Westland greenhouse area. UD is not taking as a point of departure to be able test without prejudice whether the concept holds. In this report an answer is given to the following main research question: How does a technology diffuse through a network of greenhouse farmers in the Westland and which factors are important to this process? This is done by answering three sub questions. The first sub question is the following: What methodological individualistic framework on technology diffusion in the Westland can be developed? To answer this question first an overview is given of the literature on technology diffusion from which a preliminary framework is constructed. Central in this framework are the decision individual greenhouse farmers make. Based on their own characteristics, the characteristics of the environment and the available information on the characteristics of technologies decisions are made. This framework has been taken as a point of departure for an interview with a greenhouse farmer and subsequently questionnaires were sent to other greenhouse farmers. After this the framework was enriched with the information retrieved from the interview and the questionnaires. Important results were the fact that greenhouse farmers may be considered boundedly rational, that they value information from peers quite high and that an innovativeness/risk attitude is a differentiating characteristic. How can technology diffusion in the Westland be modeled? For the second research question an Agent Based Model (ABM) was developed. The model combines the physical and social layers of technology adoption. In the physical layer technologies are acquired and used as well as products are sold. In the social layer agents communicate about their satisfaction of their currently owned technologies. Because the agents are heterogeneous and they can only communicate about sets of technologies (not the individual benefit of one technology), they send limited information. Depending on the characteristics of the technologies the model behavior may result in technology diffusion. This has been discussed when answering the last research question: Which factors are important to technology diffusion in the Westland? Four experiments with the ABM have been performed and discussed. The first two experiments show that, at standard settings, technology diffusion does occur for technologies that are beneficial for all companies. The second experiment shows that having a high percentage of innovators (10-20%) is slowing diffusion down at first but leads to higher diffusion rates in the long run. Valuing the opinion of peers highly leads to high diffusion rates in the short run but is not the best strategy in the long (when self obtained knowledge is the most valuable). The fourth experiment shows that talking to many peers is beneficial for overall diffusion but that this effect diminishes with an increasing number of peers with who is communicated. A general important conclusion for the third sub question is that time is a very important variable in technology diffusion. The characteristics of the greenhouse farmers have different effects at different times and this research cannot tell at which point in time one should look exactly.

Horticulture, a pillar of the Dutch economy, has already achieved remarkable productivity increases through the use of natural gas for heating, lighting and CO2. Further innovative technologies that could aid the transition toward sustainable energy use, including heat/cold storage and deepgeothermal heat sources, are currently in development and spreading. However, there is a need to better understand the processes of technology diffusion in this industrial cluster to help stakeholders retain their competitive advantage and establish the best way to influence the energy future in the region and in the sector. This presentation discusses the experimental results of a series of agent based models of the greenhouse horticulture sector in the Netherlands, simulating the technological innovation decisions of greenhouse growers. Surveys of greenhouse growers suggest that innovation decisions are made on the basis of personal experience and information shared from other growers. In the model, each greenhouse grower must learn how to operate a greenhouse by evaluating their repertoire of technologies, exchanging information with other growers about their technological evaluations and purchasing new technologies to augment, expand or replace the existing selection. The interactions of greenhouse growers and the flow of information between them lead to emergent patterns, including diversity, adaption and complexity, in the diffusion of technologies throughout the community. These emergent patterns of diffusion indicate that technological innovations develop and spread according to evolutionary mechanisms, suggesting that influencing, supporting or advocating the diffusion of sustainable technologies in this sector must also follow evolutionary mechanisms. As an evolving system, the reality of technology, innovation and transitions may require new approaches to management that work with, rather than against, the properties of evolving systems. Survey results, horticulture cluster background, model design and simulation results will be presented and implications for regional industrial management are discussed.