A Material Flow Analysis of Distributed Photovoltaic Application in Beijing with a Bottom-up Approach

As the problems of energy shortage and environmental pollution becoming increasingly serious, quite a lot of scholars have examined the feasibility of radical energy transformation, where all energy is provided by wind, water... [ view full abstract ]

As the problems of energy shortage and environmental pollution becoming increasingly serious, quite a lot of scholars have examined the feasibility of radical energy transformation, where all energy is provided by wind, water and solar power. The material basis which support energy transformation has also been widely discussed and predicted. Photovoltaic(PV) solar energy technology is being extensively applied, but most of the previous researches use the top-down estimation method to carry out the Material Flow Analysis and Life Cycle Environmental Impact Assessment of solar PV materials. However, the distributed PV application in China has not been adopted on a large scale. So, the top-down method used in calculating the proportion of PV market is somewhat subjective. Through our previous empirical study in a suburb community in Beijing, we have found that different types of users (industrial and residential users) have obvious difference in electricity consumption patterns in daily life and the acceptance of PV application.

Thus, this research starts with specific PV adoption decision makers, and takes the uncertainty of PV applications at the individual level into account: Will they choose distributed PV technology? Under what conditions (which determines the penetration of PV technology in the market) they will adopt? If they accept distributed PV power generation system, which type of technology will be selected? And how the MFA and LCA results change in different conditions?

This research investigates the main factors which influence users' acceptance and choice of distributed PV in a community level by means of household survey, and then constructs a selection model. According to this model, Agent-based Method is used to simulate the proportion of PV application in the whole city, up-scaled from the community level. Based on the results, material flow analysis and life cycle assessment are carried out, focusing on the rare metals and heavy metals in photovoltaic cells. In addition, according to the change of influencing factors in the selection model, we carry out different scenarios to observe the change of material flow.

The results show that the material flow analysis by bottom-up method is different with it by top-down method. By adjusting the renewable energy subsidies, reducing PV product costs or changing other factors can affect the flow of key metals.