Preventing the End-of-Life Residential Solar Photovoltaic and Battery Energy Storage System Waste Crisis: A Conceptual Model

Abstract

The exponential uptake of solar energy systems raises a concern on the looming waste problems once the panels and batteries reach the end-of-life. It was projected that residential solar panel waste will increase exponentially to 1,532 kT, whereas end-of-life battery energy storage will rise to 99.1 kT in 2050. An appropriate scheme to manage these waste streams is imperative to maintain the integrity of this green product as well as to reduce the environmental and human health impacts. This paper is an ongoing research employing a participatory systems modelling approach to conceptualise a causal loop diagram for end-of-life management of residential solar photovoltaic and battery energy storage in Australia. This approach is suitable for this topic as solar panel and battery storage supply chains are underpinned by a highly dynamic stakeholder landscape and characterised by non-linear system behaviours. This approach will enable a comprehensive understanding on the interrelationship and/or trade-offs between stakeholder’s roles and goals and revealing system behaviours over time. Stakeholder engagement throughout the modelling process is of importance to integrate different stakeholder perspectives and objectives; thus ensuring model validity. A systematic literature review was conducted a priori via the identification of drivers, barriers, and enablers from previous literature. An exploratory study was then conducted via an iterative expert review and a stakeholder survey. The iterative expert review process aims to evaluate the comprehensiveness, relevance, and clarity of the preliminary list of drivers, barriers, and enablers and to gather additional factors from experts. The validated list was then utilised in a stakeholder survey to quantity and compare the drivers, barriers, and enablers between different stakeholder groups. A wide range of stakeholders were engaged throughout the exploratory study process to ensure that different needs and objectives between stakeholders were captured. Based on the literature review and the exploratory study, the authors identified the key variables and their interrelationships in the system. In order to understand the feedback mechanisms in the end-of-life management system of residential solar photovoltaic and battery energy storage, a causal loop diagram and system archetypes were developed and validated via stakeholder workshops.

Keywords: solar panel, battery energy storage, recycling, circular economy, systems thinking