Projected costs of a grid-connected domestic PV system under different scenarios in Ireland, using measured data from a trial installation

This paper presents results of a study of projected costs for a grid-connected PV system for domestic application in Ireland. The study is based on results from a 1.72kWp PV system installed on a flat rooftop in Dublin, Ireland. During its first year of operation a total of 885.1kWh/kWp of electricity was generated with a performance ratio of 81.5%. The scenarios employed in this study consider: a range of capital costs; cost dynamics based on a PV module learning rate of 20±5%; projections for global annual installed PV capacity under an advanced and moderate market growth conditions; domestic electricity cost growth of 4.5% based on historic data; and a reduction of 25% or 50% in the CO₂ intensity of national electricity production by 2055. These scenarios are used to predict when system life cycle production costs fall to grid prices (grid parity).Average NPV and electricity generation costs ranged from -€14,330 and 0.58. €/kWh and were close to zero and 0.18. €/kWh for a system installed in 2009 and 2030, respectively. However, under optimistic conditions NPVs are positive for systems installed after 2021 and grid parity occurs in 2016. Findings are compared with similar international studies.