This study examines the impact of solar energy's daily intermittency on electricity pricing, specifically investigating how the “duck curve” and “peak shifting” phenomena affect different consumer groups. Notably, commercial and industrial users exhibit higher demand around midday, while residential users' demand peaks during morning and evening hours. This disparity prompts a key question: do peak shifting and redistribution effects vary across consumer groups due to their distinct electricity consumption patterns? Our analysis focuses on Japan’s power system amid significant solar energy integration, particularly the effects on residential and commercial-industrial sectors, as solar capacity expanded from 42 GW in 2016 to 83 GW in 2022. Using monthly power consumption data, we uncover that increased solar penetration results in higher electricity prices for residential consumers and reduced costs for commercial-industrial users. A central finding is the mediating role of pumped hydro storage (PHS) stations in stabilizing prices during peak and off-peak periods by managing energy demand variability, thereby mitigating economic impacts across consumer groups. The study also sheds light on the issue of cross-class subsidization, where some groups bear disproportionately higher electricity costs due to renewable energy integration. This underscores the necessity for carefully crafted policy interventions to maintain market fairness and sustainability.