India, April 24 -- Spot electricity prices are fluctuating dramatically through the day, peaking at night when solar generation falls while sweltering evening temperatures drive demand for cooling. Prices at the Indian Energy Exchange have been rising to a maximum regulatory limit of Rs.10 per kilowatthour after sunset, before crashing to almost a tenth of that during the day, data on the firm's website show. The swing captures the plight of a grid flush with supplies during the day but starved at night, when 150GW of solar capacity switches off. The rapid growth in solar generation, along with the recent revival of coal, has majorly cut day-time shortfalls. Still, insufficient energy storage and the slow development of baseload sources, li...