With India’s soaring energy demand and inadequate access to grid electricity in rural areas, off-grid solar power is a potential alternative for tackling India’s energy poverty and inequality. However, little knowledge exists on: (1) the spatio-temporal pattern of solar power adoption by the residential sector in rural areas of India, (2) the extent to which solar power has alleviated (a) energy poverty, and (b) energy access inequality. Using panel data from approximately 9000 rural residents in six energy-poor Indian states, we compare the solar power adoption rate across states over time (2015 and 2018), examine the contribution of solar power for alleviating energy poverty, and identify socio-economic characteristics of adopters. The average solar energy adoption rate was nine percent in 2018, five percentage points higher than in 2015, with the highest adoption rate in Bihar, followed by Uttar Pradesh and Odisha. This growth was driven primarily by solar lantern uptake, with the use of solar home systems only growing by less than one percentage point. Solar energy adoption significantly contributed to energy poverty alleviation but was limited to improving illumination. Solar home system adoption improved the use of electronic appliances among adopters but did not significantly increase radio/television use. Solar power played a limited role in energy inequality alleviation. Lower caste, poor households, and day laborers are less likely to adopt solar power and less aware of the availability of solar power as a residential energy source than higher caste, non-poor households, and self-employed farmers, traders, and salaried employees.