the New and Renewable Energy Ministry shows.
Hurdles remain for the likes of Tata, Shah said. For example, rules stipulating that India's 28 states must source a certain part of their energy from renewables have not been properly enforced. Electricity tariffs paid by states can also be too low for companies to make money.
Other investors have echoed Tata's concerns. Welspun Energy, which is eyeing $1.6 billion of new investments by 2017, told Reuters in October that land acquisition and poor transmission networks remained problematic.
JinkoSolar Holding, a China-based solar panel maker, told Reuters that low prices for solar products, cut-throat competition and high interest rates dragged on growth.
Shares of Tata Power were down 0.8 percent by 0956 GMT, versus a fall of one percent in the benchmark index.