NEW DELHI, Jan 19 (Reuters) - Rajasthan will need 4,400 megawatts of new coal-fired power capacity by 2036 to meet rising electricity demand despite India's top renewable energy–producing state adding more clean energy as it retires some ageing thermal plants, according to a government document.

The Central Electricity Authority, a think tank of the federal power ministry, has more than doubled its earlier estimates of 1,900 MW coal-fired power for Rajasthan, according to a letter dated November 27 that was addressed to the state power utility and reviewed by Reuters.

Rajasthan is preparing to retire its existing 1,350 MW old coal power projects, the document showed.

The Central Electricity Authority did not respond to a Reuters request for comment on the letter.

India, which meets about a third of its power demand through thermal projects, has set a 2070 net-zero goal, which includes more than doubling national renewable capacity to 500 gigawatts.

Power consumption in the South Asian nation is expected to rise as its economy expands, requiring a 40% increase in coal-fired capacity to more than 307 gigawatts by 2035, as per government data.

With the upwards revision in the state's coal-based power needs, Rajasthan's power regulator has decided to review its November decision denying a permit for a new 3,200 MW coal power plant, according to a document posted on the regulator's website.

The Rajasthan power utility had asked the regulator to review its decision, according to a separate document reviewed by Reuters.

The company said additional coal capacity was needed because solar and wind energy was not available round the clock and battery storage systems were not yet ready. The state gets about 70% of its power from renewable sources.