India has decided to push ahead with a vastly ambitious plan to tap the power of the sun to generate clean electricity, and after a meeting chaired by the prime minister, Manmohan Singh, it wants rich nations to pay the bill.

Although India has virtually no solar power now, the plan envisages the country generating 20GW from sunlight by 2020. Global solar capacity is predicted to be 27GW by then, according to the International Energy Agency, meaning India expects to be producing 75% of this within just 10 years.

Four-hundred million Indians have no electricity and the solar power would help spark the country's development and end the power cuts that plague the nation. It would also, say some analysts, assuage international criticism that India is not doing enough to confront its carbon emissions. It is currently heavily reliant on highly polluting coal for power.

The plan provoked prolonged discussion at a meeting of the national climate change council in New Dehli yesterday, which resulted in major changes from early drafts. The draft document had envisaged a government subsidy of around $20bn (£11bn), and falling production costs, in order to achieve a long-term 2040 target of 200GW of solar power.

But experts pointed out that a large government subsidy contradicted the Indian government's stated position in the negotiations to agree a treaty to fight global warming. India, along with China and others, has demanded that the costs of clean technologies should be carried by developed nations, which have grown rich through their heavy use of fossil fuels.

Under the revised plan, India's solar mission will seek to achieve its targets by demanding technological and financial support from the developed nations. "In order to achieve its renewable energy targets, the Indian government expects international financing as well as technology at an affordable cost," said Leena Srivastava of the TERI energy research institute.

The move suggests New Delhi could use its solar energy plan as a bargaining chip at the forthcoming climate change summit in Copenhagen. The government reaffirmed its hardline position last month when the environment minister, Jairam Ramesh, told the visiting US secretary of state, Hillary Clinton: "There is simply no case for the pressure that we, who have been among the lowest emitters per capita, [have] to actually reduce emissions." If rich nations do fund the solar plan, the aim of both sides – economic growth for developing countries but with low-carbon emissions – will have been met.

Nonetheless, the plan's optimistic cost projections were debunked at the meeting, leaving it unclear how much money the 2020 target would need. "In terms of vision, it's a very good plan," said Kushal Singh Yadav of the Centre for Science and Environment. "But the nuts and bolts will remain uncertain until we get a fix on how much money is needed, and where it will come from."

Yadav pointed out that India has taken significant strides in wind energy production thanks to a shift in government policy.

Spain, for instance, added 3GW of solar power capacity in just one year in 2008.

In another significant policy shift following the meeting, solar thermal power (which heats water) will be given as much importance as photovoltaic (which generates electricity).

The Tamil Nadu government has already asked for New Delhi's assistance for setting up a 100MW solar thermal plant in the southern state.