"During every election, political parties promise free power... People need to think about these promises," said Modi at a renewable energy conference in New Delhi.
The parties make these promises in such states which rely on electricity supply from other states, he added.
"Water accounts for a major chunk of the input cost of farmers. The cost of water is basically due to cost of power.
We have to understand the problems farmers are facing," said Modi.
Arvind Kejriwal-led AAP trounced the BJP in Delhi assembly polls. The party in its election manifesto had promised to cut electricity bills by half among other freebies.
Delhi has a power demand of about 5,000 MW and is largely dependent on other states to meet its requirements.
Reacting to Modi's apparent dig at AAP, senior party leader and AAP's Delhi Convenor Ashutosh urged the prime minister to help the state government to make power affordable.
"I don't want to make any adverse comment on the Prime Minister. I just want to make a request to him on behalf of the party that he should help us to make electricity
AAP leader Ashish Khetan, who played a crucial role in chalking out party's agenda to solve the power problem in the national capital, said the previous governments neither promoted solar energy nor did they have any good policy of any alternate source of energy.
"When coal-based energy is concerned we have to depend on states like Chattisgarh, Jharkhand among others. Secondly, power plants of the country, though may be located in other states they produce electricity for the whole country.
"Reducing power tariff and bringing in reforms in the power sector is a different issue and linking it to power production is quite weird," he said.
The Congress slammed Modi saying there is a huge gap between what the prime minister preaches and practises.
"He should look within. The prime minister should direct that question to (Punjab chief minister) Sardar Prakash Singh Badal to whom they gave a Padma Vibhushan. Because after all the Akalis have been the pioneers of politics of free power.
"Even as we speak there is an Akali-BJP government in Punjab and power to the farmers is free. So, is PM Narendra Modi going to advice the BJP in Punjab to take it up with the Akali Dal or in the Cabinet that power tariff should be imposed on Punjab farmers," senior Congress leader Manish Tewari said.
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