Nicola Sturgeon pledged that if the SNP are in power in an independent Scotland, the Government would remove levies for tackling fuel poverty and improving energy efficiency from people's bills.The levies would instead be directly funded by the Government.
The money an independent Scotland would receive from the European Union's emission trading scheme would at least partly cover the cost of it, according to the Nationalists.
This could cut energy bills for people in Scotland by 5%, or £70 a year, Ms Sturgeon said.
She announced the policy the day after British Gas, which operates in Scotland as Scottish Gas, said it was again raising prices, by 10.4% for electricity and 8.4% for gas, from next month.
Last week SSE said it will increase gas and electricity bills by up to 10% for millions of households.
Ms Sturgeon said the Scottish Government invests £80 million a year on energy efficiency schemes to help meet its climate change targets and on measures to reduce fuel bills under the Warm Home Discount scheme.
A further £120 million of funding comes from Westminster, with this funded by consumers through higher gas and electricity bills.
Speaking at the SNP annual conference in Perth, Ms Sturgeon pledged: "An SNP government in an independent Scotland will remove the cost of energy-saving measures and the Warm Home Discount from energy bills. We will provide the funding from central government resources.
"That will mean direct government funding for fuel poverty schemes of at least £200 million per year.
"This won't just allow us to deliver our energy efficiency schemes more effectively, it will also save hard-pressed consumers money."
This is "not just a short-term measure but a real and lasting cut in Scottish energy bills".
Further cash would be made available to help mitigate the impact of the so-called bedroom tax, she said.
This "despicable" change introduced by Westminster means housing benefit recipients deemed to have extra rooms lose some of their cash.
The SNP has already pledged to abolish it if Scotland leaves the UK following next September's independence referendum, while the Scottish Government has made £20 million available to mitigate its impact.
Today Ms Sturgeon, also the SNP deputy leader, pledged another £20 million for it in 2014-15.
"We won't stop demanding that the Tories repeal the bedroom tax, and we demand it again here today. This tax should go and it should go now. But if they refuse to do so, we will not stand by.
"We will allocate up to £20 million again next year so that we can continue this vital help for those hit by the despicable bedroom tax."
While such measures are "softening the impact" of the UK Government's policies, "only independence will allow us to chart a different course".
With Scots due to vote on whether or not to stay in the UK next year, Ms Sturgeon sought to contrast the policies of Westminster with those her party had brought in north of the border.
"Our Scottish Government has protected free education, frozen the council tax, put 1,000 more bobbies on the beat and we have secured free personal care for the elderly," she said.
"We've cut business rates and invested in new schools and hospitals. We've kept our NHS In public hands and we've done everything we can to protect the vulnerable."
She claimed that was "what good government looked like" as she went on to accuse Westminster of having "taken" North Sea oil revenues at the same time as it had "slashed" the Scottish budget.
"They've imposed the despicable bedroom tax," Ms Sturgeon continued
"They've widened the gap between rich and poor and sentenced 50,000 more Scottish children to a life of poverty with their welfare cuts. They've taken money from the disabled to give tax cuts to millionaires.
"And they've spent tens of billions of pounds on pointless and immoral weapons of mass destruction."
Her attack on the UK Government continued as she accused them of "destroying our social security system" saying their welfare reforms were "pulling the rug from the poorest and most vulnerable".
She also warned Westminster could "turn the screw" if Scots voted No to independence.
While pro-union politicians have held out the prospect of more powers for Scotland if it rejects independence, Ms Sturgeon claimed the "risks of a No vote are real".
She said there were MPs in all of the UK parties who were "itching" to abolish the Barnett formula, which determines how spending is distributed throughout the UK.
"Do not let anyone pull the wool over your eyes about the consequences of a No vote," the Deputy First Minister said.
"These consequences are real and they are clear.
"Scotland's social security system will be dismantled, Scotland's public services and universal benefits will be under threat. Scotland's budget will be cut."
She told the conference: "Scotland can't afford a No vote."
With less than a year to go till the historic referendum vote, she accused Prime Minister David Cameron of "running scared" of a televised debate against First Minister Alex Salmond.
Mr Cameron has repeatedly insisted the debate over Scotland's future should be conducted between politicians north of the border, pointing out that he will not be able to vote in the independence ballot.
But Ms Sturgeon said: "If he was at all confident in his argument, wouldn't David Cameron relish a debate with the First Minister. The Prime Minister says he will fight against independence with his head, heart, body and soul. So there you have it Scotland, it is only David Cameron's guts that are letting him down."
A Yes vote in the independence referendum is "not a vote for or against the SNP", she said.
"It is a vote for or against the power to take decisions in Scotland."
If the SNP is voted into power in an independent Scotland, it would return the Royal Mail back to public ownership, scrap the so-called bedroom tax and remove Trident nuclear weapons from Scotland, she said.
But the "opportunity of independence is not just about individual polices, it is about much, much more than that".
Leaving the UK offers Scotland the "chance to take responsibility and build a better society".
She told the conference: "We have a once-in-a-generation opportunity to chart a new course for our country.
"The choice we have been given is one of two futures: Scotland's future in Westminster's hands, or Scotland's future in Scotland's hands. That's what's at stake."