The government has to ensure a wide-ranging supply of power in the UK or risk the lights going out, the energy secretary has told the Commons.
Ed Davey said it was impossible to "sit back and do nothing", as he outlined the government's Energy Bill at second reading on 19 December 2012.
The legislation aims to encourage more efficient use of energy in order to reduce the demand for electricity across the UK.
Mr Davey told MPs: "One of the reasons for this bill is the need to de-carbonise our electricity supply. It's a critical purpose.
"We need to move from coal to gas, from fossil fuels to low carbon, we need a more diversified energy mix with renewables, carbon capture and storage and new nuclear all playing their part, enhancing the security of electricity supply."
The energy secretary said the bill would protect consumers from price spikes in the fossil fuel markets, and attract billions of pounds of needed investment in nuclear power and renewables.
Labour tabled a "reasoned amendment" opposing the bill's second reading on the grounds it does not include "a clear target to decarbonise the power sector by 2030".
Shadow energy secretary Caroline Flint said this would be the "most cost effective way to meet our climate obligations" and "protect our economy and our consumers from volatile international gas prices".
It would also attract long term investment in jobs and industries, she argued.
Labour has also claimed that the bill fails to ensure the energy market is "properly regulated".
Ms Flint reiterated Labour's pledge to abolish energy regulator Ofgem, and replace it with a more effective body.
Conservative MP Tim Yeo, chair of the Energy and Climate Change Committee, accused the government of sending mixed messages on its green agenda.
"To secure investment at the lowest cost to consumers, absolute clarity of policy is needed.
"That clarity does not exist if different government departments put out different messages or worse if different messages emerge from DECC (the Department for Energy and Climate Change) itself," he said.
MPs voted on a Labour amendment to the bill which was rejected by 279 votes to 206, a majority of 73.
The Energy Bill was then passed at second reading. It now goes to committee stage for further scrutiny.