And it would review the structure of the electricity sector, with the possibility it might scrap the Electricity Commission.
The party says it would promote gas-fired power stations as a way of ensuring the lights stay on.
But National also says it would not expect any coal-fired power stations to be built under its proposed emissions trading scheme.
National leader John Key says his party would make security of supply its main focus if it leads the next Government.
While National would promote development of renewable energy projects, such as wind power, he says it also accepts gas thermal stations should be part of the mix.
So it would overturn a current ban by the Government on the building of new base-load thermal power stations.
Makes no sense says Greens
The Green Party says the National Party's energy policy released today makes no environmental or economic sense.
Its co-leader Jeanette Fitzsimons says using more gas-fired power stations rather than renewables would lead to higher electricity prices.
She says that's because gas is increasingly linked to the price of imported oil.