British energy regulator Ofgem said it was allocating 24.4 billion pounds to fund the upgrading of the country's gas and electricity grid, adding 2 billion extra from initial plans announced in July.
Ofgem's proposals are part of plans to radically overhaul Britain's ageing energy infrastructure by 2020, as set out in its energy-security review Project Discovery.
Initial proposals made by the regulator, which has tried to curb energy company spending plans in order to provide value for the consumer, were slammed by the country's biggest energy distributor, National Grid, in July.
The company said in a separate statement on Monday that it would take time to review the updated proposals before deciding on whether they were acceptable or not.
Fast-rising consumer energy bills have caused anger in Britain among households squeezed by spiralling price rises and muted wage growth. A government advisory group said on Monday that a further 300,000 households risked 'fuel poverty' this winter.
Ofgem puts the cost of running and maintaining Britain's networks to 2021 at 38.2 billion pounds in total, meaning it has cut the total investment bill estimated by energy companies in their business plans by 16 percent.
"This provides a framework of strong incentives and penalties to stimulate the innovative and efficient operations of Britain's energy companies," Ofgem's chairman Lord Mogg said in a statement.
The regulator said its final plans earmarked up to 15.5 billion pounds to upgrade transmission networks for both gas and electricity, assets operated by National Grid.