Households in Northern Ireland will pay around £50 a year to meet the Government's renewable electricity target.

The Strategic Energy Framework proposes that 40% of electricity should be green by 2020, Enterprise Minister Arlene Foster added.

It reflects the need for effective action against climate change and securing sustainable supplies, the minister said.

"It is more difficult to forecast the impact of increased renewables on business consumers as it is harder to define the average business energy user, but clearly there will be increased costs from increasing the renewables contribution," she said.

"However, we should be aware that oil and gas prices are likely to increase in the future as demand continues to increase globally and stocks dwindle. So reducing our dependence on these fuels and increasing our use of renewables should help protect Northern Ireland consumers, across all sectors, from global price fluctuations."

DUP Assembly member Simon Hamilton asked the minister about the issue in the Assembly. The £50 estimate is half that of the original calculated cost.

The Executive has agreed to go out for consultation on the framework. Ms Foster's department is working with the Department for Social Development to consider how those in fuel poverty can be protected from price increases.

It will cost close to £1 billion to upgrade the all-Ireland electricity grid to cope with renewable energy and it may not be completed until 2020. Building a second north/south electricity interconnector would cost £160 million and would be recovered from usage charges over a 40-year period.

Natural gas storage in east Antrim will be dependent on confirmation of the geology in the area and private sector investment, with costs likely to be in the region of £200 million.

The consultation document said there will be benefits to Northern Ireland as a whole in terms of increased security of supply, economic development and carbon savings - taken together for a 40% target these are likely to give an annual benefit to Northern Ireland of approximately £50 million.