An offshore electric grid connecting Ireland and Britain is feasible within a decade at a likely cost of $8.7 billion, an EU-funded report contends.

Despite its costs, an offshore "Celtic supergrid" would result in economic growth, create jobs, push the development of renewable fuels and help achieve energy security, concluded the Irish-Scottish Links on Energy Study, which was released last week in Glasgow.

The feasibility study, backed by the European Regional Development Fund, said an "ambitious but achievable" goal would be to develop an undersea grid capable of transmitting 2.8 gigawatts of renewable generated electricity on a northern network stretching from Scotland to Northern Ireland.

A second, southern leg of the "ISLES" grid, hooking up Wales with Ireland, could handle 3.4 gigawatts, it concluded.

"No technological barriers" stand in the way of the idea, which would use high voltage direct current and voltage source conversion technology, the authors said.

The ISLES project, however, would require the navigation of complex cross-jurisdictional legal barriers and would be costly to implement, the study's authors warned.

The subsidies required to get it up and running -- likely to be borne by ratepayers -- work out to about $1.6 million per megawatt of offshore network capacity.

The plans are part of a larger-scale EU effort to develop a continent-wide supergrid that would allow for the import and export of electricity based on the fluctuating availability of renewable energy sources such as wind, solar and wave.

Scottish Secretary for Finance and Sustainable Growth John Swinney praised the study, calling it "further proof" of the "enormous economic opportunities renewable energy provides."

The ISLES study, he asserted, "shows that, by working together on a shared renewables grid, we could boost jobs, revenue and economic growth -- as well as helping secure future renewable energy supplies.

"These islands have some of the most abundant and powerful offshore renewable energy sources in Europe."

Northern Ireland Energy Minister Arlene Foster agreed, saying, "The ISLES concept study presents us with a realistic picture of an energy future where the regional wind, wave and tidal energy resources located far off our coasts are harnessed and used for our mutual good."

But she cautioned, "this will not happen quickly or easily," citing "significant challenges to government and potential investors" when it comes to working through issues of regional jurisdiction and the integration of local transmission grids.

Another concern, she said, is the need to avoid placing "undue costs on the end customer."

The offshore grid study comes shortly after British Energy Minister Charles Hendry called for greater cross-border cooperation between Britain and Ireland in the development of renewable energy.

"Movement toward a single European energy market presents a real opportunity for Ireland and the U.K. to achieve substantial revenue benefits from electricity exports," he said.

Big revenue boosts are indeed the prize for more cooperation between Ireland and Britain, agreed Scottish Energy Minister Fergus Ewing.

"I welcome Charles Hendry's comments, which acknowledge the importance of cross-border cooperation between Ireland and the U.K., and the huge revenue benefits it could bring.

"This underlines the case the Scottish government has been making about moving beyond national territories into a single European energy market and his comments demonstrate Scotland is plugged into an interconnected Europe."