* Devil is in detail of implementing broad goals
* National plans should complement regional plans
* European Commission seeks national plans by mid-2017 -document (Adds quotes from German economy minister)
By Barbara Lewis
LUXEMBOURG, June 8 (Reuters) - European energy ministers on Monday signed three accords on closer power and gas ties but differences remained over implementing a single energy market and 2030 green fuel goals.
The European Commission, the European Union executive, has used the political crisis with the bloc's biggest energy supplier, Russia, to focus on creating an energy union through rationalised connections across its 28-members to share fuel and curb the need for imports.
The grand plan is also meant to harness efforts to lower carbon emissions as France readies to host United Nations climate talks late this year.
At a meeting of energy ministers in Luxembourg on Monday, a group of countries, including Germany and the Benelux nations, signed two declarations on security of supply. Baltic nations, among the most dependent on Russian gas, signed an outline accord on closer EU energy links.
"The signatory countries are determined to enhance security of supply through further market integration," Climate and Energy Commissioner Miguel Arias Canete said. "This is one of the main building blocks of the energy union."
Germany is among those keenest for market integration as it struggles to absorb intermittent wind and solar power as part of its Energiewende, or transition away from fossil fuels.
"It means, for the first time, that Germany is not only looking at the Energiewende on a national level," Sigmar Gabriel, Germany's economy minister, told reporters, at the signing ceremony.
Declarations are easy compared with the detail of implementing them.
The EU last October reached an outline deal on three 2030 targets to cut emissions by at least 40 percent versus 1990, improve energy savings to at least 27 percent and to increase the share of renewable energy to 27 percent.
The goals replace three 2020 targets, all of 20 percent, which the bloc is close to achieving.
But member states, such as sceptical Britain, jealously guard their right to decide what kind of energy they use, making it difficult to agree the detail of implementing policy goals.
An internal Commission note, seen by Reuters, acknowledges the need to preserve member states' right "to define policies matching national preferences and circumstances" but says national energy plans must complement regional plans and vice versa.
To allow each country to present its plan and others to comment, it proposes to hold forums next year, after which draft plans should be submitted to the Commission by mid 2017. (Additional reporting by Tom Koerkemeier; Editing by Jason Neely and William Hardy)