Iceland is a geologic freak which allows for geothermal energy generation. Even though it has this, the energy production isn't that great.
AFAIK, Iceland generates about 1336MW total capacity (calculated from CIA world factbook calculations). A modern nuclear power plant generates 1600MW.
A large aluminum smelter uses 1GW of power or even more (that is why they are often next to hydroelectric dams).
Also note that the EU emits about 70% of the Carbon dioxide that the US does.
Calculation:
Production per year kW hours 11710000000
Production per day (kWh) 32082191.78 Production per hour (kW) 1336757.991
MW: 1336.757991
They do use geothermal for home heating which has an above normal payout in large part due to the cold preventing normal heat pump's from working at reasonable efficiency and the long winders preventing solar home heating system from working when they are most needed them. Most of the continental US can use solar hot water heating systems with a fairly fast payback for lower cost than Iceland's geothermal systems.
I am just pointing out that "green" tech is already competing with fossil fuels and winning in many areas. It's not a question of turning off coal and other fossil fuels today, but rather limiting their use to the most useful systems such as cars and airplanes.
PS: Many homes in the US would reduce their CO2 emissions more by adding insulation than they would by doubling the fuel economy of their cars.
Many countries (such as Germany and some Eastern European countries) use natural gas in electricity generation in some places. This has lower carbon emissions, yet is substantially more expensive. It would also be interesting to consider CO2 imports and exports (if you buy a product that was manufactured in another country, then you import CO2). As an example, power hungry aluminium smelters are located where electricity is the cheapest. Yet everybody uses aluminium.
I would also like a citation for the “example, US's GDP is slightly less than the EU's but our CO2 emissions are double the EU.” statement.