Now Portugal has raised the bar again, with renewable sources satisfying the country's total demand for electricity for an unbroken run of more than four days.
Events like these make positive headlines for green energy, and uncomfortable reading for the fossil-fuel extractors. But they also highlight the vast differences in achievement and ambition between European Union member states over their transition to clean energy.
EU differences, rather than their shared experiences and aims, have rather dominated the continent's internal debate in recent months - nowhere more so than the UK, which will be voting on whether to leave or remain in the EU on 23 June. Economic growth across the union has been weak at best and non-existent for many since the financial collapse of 2008, while national governments are bitterly divided on how to react to the refugee crisis prompted by conflict in the Middle East.
Nationalism, sometimes verging on xenophobia, does not provide the right mood music for the EU's member states to start getting serious about collaborating and sharing their renewable-energy resources and skills. We know that a large part of the answer lies in breaking down the energy borders - investing in the interconnectors and infrastructure that will allow wind, solar and hydro power to be distributed efficiently and economically across the continent.
This will be difficult to achieve when national leaders, not all them confined to the EU, prefer to build walls rather than knock them down.
While political will may be missing, as Portugal's renewables organisations' president acknowledges, at least public will seems to be growing for renewables - if media reporting is anything to go by.
When Spain set a new record in November 2009 by delivering more than 50% of its electricity from wind for five hours, media reports about the achievement were often followed by comments about the effect of wind turbines on the landscape. This year's successes were more likely to be accompanied by social media "likes" than questions about whether this is the way forward.
Likely to float
For the past five years Japan has been widely assumed as the most likely pioneer of utility-scale floating offshore wind. As the world's third-largest economy it has the industrial and technological muscle to drive rapid development and deployment, while in the wake of 2011's Fukushima disaster, the country's need for a greater proportion of clean, safe energy seems profoundly obvious.
Yet progress has been slow, with Japan seeming to be more interested in getting its nuclear industry turning again to replace its dependence on imported liquefied natural gas and coal, rather than looking for a more renewables-based solution.
Hawaii is now emerging as a more promising location for large-scale floating wind. It currently generates 90% of its electricity from imported fossil fuels, but has set itself an ambitious goal of achieving 100% of its energy from renewable sources by 2045. Offshore wind will be fundamental to the state hitting this target, and water depths of up to 800 metres compel the use of floating foundations. Now that the US has a domestic turbine manufacturer with a growing interest in offshore wind, and the bought-in hardware to exploit it, progress in Hawaii should be well worth watching.