In the late 1980s, the German-born chemist Michael Grätzel literally tied his name to an invention that is hailed as a  revolution in renewable energy .

To date, European consumers pay more for energy from renewables than for energy from conventional resources. One of the reasons is still the immaturity of the technology used for harnessing and distributing renewable energy.

Efforts to make buildings environmentally sustainable often focus on the technical side, such as energy efficiency. But there is more to sustainability than just energy efficiency.

“History will remember this day,” said Ban Ki-moon, secretary general of the United Nations, moments after the green-topped gavel, symbol of the Paris talks, was dropped on what is considered the most ambitious deal on climate change that the world has ever seen.

Turkey’s energy production for urban areas could be 100% based on renewables within 30 years if appropriate public policy is implemented.

Bioenergy represents two-thirds of the energy produced from renewable sources in Europe, though biomass sustainability is not taken for granted.

Traditionally our electricity grids were designed to move power from large nuclear and fossil fuel power plants to consumers, but renewable energy will see changes to allow smaller power generation from wind and solar to be hooked up to the grid.

Cooling and heating public buildings remains an expensive and a mostly unresolved issue in Europe. According to the not-for-profit think-tank Buildings Performance Institute Europe , Spain has about 11.

From thatched roofing in cold regions to reflective walls in hotter climates, for centuries buildings have been constructed with materials that maximize comfort within a given environment.

The European grid already faces transmission challenges, as the alternative current (AC) infrastructure has almost reached its transport capacity.

It may sound strange to anyone who lives in the vicinity of one or more wind turbines, but wind currently represents just  4.5-5% of the renewable energy supply in the world.