[Image above] Credit: NASA Goddard Space Flight Center; Flickr CC BY 2.0

The U.S. made significant strides when it came to cleaning up its energy act in 2015. In fact, the first quarter of 2015 alone saw $50 billion of renewable energy investments—up from $9 billion in 2004, according to a Scientific American article citing Bloomberg New Energy Finance.

As the U.S. teams up with other countries to uphold The Paris Agreement that was reached on Dec. 12, the investment in clean, renewable energy solutions will only increase in 2016 and beyond.

And materials science has been and will continue to be at the forefront of clean energy innovations. In 2015, we reported on three major clean energy trends thanks to advanced materials and engineering.

1. Solar cell efficiency

New solar cell design uses ‘invisible’ nanowires to harness power potential of reflected light—Scientists at Stanford University in California are developing a new solar cell that uses ‘invisible’ nanowires to redirect sunlight that is reflected away and lost with traditional solar cell designs.

New solar panel technology provides ‘clear’ cost-effective alternative to traditional photovoltaics—Engineers at Michigan State University say there’s a ‘clear’ alternative to existing photovoltaic technology that can be retrofit to existing glass-covered buildings—and it’s scalable.

First-of-its-kind ‘green’ antenna could double efficiency of solar cells—There might be a new solution in the works for improving solar cell efficiency. Researchers from the University of Connecticut have developed a “unique, ‘green’ antenna that could potentially double the efficiencies of certain kinds of solar cells,” according to a news release from the American Chemical Society.

2. Harnessing the power of wind energy

Iowa State University engineers put wind turbine towers made from precast concrete to the test—After almost a year of research and development, engineers at Iowa State University are putting their taller concrete wind turbine towers to the test with plans to revolutionize how we harness wind power in the U.S.

‘Slow wind’ power—a new way to think about energy efficiency—Wind energy is the fastest-growing source of electricity in the world, and harnessing it is one of the cleanest, most sustainable ways to generate energy. But, how windy does it really need to be to generate substantial power?

3. Smarter coatings for better cooling

Silica photonic crystal coating helps solar cells keep their cool under the hot sun—A trio of researchers from Stanford University in California has developed a clear and protective cooling coating for solar cells that allows them to shunt away excess heat and improve efficiency.

Keep your cool—New glass-based paint could take the heat off outdoor metal structures—A team of scientists from Johns Hopkins Applied Physics Laboratory in Maryland might have the solution for keeping metal outdoor structures cool in the hot sun—a new glass-based paint.

What major clean energy trends do you think 2016 will hold, and how will advanced materials and engineering innovations continue to change the game? Share your thoughts with us in the comments!