With President-Elect Donald Trump and his administration officially moving into the White House this Friday, the landscape of energy policy, investment, and incentives could see major changes in 2017. Given this backdrop, it seems like a good time to review some of the most important trends and policies concerning clean energy that we covered in 2016.

Here are 2016’s top 5 most popular blog posts at Energy Tech Matters:

1. New Solar Cell Device Surpasses Theoretically Predicted Efficiency Limit

A team of researchers at the Massachusetts Institute of Technology (MIT) built a working solar thermophotovoltaic device (STPV) that enables solar cells to break through a theoretically predicted ceiling on how much sunlight they can convert into electricity. This post describes how this revolutionary new technology can generate even more energy than theoretically determined by harnessing some of the solar panels’ waste.

2. “Holy Grail” of Renewable Energy Storage is Fast-Approaching

In 2009, the U.S. Department of Energy (DOE) created its Advanced Research Projects-Energy (ARPA-E) division to fund energy storage projects conducted by scientists at Harvard, MIT, Stanford, and the Lawrence Livermore and Oak Ridge labs. The DOE now believes that some of the 75 battery system projects it is currently funding have the ability to transform the renewable energy storage industry in as little as 5-10 years. This post overviews some of the battery technologies that are at or approaching grid-scale deployment.

3. Obama Administration Announces Plan to Promote Electric Vehicles

This post discusses the Obama administration’s collaboration with 50 federal and state agencies, electric utility companies, vehicle manufacturers, electric charging station companies, and others in the private sector to promote faster development of electric vehicle charging infrastructure and increased numbers of electric cars on the roads. The announcement, made in partnership with the Department of Energy (DOE), Department of Transportation (DOT), Environmental Protection Agency (EPA), Air Force and Army, came just after the DOE’s first-ever Sustainable Transportation Summit in July.

4. Massachusetts Legislature Passes Compromise Energy Bill

At the end of the legislative session in early August, the Massachusetts Legislature passed a compromise energy bill to significantly increase electricity produced by renewable energy sources. This post details the provisions of the legislation that require the state’s utilities to purchase power from on and offshore wind farms, as well as power from hydroelectric dams located largely in Canada. Governor Baker signed this bill into law a few days after its passage.

5. MIT Study Finds Energy Storage For Renewables Makes Economic Sense in Some Locations

A recent study by researchers at Massachusetts Institute of Technology (MIT) found economic advantages in combining large-scale energy storage systems with renewable energy projects, such as wind and solar farms, in some locations. This post includes details on the study, including the states examined and a comparison of the costs of different storage technologies.