ARPA-E, the Department of Energy’s blue-sky research program, has handed out nearly $1.3 billion in grants in the past five years -- and it’s garnered nearly as much money from private-sector sources looking to move cutting-edge technologies from R&D to commercialization.

As of this week, companies backed by ARPA-E have secured more than $1.25 billion in private-sector follow-on funding, according to the latest tally coming out of this week’s ARPA-E Energy Innovation Summit outside Washington, D.C. That’s up from last year’s count of about $850 million in private-sector funding on grants of $1.1 billion, and about $625 million on grants of $900 million as of 2014.

Monday's announcement listed 45 companies, universities and research organizations that have won ARPA-E grants and received private investment. This doesn’t include companies that have held IPOs -- which includes Ceres in 2012, Ideal Power in 2013 and Arcadia Biosciences last year.  

We’ve been tracking a number of ARPA-E awardees over the years, with a focus on energy storage, renewable energy integration and grid-edge power electronics and software technologies. Here’s a quick tally of the significant funding events of the past year.

-  Transphorm, a startup developing gallium-arsenide (GaN) semiconductor technologies for more efficient power conversion, raised $70 million in June from KKR.

-  Smart Wires, a startup with power electronics technology that’s helping to direct power flows on transmission lines, raised $30.8 million in June from 3x5 Special Opportunity Fund.

-  Flow battery startup Primus Power raised $25 million in September from I2BF Global Ventures and subsidiary the Russia-Kazakhstan Nanotechnology Fund.

-  Varentec, a startup developing power electronics devices to manage voltage and power quality on low-voltage distribution grids, raised $13 million in December.

-  Fluidic Energy, a zinc-air battery company, revealed in November that it has raised more than $150 million from strategic, venture and government sources, and plans to deploy its systems in partnership with Caterpillar and Indonesia’s state-owned utility. 

-  24M Technologies, the A123 Systems spinout, unveiled details on its semi-solid lithium-ion battery technology in June, and noted that it had raised $50 million from Charles River Ventures, North Bridge Venture Partners, and strategic investors in Japan and Thailand.

-  1366 Technologies closed its $22.5 million C round in the spring of 2015 and announced it was building a 250-megawatt production line for its molten-silicon-to-multi-crystalline wafer technology in October.

Not all of the companies on ARPA-E’s money-raising list have made it, however. Infinia, a developer of Stirling engine systems for solar power, went bankrupt in 2013. Others are struggling to bring their technologies to commercial scale, such as compressed-air energy startup General Compression. And others have been bought up for uncertain returns on investment, as with Sun Catalytix’s acquisition by Lockheed Martin in 2014.