Earlier this month, Venrock and Oak Investment Partners invested $10 million in Phononic Devices’ thermoelectric approach to waste heat recovery.  But North Carolina-based Phononic isn’t the only waste heat startup that recently attracted new capital.

In late February, Dresser-Rand invested $10 million in Echogen Power Systems for a 20% stake in the Ohio company.  Based in Akron, Echogen (formerly known as reXorce Thermionics) is a 20-person, pre-revenue firm working to commercialize thermodynamic waste heat recovery systems that use supercritical carbon dioxide (ScCO2) as their working fluid.

“Supercritical CO2 has significant benefits in its energy density. It is a benign fluid that operates at high thermal efficiencies,” said Michael Persichilli, Echogen’s VP of Business Development, at the 2011 ARPA-E Summit. “We can provide a waste heat recovery system that takes up about 50% of the space of conventional systems at about a 30% lower capital cost and can operate over the lifecycle of a plant at less than four cents per kilowatt-hour on a levelized cost of electricity basis.”

For the past year, Echogen has been beta-testing its first demonstration unit, a 250kW system, with AEP at the utility’s facility outside Columbus, Ohio.  By the end of 2011, Echogen plans to have a much larger, commercial-ready system available.

“Waste heat [recovery] could be a huge market,” said Yanev Suissa of New Enterprise Associates.  “The problem is that you usually have to co-locate. If you are taking waste heat off of an electricity production facility, then you are fine, because you are tied to the grid.  In other applications, you…have to take into account the transmission, which usually makes it not economically viable. If you are co-locating, then how big is your market?”

Echogen is targeting large markets: power generation and large energy-intensive industries including steel, cement, glass, and pulp and paper.  

“When you are looking at waste heat, there is an interest if there is a very fast payback of less than two years when you are thinking of the stationary-furnace-type industries” said Paul Straub of Claremont Creek Ventures, an investor in thermoelectric waste heat recovery startup Alphabet Energy.  “If you are looking at longer paybacks, it is challenging to have someone sponsor what is a relatively large cap-ex project.”

According to Echogen, its system costs range from $2,000 to $2,500 per kilowatt of net power available, or $2 to $2.5 a watt -- far below the cost of traditional waste heat converters, but above the $1 a watt targeted by Alphabet Energy. (Alphabet grew in part out of research conducted at UC Berkeley by ARPA-E director Arun Majumdar.)

“Our payback depends on the offset cost of power,” said Persichilli.  “If you are looking at an average cost of power at six cents per kilowatt hour, the payback is approaching three years on a simple payback analysis without taking advantage of energy tax credits. If you are looking at a coastal state where the cost of power is 10 to12 cents, the payback is less than two years.”

Echogen claims LOIs with a multinational steel fabricator, a multinational glass company and a specialty products company, all of which have agreed to pilot projects in 2011 through 2012. 

“We are looking for strategic partners in other industries similar to the model that we have with Dresser-Rand,” said Persichilli.

Other waste heat recovery companies include established organic rankine cycle providers Ormat and UTC and startups Ener-G-Rotors, ElectraTherm and Recycled Energy Development (RED).

Should these startups join Phononic and target venture investors for their next financing rounds?  Or should they echo Echogen and focus on strategic investors?  Hard to tell.

“We are in a very odd time. [...] Strategic partnerships are actually leading financial investors to financing,” said Josh Green of Mohr Davidow Ventures. “Because of the large cash balance sheets that strategics have and [because] they understand the technology instantly, they are able to spend their money sooner. Then the financial types see that validation and endorsement and they come in behind.”

“We got the money [for Genomatica] from the strategics first and then VantagePoint came in seeing that validation.  Very unusual.  You don’t see it more than once a decade,” continued Green.  "We are going through a phase in clean technology where that validation is very important for startups.  Once we get into what a classic cleantech startup looks like, I think we will revert back.”


Yoni Cohen is a JD-MBA student at the Yale Law School and the Wharton School of the University of Pennsylvania.  A former college basketball writer for Fox Sports, he tweets about greentech @Cohen_Yoni.