The web page could do with more structured approach because I can't see which one describes the engine architecture. So I used Mr. Google and found:
http://www.greencarcongress.com/2016/07/20160721-aquarius.html
PSA Groupe is evaluating a free-piston engine linear-generator under development by Israel-based start-up
Aquarius Engines for use as a range-extender in its electric vehicles.
Accordingto a report from Reuters, PSA Research and Development Director Gilles Le Borgne said that while the company is evaluating the technology, “Nothing has been decided yet.” According to Aquarius, several prototype vehicles using its free-piston generator will be road-tested by 2017.
A number of groups have recently or are currently investigating the use of free piston engine power generation applications with a focus on automotive, including academic work at West Virginia University (WVU), Sandia National Laboratory (SNL), Chalmers University of Technology (Sweden), and Shanghai Jiaotong University. (
Earlier post.)
. . .
Another approach:
https://en.wikipedia.org/wiki/Achates_Power
Achates Power is an American developer of opposed-piston, two-stroke, compression ignition engines for use in commercial and passenger vehicles. Based in San Diego, California, the company was founded in 2004 by James Lemke.
According to Achates Power, its opposed-piston, two-stroke engine has demonstrated an increase in fuel efficiency and similar engine-out emissions levels[1][2] when compared to the Ford Power Stroke engine, named one of the leading medium-duty diesel engines.[3] More recently, the company published a technical paper citing a 30 percent fuel economy improvement when its engine was benchmarked against a next-generation diesel engine equipped with advanced technologies.[4] The paper also highlighted the Achates Power engine's potential to meet Tier 3/LEV III emissions and 2025 CAFE.
Achates reports high thermal dynamic efficiency and I find it credible because there is no valve train. The free piston engine should also have similar efficiency for the same reason. I notice that a Wankel engine is being tested for range extender which means it can be tuned for high efficiency and low emissions.
I drive a 2014 BMW i3-REx with a 34 hp (25 kW) range extender that uses a repurposed, 640 cc, motorcycle engine. Higher efficiency would move my highway MPG from 40 -> 45 MPG. I have plans for cooled, exhaust induction that should reduce throttle losses and boost MPG.
As for Aquarius and Achates, they have patents and are trying to sell the idea to existing car makers. IMHO, this is unlikely to work. A better approach would be to find a 'glider' source and build out their own plug-in system. The other alternative, make a retro-kit for existing EVs:
- Leaf - there are a lot of them
- Bolt - more modern (and GM engineering needs shaming)
Offer an after market, range extender solution; go through the EPA/CARB emissions testing ($500,000), and; sell the conversion kits.
Bob Wilson