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UK LowCVP Launches ‘Technology Challenge’ to Accelerate Low Carbon Vehicle Innovation; Libralato Engines First Registrant

The first registrant in the Challenge is Libralato Engines, developer of a novel rotary engine (cutaway shown) promising a 5.5% gain in combustion efficiency and 50% reduction in NOx emissions. Click to enlarge.

The UK Low Carbon Vehicle Partnership is launching a Technology Challenge to provide a platform for promising innovations to be showcased to senior managers and directors of the component and vehicle manufacturers. The LowCVP is calling on UK innovators to submit creative concepts with the potential to cut emissions from road vehicles without the need for radical new infrastructure. The target of the Challenge is mainstream passenger cars producing less than 80 g CO2/km.

The LowCVP Technology Challenge is supported by the Institution of Mechanical Engineers (IMechE) and with an associated media partner, Cleantech Investor.

Market access and investment funding are key barriers for automotive technology companies. The Technology Challenge is designed to address these challenges by identifying the ten most promising innovations and who will receive assistance to progress their concept and in pitching this to an ‘Innovation Executive’, an audience of leading directors and technical experts from the automotive industry assembled by the LowCVP. A parallel activity will promote their investment potential.

The only entry criteria for innovations are that they reduce CO2 emissions from passenger cars; could be commercially deployed in 3–5 years; are on-vehicle, and; are compatible or could be easily integrated into the existing transport, energy and fuel infrastructures.

This could mean, as examples: advanced combustion concepts; emissions cleanup solutions; improved aerodynamics and flow control; new and advanced powertrains; energy recovery; lightweight materials and structures, or; optimized designs.

The best innovations will also be promoted by LowCVP via the Technology Challenge website with regular updates on the challenge featured in other LowCVP media.

The Technology Challenge culminates in an awards ceremony and dinner with colleagues from the low carbon vehicles sector. It is open for applications which will close on 7 September 2009.

Libralato Engines. One engine developer has already registered for the Challenge: Libralato Engines.

Libralato engine schematic. Source: Libralato Engines. Click to enlarge.

The Libralato engine is a rotary engine comprising two interlaced circular chambers of slightly different diameters. The Libralato engine has only four moving parts which perform the four phases in every revolution of the engine.

Inside the chambers revolve two rotors about separate center. The rotors do not rely on casing contact for their location as in Wankel engines. Sealing of the rotors against the chamber walls is excellent because of their circular orbits and due to the large rotor sealing surfaces, Libralato says. The engine does not require high manufacturing tolerances and wear of the rotors is not a mechanical constant.

Induction air enters at the center of the engine and compression/expansion occurs at the periphery producing uniform heat flow characteristics as air circulates around the two sides of the engine. The two rotors are connected together by a connection rod that has a quasi-circular orbit. Rotor 1, Rotor 2 and the connecting cam form the total internal mechanism of the engine. The Exhaust port is located on the outer side of the engine block.

The engine, according to the company, does not have a traditional Otto or Diesel cycle. There are two compression phases.

  • The first compression phase, which has a low compression ratio, controls the later scavenge of the exhaust gases. This scavenge phase has several functions. First, it helps to oxidize the exhaust gases more fully. Second, it reduces the temperature of the exhaust gases. Third, the scavenge air can be partially recirculated within the engine to act again in the induction phase, while the remainder of the air goes on to be compressed again in the second compression phase. Finally, it avoids an extra phase for the mechanical expiration of the exhaust gases.

  • In the second compression phase, the air is compressed at a higher compression ratio where the fuel is added. It is this fuel/air mixture that ignites to form the expansion phase. The inlet phase is in part contributed to by the scavenged gases. This all provides for an extremely efficient handling of the gases, according to Libralato, with a significant reduction of exhaust emissions and improved fuel economy.

Calculated comparative efficiencies. Source: Libralato. Click to enlarge.

The expansion volume of the Libralato engine is larger than the compression volume, allowing complete expansion of the gases (Atkinson Cycle), and optimizing the amount of chemical energy from the fuel to be converted into mechanical work. Thermodynamically, Libralato calculates that the engine will produce a 5.5% increase in efficiency over conventional 4-stroke piston engines.

The Libralato engine will function with any fuel; the company calculates that the engine can attain about 50% efficiency using diesel as a fuel.

Libralato Engines is seeking financial and industrial partners to help commercialize the engine.

Overview of the Libralato Engine.




Impressive! I've always been a fan of rotary engines for their simplicity and high specific power and, IMO, are the "final" solution for a PHEV range extender.

I'm only skeptical about the sealing claims.


The only entry criteria for innovations are that they reduce CO2 emissions from passenger cars; could be commercially deployed in 3–5 years; are on-vehicle, and; are compatible or could be easily integrated into the existing transport, energy and fuel infrastructures.

The upcoming Prius is rated in the EU at 89 g/km. The smaller hybrids promised by Toyota will probably achieve that 80 g/km. IIRC, the Lupo 3L was rated at 81 g/km.

What kind of breakthrough is this challenge actually trying to achieve?


Good design, effective scavenging without gasoline/air entering the oil filled crankcase can get the combustion chamber ready for the next cycle. I like rotary engines as well. I also like radials and cam radials. There is life in the internal combustion engine still.


Oh please no.
Not another wacko engine.

I had an early Mazda RX-7 and it was a great car and the engine was sweet.
You could enter an on ramp in second gear with plenty of power and not shift until 70+ mph, when the alarm said “that still-smooth whirr does not mean these RPMs are OK”
The basic engine concept was elegantly simple, however it was not light and had really bad emissions; the “smog pump” pushed air through a heater on the exhaust, an exhaust reactor, a catalytic converter and various valves to promote complete combustion and (try to) prevent backfires.
The exhaust system was as stout as an H2 tank for a fuel cell to contain the backfires.

It ended up quite complex – but simple compared to the Libralato

Roger Pham

This is a definite improvement over the Wankel that will solve many irritating problems of the Wankel. Still, the semi-wedge-shape combustion and expansion area may lead to slightly higher heat loss in comparison to a typical piston engine. On the other hand, friction loss may be lower than that of a piston engine.

According to Libralato literature, the claim to a calculated 5.5 points gain in thermal effficiency is due entirely to the Atkinson cycle, which a piston engine can accomplish as well.

I'm surprise that after 20 year, Mr. Libralato has not managed to produce a functional prototype that can give off real-life dyno reading of efficiency, instead of relying on calculated efficiency gain. Still, on paper, this is a promising engine concept that should result in a smoother and lighter-weight and lower-maintenance engine than the traditional 4-stroke piston engine.


This engine could be attractive for range extender for it's simplicity, fuel diversification option and probably maintenance free. For range extension efficiency doesn't matters. I agree with Roger Pham and have the same question - why still not existing working prototype?


I think efficiency matters for range extenders. The MYT engine has been dyno tested, but with air. They need to fire them up with CNG on the dyno to make me a believer though.

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