Range-extending gas/ethanol/methanol-Electric HybridWe are all well aware of Lotus Cars, but the Lotus umbrella also shades a motorsports group and an engineering consultancy that is responsible for handling the design/development of many systems or entire vehicle lines of cars, trucks, military vehicles, etc. that are marketed by myriad other companies without attribution. The engineering group recently invited me around to show off some of its recent accomplishments that are nearly ready for prime time. 
Remember the Lotus Evora 414E concept unveiled in Geneva in 2010? It was a Volt-like range-extending electric built to showcase a special piston engine Lotus Engineering has optimized for range-extender usage. That engine concept has grown into a family of gen-sets that are being put into production by Spanish Tier-1 supplier Fagor Ederlan Group which will in turn supply hybrid drivetrains for as yet undisclosed OE manufacturers for sale in Europe and North America by 2014.
The engines are intended only to drive a generator, never to be coupled to the wheels, so they can be engineered to operate at peak efficiency over a very narrow speed range. This obviates the need for pricey hardware like twin cams, four valves per cylinder, and variable control of the intake runner lengths and valve timing or lift, and because that speed is relatively low and constant (1500-3500 rpm), the rotating mass can be lightened considerably and under-square (76.0mm bore x 95.5mm stroke) cylinders can be employed for compact packaging. The design has evolved away from 414E’s integrated cylinder block/head/exhaust manifold setup (too difficult/costly to machine the valve seats), and toward a new design with an aluminum head that also incorporates the exhaust manifold.
The Range Extender Engine family includes an 866cc inline-2 laid flat, and an upright 1299cc inline-3. Each engine is available in both naturally aspirated and supercharged forms (using an inexpensive centrifugal supercharger). They’re all capable of being run on ethanol, methanol, or gasoline. Horsepower & pound-feet ratings for the engines running on gasoline step up from 31 & 49, to 44 & 69, to 51 & 79, to 74 & 111. The two cylinder measures 22 x 16 x 13 inches and weighs 132-165 pounds including the generator and inverter, while the three measures 20 x 17 x 24 inches and scales at 209-223 pounds. Officials hinted that the top spec engine may find its way into a Transit-Connect-style urban delivery van, while the two-bangers would likely be destined for A-class or mini-compact cars.
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