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HyBoost demonstrator debuts at LCV2011; 50% by swept volume downsizing with low-cost electrification

HyBoost demonstrator. Click to enlarge.

The HyBoost project vehicle was revealed for the first time today at the Cenex Low Carbon Vehicle 2011 event hosted at Rockingham, UK, demonstrating a combination of high-impact, low-cost electrical systems which offer the prospect of radical engine downsizing using electric supercharger and energy capture and storage technologies within an otherwise conventional gasoline powertrain architecture. (Earlier post.)

The HyBoost project has been led by Ricardo in partnership with Controlled Power Technologies, the European Advanced Lead Acid Battery Consortium, Ford, Imperial College London, and Valeo, with co-funding from the UK government-backed Technology Strategy Board.

Together the partners have sought to demonstrate an extremely cost-effective, ultra-efficient gasoline engine in a C-segment passenger car delivering the performance of a baseline 2.0-liter model but with significantly reduced real-world and drive cycle CO2 emissions, and comparable improvements in fuel-economy.

The project deliberately focused upon technologies and systems that are already on the market or are capable of practical production implementation in the near term. Particular focus was placed upon sustainability, avoiding the use of scarce or expensive materials, providing the straightforward manufacturing processes, and offering the high levels of scalability required by the automotive sector. HyBoost thus provides a very practical demonstration of what can be achieved today in terms of CO2 reduction using a conventional powertrain architecture and available efficiency improving technologies.

The HyBoost concept is based on a 2009 Ford Focus in which a 2.0L naturally aspirated four-cylinder gasoline engine has been replaced with a 1.0L three-cylinder EcoBoost engine. In implementing this 50% downsizing by swept volume, the research team delivered zero degradation in driveability, performance or acceleration.

This is achieved through the use of a combination of technologies including a belt starter-generator to provide regenerative braking and stop/start, exhaust energy recapture through electric turbo-compounding, advanced, cost-effective lead-acid batteries and super-capacitors to provide energy storage, and electric supercharging to provide improved transient response and avoid the pitfalls of turbo-lag that otherwise place a practical limit on the potential for downsizing.

The form of ‘intelligent electrification’ powertrain architecture being evaluated in the HyBoost concept aims to break the previous boundaries of gasoline engine downsizing by implementing a practical mix of technologies aimed at recapturing braking energy and re-using this for supercharging at critical points in the operating envelope. Coupled with well-proven micro-hybridization techniques, HyBoost thus offers the prospect of significantly reduced carbon emissions from a gasoline engine powertrain in a more commercially attractive package than full hybridization, while delivering uncompromised or even better performance. We look forward to sharing the results of this very promising research project in the coming months.

— Ricardo chief technology and innovation officer Professor Neville Jackson



I've been intrigued by the idea of using undersized ICE engines with just enough supercapacitor for regenerative braking and 0-60 boost, stop/start, and little else. It seems like the lowest cost addition to increase powertrain efficiency. I wonder what the described system does to the cost of a Ford Focus?

That doesn't seem like what this is, though. This sounds like it uses braking energy to power an electric supercharger. It avoids turbo lag, by scavenging and storing braking energy instead of exhaust energy. Meh. Dunno if that impresses me as much.


This is some of many ways to raise the ICE vehicle efficiency instead of making them bigger and bigger year after year. One can wonder why the 20+ major vehicle manufacturers did not incorporate those relatively easy technologies one or two decades ago. CAFE was not severe enough?


The once 'big three' have to be be beat over the head with regulations, bankrupted, or threatened by a viable alternative before perhaps deploying significant innovation.

20 something mpg was good enough for a hundred years, sort of like the golf ninth hole still plays the same.

We'd still be using land line Morse code if electronics were auto innovative.


This is essentially what I was calling for a while back. Either it was obvious to anyone skilled in the art, or someone was reading me (I vote for "obvious").

Will S

Will be curious to see actual data on mpg, etc.


What are you guys talking about?

1. Obvious? It has been widely known for YEARS that mild hybrids are the most cost effective hybrids, best use of batteries, etc; but apparently lack ego boost.

2. The 200 major vehicle manufacturers are doing exactly what they were created to do – make what people will buy.

Roger Pham

I am having a little hard time imagining a "an extremely cost-effective, ultra-efficient gasoline engine in a C-segment passenger car..." yet having an electric supercharger, a BAS electric motor, and an electric turbo-compounder, and sophisticated power electronics to manage all these electrical! All potentially high-price and complicated items.

Recall from history, the Wright Cyclone R-3350 aircraft radial engine, with an engine-driven supercharger and a Power Recovery Turbo-compounder. This particular set up was notorious for having high failure rates due to overheat melting of the sodium-cooled exhaust valve and piston damage from the "Parts Recovery Turbine" down stream from the exhaust port. Adding the turbo-compounder significantly raises the engine temperatures, for obvious reasons. This potential for overheating, in a 1-liter puny engine with very little thermal mass and blown with a supercharger serving a C-segment passenger car?

By contrast, the 4-cylinder Atkinson-cycle engine runs significantly cooler due to the over-expanded exhaust. The over-expansion of the power stroke raises efficiency as much as the turbo-compounder, without any extra costly, high-maintenance hardware.

For low-cost, full electric hybrid conversion of a 4-speed automatic Ford Focus, try this:
New intake cam shaft to simulate Atkinson cycle. Remove the torque converter and install a 20-30 kW motor in its place.
Replace the existing starter and alternator with a 5-10 kW BAS, and position the wet clutch between the motor and the engine. Remove the spare tire and put in its place some Lithium battery of about ~1kWh capacity. (New cars has tire pressure warning system to allow the owner to re-inflate a nail-puntured tire in time to take to the shop before running completely flat!)
Replace the ECU with a new ECU module designed for the hybrid conversion. This should be an OEM-engineered effort to be done at the dealer only, and not at a mom-and-pop garage!

Voila, a low-cost and highly efficient full electric hybrid without sacrifice in performance nor trunk space, using minimum electrical components and cost. The fuel efficiency will pay for the cost conversion in some odd years. The saving in imported petrol and in CO2 emission will be priceless!


Roger, what you're imagining is a C-class car engine being operated at airliner cruise power and duration. There has also been more than 50 years of improvement in alloys and other technology since then.

A 1-liter engine has more than enough power to push a C-class car at cruise speed, even up reasonable grades. The car only needs a 2 liter engine to meet acceleration demands, and those last relatively briefly. The turbogenerator can operate from impulse energy, harvesting power that would otherwise be dissipated in the muffler (which is still needed even on Atkinson-cycle engines). This is squeezing much of the remaining efficiency improvement out of the 4-stroke engine.

Roger Pham

I dramatized it a bit when mentioned the radial engine with turbo-compounding. Certainly, technology has improved since then. However, micro turbines and centrifugal compressors are not nearly as efficient as piston expander or piston compressor, so I doubt if you can harness more exhaust power from a turbo-compounder than in an Atkinson cycle over expanding piston.

Still, a turbocharged engine always runs hotter, and many kids who own a small supercharged vehicles would often floor it around town and may drive it at 80-90 mph down the highways, and that 1-liter engine may not last long, I'm afraid.


I believe RP is basically correct on the affordability of such a combination - after all they even call it a "demonstrator".
But if you install a 20-30 kW motor in place of the torque converter you should eliminate the starter and generator completely.

And turbochargers have required durable exhaust valves since the 60s.

Buy turbochargers and intercoolers are expensive and complex.
You’ve got your radiator, AC condenser, AT cooler, oil cooler then add an air-to-air intercooler - umm, yes.

Atkinson engines have poor specific hp/lb.

Direct injection seems to be providing a significant step improvement and is synergistic with other MPG technology.

There are no easy answers.

And a "why don't they just do it" shows a deplorable lack of business sense.


Advertising endless 80% empty trucks and SUVs shows a deplorable lack of business sense.


The issue of small engines supplemented by limited energy storage such as supercaps is that you quickly run out of ommp going up an hill... but it works very well in the flatlands.

Its going to be very hard to improve on a plug-in Prius with lithium-ion batteries.

Atkinson engines have poor specific hp/lb.
That's what the Miller cycle is for.
The issue of small engines supplemented by limited energy storage such as supercaps is that you quickly run out of ommp going up an hill.
I've driven a rig loaded to more than 6000 pounds, with the added drag of a trailer, up a long 5% grade at 65 MPH on about 90 horsepower. The continuous demand for a C-class car alone would be maybe half that, and 45 HP/liter is practically loafing.
Its going to be very hard to improve on a plug-in Prius with lithium-ion batteries.
Only if you can get the batteries, and at a reasonable price. I really like plug-ins but I have to admit that we just don't have the capacity in the supply chains to build what it will take.

The new Prius PHEV can and will be improved with lighter materials, less drag, improved batteries, controller, e-motors, ancillaries, lights, ICE genset, tires, on-board electronics, driver's assistance etc.


Engineer-Poet wrote:

I really like plug-ins but I have to admit that we just don't have the capacity in the supply chains to build what it will take.

I like fairy dust and unicorns, too, but that doesn't mean they are anything but pure fantasy.

Until batteries last well over 100k miles, have charge densities greater than or equal to lithium ion AND cost less than $100 per KWH, I doubt they will ever pay for themselves in any drivetrain. The key is the cost per service mile and we know PHEVs just don't cut it. Regular hybrids pay for themselves long before PHEVs.

I suppose that could change if gasoline were 10 dollars or more a gallon. But I think you can make gasoline from plants for less than that even if oil is completely gone.



The oil in your car doesn't last 100,000 miles. The starting battery probably doesn't either. You can replace things regularly as long as they're cheap.

I'm disappointed that the actual performance specs of the Firefly Energy 3D and 3D² technologies were never published. They had the potential to be very cheap.

Gasoline from plants (or anything containing fixed carbon) is possible, but the NPP of planet Earth isn't sufficient to make significant amounts that way.


"Advertising endless 80% empty trucks and SUVs shows a deplorable lack of business sense."

What? They sold many trucks and SUVs, so if the adds increased those sales, even by only a few percent, they showed good business sense.

Buying a truck or SUV, even when gas was cheap may or may not not have shown good business sense, depending on your use for it.

Buying an EV when batteries are expensive and gas is $350/gal likely does not show good business sense, unless you put many more city miles per year on it than average.

But batteries are NOT cheap.


TT...reality is that we (the majority) don't really buy what we need but what we're told to buy? Otherwise, why would anybody drive to work, to school or to the shopping center in a huge 4 x 4, SUV or in a 3+ ton 21-inch wheels pick-up etc? Don't we know better? Have we lost the capability to reason or to think straight? If so, an extended recession may not be that bad or may be part of the cure.

Roger Pham

It was not the drivers who demanded the mfg's to make those monstrous SUV's. It was the other way around, marketing from the automakers.
When I grew up, there was only sedans, station wagons, and pickup trucks, and life went on just fine. The larger station wagons like the Chevy Impala or Caprice, or Ford Crown Victoria can seat 8-9 persons in 3 large benches, and were perfect for large families. Then, Lee Iacocca invented the minivans to speed up demands for new vehicles, and it became a hit, replacing the station wagons. Soon, every soccer moms had got to have a minivan. Then, once the market for minivans was saturated, Detroit decided they must invent new products in order to sell more new vehicles, and through their ingenius marketing, everyone was convinced that they must drive a honking big SUV as a status symbol of machismo. The affluent soccer moms felt subconsciously threatened by these monster tanks, that their minivans can no longer afford enough protection for their precious little kids when broadsided by these monstrosities, so, they, too, must drive a honking big SUV's...and you know the rest of the story.

For HEV's, there were hardly any marketing effort at all! Mfg's just wanted to sell a few to show off their Green Washing...There was no huge profit margin in HEV's as in SUV's. They don't really care if they'll sell any HEV at all, since the profit margin for HEV's were just about the same as for non-HEV. Jusk ask Bob Lutz when he developed the Volt! He surely didn't expect GM to make any dime off of it!

But now, there will soon be released the Prius v having a larger size and 68% larger cargo space yet very competitively-priced, to be followed by the Prius + that can seat 7...Also to be released is a PHEV Prius competitively priced for early adopters...We will see that HEV and PHEV's will snap up market shares like never before.

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