Opposed-piston engine work is ‘no joke’ – Achates

Under perceptive questioning by a WardsAuto reporter, Achates President and chief executive officer David Johnson claims interest from vehicle builders is serious and will lead to production.

“Some engine manufacturers are retooling plants in certain parts of the world to produce Achates’ opposed-piston engines or are investing in this conversion,” he told WardsAuto. “Existing engine factories need only modest retooling.”

Executives at Achates are convinced their engines, which require two crankshafts and position two pistons in opposition in each cylinder, are up to 50 per cent more efficient than current downsized turbocharged gasoline engines and 30bper cent more efficient than next-generation light-duty diesels.
These percentages seem high, which only raises the question: Why has it not been done before when the opposed-piston two-stroke engine with its scavenging problems has been known about since before te Second World War? With phasing and to make sure the cylinder is well filled, there has to be 'lost' incoming air, surely? Johnson, as ever is unphased.

“We are in a deep phase of commercialization of our technology and have demonstrated on our dynamometers in San Diego that our engines are the cleanest and most efficient engines in the world and therefore are highly relevant,” WardsAuto claims Johnson told journalists recently.

“It’s the technology that has driven customers to our doors,” he said, noting that each automaker is in the process of eliminating its dirtiest engine. “They replace it with their best confidentiality agreements.

Three major automakers, in response to questions from WardsAuto, say they are intrigued by the Achates technology but not working on opposed-piston engines or with the company.

Johnson cannot – and does not – identify the nine customers as he is tied by confidentiality agreements.

                        Achieving next-level emissions reduction

But as autoindustrynewsletter.blogspot.co.uk has reported, there are three additional contracts for military programmes, including a $14 million deal with Cummins Inc. to develop engines for advanced combat vehicles. The US Army has been a customer for five years and revenues from military programs have reached $25 million.

Engine producer Fairbanks Morse of Beloit, Wisconsin, is using Achates technology to update its opposed-piston engines used in power generation, marine, military and other applications.

“We’ve helped them achieve the next level of emissions (reduction),” claimed ex-Ford man Johnson. “They are taking our technology into production now.”

The US Dept. of Energy’s (DofE) ARPA-E research arm has awarded a $9 million grant to Achates, Delphi and Argonne National Laboratory to develop an opposed-piston gasoline compression-ignition engine suitable for high-volume production and to be used in full-size trucks and SUVs popular in the US.

That research programme has yielded a two-stroke three-cylinder (six-piston) engine that Achates will install in two demonstration vehicles later this year. Images of the two test vehicles on a Powerpoint presentation suggest one vehicle is a Ford F-150 and the other a Chevrolet Suburban, according to WardsAuto.

“The reason we went after those vehicles and targeted this product is they have the greatest need for fuel efficiency improvement, and they sell in tremendous volumes in this country,” Johnson said.

Early next year, customers will be able to drive the two demo vehicles, which will meet CAFE 2025, Tier 3, LEV III and Euro 6 emissions requirements, according to Johnson. One will be diesel and the other gasoline compression-ignition.

According to WardsAuto, Achates Power of San Diego, California promises combined city/highway CAFE of 37 mile/gal (6.4 litres/100 km) and EPA fuel-economy ratings of 25/32 mile/gal (9.4-7.3 litres/100 km).

With either fuel, output for this 2.7-litre three-cylinder engine is rated at 270 bhp and 479 lbft (650 Nm) torque. The prototype engine intentionally matches the size of the smallest engine (the 2.7-litre EcoBoost V-6) currently available in the F-150.

“Lop off one cylinder and a smaller, two-cylinder four-piston variant would be lovely for passenger cars,” claimed Johnson. “We have studies going on along those lines now.”

He told WardsAuto that bore sizes can be as small as 70 mm, resulting in displacements as small as 0.6 litres/cylinder.

                    Tremendous amount of spending going on

Having worked previously for Navistar International Corporation, General Motors and Ford Motor Company, Johnson joined the privately-held Achates Power in 2008.

And, as a true ex-Ford man, Johnson can hardly contain his excitement that the “revolutionary” technology he has been promoting for years is now so close to production.

“There’s a tremendous amount of spending going on in our industry globally for engine development. Some of those dollars are flowing to Achates Power, and I can guarantee you those numbers will keep growing because of what we offer,” boasted Johnson.

Johnson continued in simiiar vein: “Basically, OEMs that make engines today will make these engines in the future. I know that because of the work we’re doing with them today. Engines we are working on today go from 50 bhp to 5,000 bhp, for everything from weed-wackers to battleships.”

Some OEMs with whom Johnson is working must be wondering what the man will say next.

In Johnson’s nine years at the company, Achates Power Inc. has grown from 30 employees to nearly 100 and from one building to four, including a facility in the mid-west in Farmington Hills, Michigan to tap into local automotive talent. Achates was founded in 2004. Revenues have more than doubled from 2015 to 2016, it is claimed.

Johnson’s enthusiasm cannot be diluted. “Achates’ OP engine can be tuned to run on any existing fuel,” he claims.

Johnson adds that "zero customers" are asking for an engine that runs on hydrogen. The radiator can be smaller because the engine rejects less heat to the coolant.

As the opposed-piston engine has no cylinder head or valve train and uses components already produced, such as pistons, connecting rods and crankshafts, it should be cheaper. The two crankshafts are geared together.

Fuel is sprayed perpendicular to the cylinder, between the two moving pistons and Achates claims that “because the fuel doesn’t impinge on the combustion-chamber wall, the engine produces very little soot compared with four-stroke engines.”

However, the engine needs both turbocharger and supercharger for adequate breathing. Even so, Johnson, ebullient and as optimistic as ever clams Johnson overall cost savings can be held at $1,500 or more – about 20 per cent less expensive than manufacturing a comparable four-stroke engine.

He further claims that the cost of after-treatment can be reduced 30 per cent because fewer precious metals are necessary and catalytic converters can be smaller.

Johnson reckons a diesel Achates engine also would need SCR (selective catalytic reduction) to scrub oxides of nitrogen emissions, but the SCR tank can be smaller.

Johnson holds back as to whether SCR would be needed for a gasoline version.

“There’s work being done now at Argonne on that subject,” he claims.

                                  NVH? – Not a problem here

As if no problems are in sight for the opposed-piston engine, Johnson continues to enthuse: “Noise and vibration characteristics are not a problem because the opposed-piston engine is fully balanced with one, two or three cylinders, as opposed to the “paint shaker” sensation Johnson attaches to four-stroke engines with the same number of cylinders.

Achates Power claims it has 135 patents (and 178 pending) for the engine, and many are associated with the integration of existing technologies such as common-rail fuel injection, forced induction, charge-air cooling, exhaust-gas recirculation cooling and closed-loop combustion feedback.

According to WardsAuto, despite breathless enthusiasm internally, at least one major automaker, Hyundai, says it is not working with Achates, although they met three years ago.

“Their concept is interesting,” John Juriga, Hyundai’s North American powertrain director told WardsAuto. “However, with a two-stroke engine design, we still have concerns with emissions capability and durability. This technology could be very beneficial in several applications, so it is worth watching.”

Another automaker told WardsAuto that it is concerned about weight and emissions associated with the Achates concept.

Battery-electric vehicles would appear to pose a threat to Achates, but Johnson is convinced Americans will continue to want internal-combustion engines for long-distance driving and that hybrids will continue carrying a cost premium.

“Toyota has been successful with the hybrid Prius. But we say, if you want to make a better Prius, you’d better give it a better engine. That’s what we can do to help Prius,” Johnson said.

With electrified vehicles a financial drain on automakers, Johnson sees this as a problem.

“If the Prius was the solution, then everything would already be hybridized. Toyota has been the leader in that for years, and they still basically have one plant making Prius because they can’t make money on it. We think this changes things quite dramatically,” he told WardsAuto.

Johnson claims the key remaining question is: Which customer will be first to market with an Achates opposed-piston engine in a light-duty vehicle?

“There was a day when I used to come to work and say, ‘I wonder if anybody will ever do this?’” he says. “That day is long since past.”

COMMENT. Well, there was a day, in September 1965, when journalists at the IAA in Frankfurt were introduced to the NSU Wankel engine installed in the futuristic Ro80 might have asked the same question. Or when journalists in June 1992 were introduced and drove down the leafy lanes of Essex, UK, Ford Motor Company’s version of the Orbital Engine Corporation two-stroke engine (remember the Ralph Sarich engine of 1972 – a kind of down-under variation of the Wankel engine also created by the Orbital Engine Corporation) and revealed at the Dunton Research & Engineering Centre? Ford built 60 prototypes for evaluation. The claimed benefits: fewer parts, lower cost, lighter weight. And the Stirling engine? And the automotive gas turbine? Ford had a go at that too under the command of Ivan Swatman, Ford's gas turbine man from Watford, England, who came to demonstrate the truck in the UK. Swatman's sidekick, Art McLean could be equally ebulient about automotive gas turbines. Ford wasted millions of dollars on that programme. And, while we are about it, the hydrogen fuel cell - you can forget that! Oh, and don't forget the Torotrak/Perbury IVT - Ford has had a go with that as well - and General Motors. And look where that has gotten  us. Well, in the circumstances, journalists can be forgiven for saying: “We’ve seen it all before; and we’ll see it all again.” Journalists too have also met many times men of the likes of Johnson. Such men have an enthusiasm which brims over. That is never in short supply. What emerges with more difficulty is the finished result that the auto industry commits to, makes in great numbers and delivers the ever-elusive royalties. The auto industry is surely the toughest and most cruel taskmaster of all.