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Supercharged Achates 2stroke features two horizontally opposed pistons per cylinder and two crankshafts
<p><strong>Supercharged Achates 2-stroke features two horizontally opposed pistons per cylinder and two crankshafts.</strong></p>

Achates Finding Traction With Opposed-Piston Engine

&ldquo;Our biggest challenge is responding to all the demands we&rsquo;re getting from the marketplace today,&rdquo; CEO David M. Johnson says.

It’s been a torrid 18 months for Achates Power, the upstart engine developer’s top executive says.

Although the company has been around since 2004 trying to perfect its modern opposed-piston 2-stroke engine and drum up interest from potential partners around the world, it still can’t point to a production version of the concept.

But it’s getting close, CEO David M. Johnson promises.

“It’s almost startling how much progress we’ve made over the last three years,” Johnson tells WardsAuto by phone, adding company activity has been building to a fever pitch since mid-2012.

That includes a licensing deal signed in October with Beloit, WI-based Fairbanks Morse, which will piggyback on Achates technology to modernize its long-held lineup of opposed-piston engines that are used in power generation, marine/military and other applications.

The Achates technology is expected to improve efficiency and lower emissions in the next-generation lineup of Fairbanks Morse powerplants, which currently includes 3-, 6-, 9- and 12-cyl. engines producing 1-5 megawatts of power, Johnson says.

“We’re doing a lot of work with them now to apply our technology to their engine and bring it to the next level of development,” Johnson says of the collaboration with Fairbanks Morse. “That really will make it a market leader.”

Last December, Achates landed a contract with the U.S. Army Tank Automotive Research, Development and Engineering Center (TARDEC) and AVL Powertrain Engineering to design and build its Next-Generation Combat Engine.

The project, due to be completed over 27 months, is aimed at developing a 70-hp/L, highly efficient engine that can run on a variety of diesel fuels.

The developer says it now is working with numerous clients on additional Achates-engine applications.

“We’re seeing broad-based interest across various segments of the industry and regions of the world,” Johnson says, “from power generation, like Fairbanks Morse engines, to light-duty and heavy-duty vehicles, to aviation.

“We have contracts and work going on in every market, Asia, Europe, U.S.”

Johnson won’t put a time frame on application in a light vehicle, but he is convinced the company’s biggest impediments to production now are time and resources, not lack of interest.

“Our biggest challenge is responding to all the demands we’re getting from the marketplace today,” Johnson says. “There was a point in time when we weren’t getting that demand; we were excited but it was a challenge to get others excited.

“Now with the (test) data sets that we’ve had and the scrutiny that we’ve had from our customers, there’s a wave of interest and confidence in what we’re doing that is very exciting for us, but a challenge to manage all that interest simultaneously.”

In 2010, Johnson told WardsAuto Achates was targeting a 10% fuel-efficiency advantage over a comparable diesel, while meeting the world’s toughest emissions standards. But that outlook only has improved over time.

“Three years ago, we had the first breakthroughs that demonstrated we could meet emissions standards and be more efficient than conventional (4-stroke diesel) engines,” the CEO says. “But we’ve essentially tripled our benefit.

“Now we’re achieving results that demonstrate a 30% advantage. It’s really quite significant.”

The supercharged Achates 2-stroke features two horizontally opposed pistons per cylinder and two crankshafts.

The block can be made of cast iron or aluminum, depending on application, and the engine can run on a variety of fuels. It employs a high-pressure fuel pump and common-rail and solenoid-based diesel injectors rated at 32,000 psi (2,200 bar) and capable of five injections per cycle.

It would use a urea-based selective catalytic reduction system in most on-road applications, but that likely would not be needed for stationary or off-road use.

There is no cylinder head or valvetrain, and overall there are about 40% fewer parts in an Achates 3-cyl. than a conventional V-6 diesel, the company says.

“We typically have a weight and size benefit (vs. comparable diesel engines), and we see that playing out pretty consistently across the various applications,” Johnson says.

The executive is guarded about the company’s business potential, saying only that he expects to see Achates engines in production within the decade, much sooner than that in the case of the Fairbanks Morris powerplants that will incorporate his company’s 2-stroke technology.

He declines to reveal how many Achates prototype engines have been built for testing or how many test hours they’ve compiled. The company’s website says the engine has run for more than 4,000 hours on dynamometers.

Johnson says the powerplant will meet Euro 6 emissions regulations and that Achates plans to deliver a paper at the 2014 SAE World Congress in Detroit showing it also can achieve even tougher U.S. Tier 2/Bin 2 standards.

“(That’s) the lowest stated (regulation) in the world today that I’m aware of and is the foundation of Tier 3 emissions legislation to come,” he says.

The secret, Johnson says, is the relatively flat nature of the engine’s fuel map.

“Instead of having a single operating point that demonstrates good efficiency, we’re able to demonstrate good efficiency at various operating points across the engine map: low speeds/low loads, mid speeds/high loads,” he says. “And that has a very big cycle-average benefit.

“So where does it come from? It’s combustion, friction, pumping; it’s all the elements coming together to improve the overall efficiency of the engine.”

Achates does not want to be an engine builder, preferring to license its technology, but Johnson says the company is open to joint ventures and other arrangements with potential partners.

Getting the auto industry to bite on a new concept for light vehicles – or even on-road commercial vehicles – remains difficult, because automakers already have huge investments in plants and tooling to manufacture conventional engines. And while it’s difficult to judge whether Achates’ feverish development work will pan out, it appears the company has gained some traction.

Johnson says forthcoming emissions and fuel-economy laws will continue to turn automakers toward Achates, because the 2-stroke engine can hit those targets without all the expensive add-on technology that will be required by more conventional engines.

Investors and experienced industry veterans seem to agree Achates has potential. In October, the company was able to line up $35.2 million in new financing, and it created an industry advisory board that includes Daniel Hancock, former General Motors global powertrain engineering chief; Bruno Linsolas, former purchasing chief at Volvo Powertrain; and Karl Viktor Schaller, a one-time high-ranking executive at German truck maker MAN, among others.

“We’ve really lined up a tremendous amount of support,” Johnson notes. “As we look at future emissions standards and CAFE standards, we think this technology is the exact technology necessary to meet those.”

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