Achates Power Cites “Huge” Improvement in Diesel Fuel Savings, Emissions
San Diego’s Achates Power, a startup developing a radical new design for a diesel-powered truck engine, is blowing its own air horn today about its progress in demonstrating significant improvements in the efficiency and performance of its engine.
Through a series of tests that began just over a year ago, Achates says its prototype has shown improved fuel efficiency, while also meeting the new EPA10 emission standards for heavy trucks, which seek a seven to 20 percent reduction in greenhouse gas emissions by 2018. Achates says its independently verified tests show a 20-percent reduction in diesel fuel consumption when compared to the Power Stroke diesel engine that Ford introduced in April for its Super Duty truck line. (By coincidence, Xconomy San Francisco editor Wade Roush has a story today about efforts by ATDynamics of South San Francisco to help the trucking industry shave fuel costs by reducing drag.)
Achates has designed its two-stroke, “opposed-piston” internal combustion engine to be smaller, lighter, and more efficient that a conventional heavy-duty diesel engine with separate, in-line cylinders.
“If you’re in the industry, everybody knows that opposed-piston engines have the potential to be more efficient,” says Achates CEO David Johnson. “But the vast majority of engineers say, ‘Yeah, yeah, that’s all true, but you still have to meet these tougher emission standards.’ We did that more than a year ago, in September 2010, and we’ve consistently improved since then.”
Johnson previewed Achates’ engine design in a presentation at UC San Diego last year at the Xconomy Forum on the Rise of Smart Energy. Instead of cylinders that operate independently under a cylinder head, the opposed-piston design puts two pistons inside the same cylinder. Internal combustion occurs in the space between the two pistons as they come together, driving each cylinder outward, in the opposite direction, in what’s known as a two-stroke cycle.
Because Achates’ design has no cylinder head, the engine is lighter. And the dual-piston design means compression ratios are higher, so devices used to measure torque, or power, show the design gets more power for the same amount of fuel.
In a comparison with Ford’s Power Stroke engine, Johnson says its tests show similar emission levels out of the engine and reduced weight, cost, and complexity of the engine itself. Achates says its test also showed less than 0.1percent fuel-specific oil consumption, a measure of fuel efficiency within a crankshaft-design reciprocating engine.
“The most efficient engines on the planet today are four-stroke diesel engines,” Johnson says.
The type of four-stroke engine in an 18-wheel tractor-trailer “Class 8″ truck—the long-haul trucks that move most of the nation’s freight—typically uses about 20,000 gallons of diesel fuel a year, Johnson says. Achates says its 20 percent savings in fuel consumption is the result of ongoing enhancements, hardware upgrades, and more than 2,500 hours of testing at its San Diego facility. In today’s statement from the company, Johnson says, “As commercial and passenger vehicle manufacturers continue to seek improved fuel economy, our data speaks for itself and sets Achates Power apart in the market as a key player in the future of clean, efficient and cost-effective vehicle transportation.”
In a phone interview, Johnson says, “If you think about a 20 percent improvement, you’re saving about 4,000 gallons a year, and at $4 a gallon, that’s about $16,000 in operating cost savings each year. That’s huge. It’s a huge, huge change.”
If all trucks in the United States used Achates’ engine, Johnson adds, the cumulative fuel-cost savings would amount to $24 billion a year.
That’s wistful thinking, of course. Johnson concedes that Achates’ technology remains in early-stage development. The company has made only prototypes so far, and has a long drive to get to even limited-rate production. Still, Johnson says the company’s business plan calls for licensing its technology to industrial partners with the know-how to make heavy-duty diesel engines.
Since the company was founded in 2004, Acates has raised more than $50 million from its venture investors, Johnson says. They include Sequoia Capital Partners, RockPort Capital Partners, Madrone Capital Partners, InterWest Partners, and Triangle Peak Partners.
Founder James Lemke holds 89 U.S. patents and is a member of the National Academy of Engineering. Earlier in his career, Lemke was the research director at Bell and Howell Research and an adjunct professor at the University of California, San Diego. One of Achates’ initial investors was the late John Walton, son of Wal-Mart founder Sam Walton.