$45B annual windfall for US consumers with a gasoline-engine overhaul? EPA is getting a patent worth knowing about

June 8, 2017 |

In Washington, the US Patent & Trademark Office has just issued a “notice of allowance” for a patent by the U. S. Environmental Protection Agency for a high efficiency, high compression engine that would reduce the cost per mile for the American driver by 26.2 percent, compared to using straight gasoline and a conventional engine.

That would create a savings of $45.79 billion per year for US drivers compared to using conventional fuels and engines, according to the Digest’s analysis of fuel economy, gas prices and miles driven.

Overall, the savings is 13.5 percent compared to current US spending, because drivers are already reducing their fuel costs by 14.66 percent through the use of 10 percent ethanol blends, which create 2% lowered fuel economy compared to E0 gasoline (“straight gasoline”) but is priced 50 cents per gallon less than E0 fuels, according to the data at E85prices.com.

The EPA researchers at the National Vehicle and Fuel Emissions Laboratory found that “combined with an optimized conventional drivetrain, the efficiency gain…for E30 should yield an estimated 10% to 12% gain in fuel economy, and thus more than compensate for the approximately 8% loss in fuel energy density compared to gasoline.”

The savings data

Here’s the Digest table of gas prices, fuel economy and market sizing.

The engine and technical backstory

It’s been known for more than a decade that vehicles can utilize low-cost port-fuel-injection, spark-ignition technology with neat alcohol fuels (that is, alcohol levels above 85%) to reach peak brake thermal efficiency levels of over 40%, comparable to state-of-the-art diesel engines. Yes, that means getting diesel efficiency, but without diesel. Here’s the data stream on that.

As the researchers noted in their findings:

“Neat alcohol fuels have been shown in numerous works to offer some significant benefits over gasoline. Their high octane number gives the ability to operate at higher compression ratio without preignition; its greater latent heat of vaporization gives a higher charge density; and its higher laminar flame speed allows it to be run with leaner, or more dilute, air/fuel mixtures. In addition, alcohol fuels generally yield lower criteria pollutant emissions than gasoline lower evaporative emissions due to somewhat lower vapor pressures and, when renewable feedstocks are used, lower life-cycle greenhouse gas emissions.”

But there were technical challenges.

The research team stated:

“These design programs had faced a persistent challenge with hydrocarbon emissions during cold starting, as is typically seen with dedicated alcohol fuel engines using a high compression ratio. Such challenges may be mitigated somewhat through secondary air injection or with more volatile fuel additives such as gasoline.”

Just as important to drivers, there were fuel economy challenges. The team said that similar work performed with E85 had yielding up to 20% fuel economy improvement over baseline gasoline engines, but observed that “nearly a 25% increase in fuel economy is needed to operate economically with E85”, and they also noted the limited availability of flex-fuel engines that can run E85 blends, and the supply constraints that applied.

So, the R&D began with a goal of “focusing on alcohol-gasoline blends in the range of 10% to 50% alcohol content, in which startup emissions can be addressed effectively with conventional oxidation catalysts,” and they found that “High efficiency was demonstrated with fuel blends down to 30% alcohol content. Such fuels may present a more economical and efficient means of utilizing alcohol fuels, and provide a path toward their more widespread, long-term use.”

The technical break-through in compression and fuel tolerance

The most important thing you need to know is that, essentially, the researchers modified a 19.5:1 compression diesel engine for spark ignition (diesel engines use compression, rather than spark).

Now, if you ever ran straight gasoline at that compression, using engine designs we know today, you’d do serious damage, because the highly volatile gasoline fuel wouldn’t wait for the spark and would auto-ignite. Essentially you’d have a series of uncontrolled explosions going off in your engine, causing “engine knock” and the potential for catastrophic engine failure.

So, why is high-compression tempting for engine designers? Well, higher compression means more work efficiency — the fuel’s energy is channeled more efficiently into moving the vehicle down the road. That’s why you get the fuel economy with diesel, that’s why it matters. And, that’s where the properties of alcohols really shine.

As the researchers noted:

“With E30, auto-ignition is avoided, despite the high compression ratio, through the use of a dilute combustion mixture with reduced intake oxygen concentration (e.g., using substantial EGR), reduction of the final compression temperature (T.sub.2) of the fuel/air mixture (through cooling of the intake air and latent cooling caused by vaporization of the alcohol fuel, e.g., during the compression stroke), through the use of a compact combustion chamber to reduce the distance of flame travel, and by retarding the spark timing sufficiently to avoid knocking while having sufficient spark authority to maintain efficient combustion phasing.”

That’s getting technical; if you’re still hungry for more hard data and a dive into the weeds, you are definitely a Gear-Head (wear your badge with pride), and you can do your reverse 4½ in pike position into all the technical goo right here and here and here.

Before we complete our exit from Geekworld, here’s the design they’ve disclosed in the patent app.

And here is the data stream on the engine’s efficiency.

The takeaways

For the rest of us, back to Planet Earth, and your takeaways are these:

1. E30 engines allow for higher engine compression without the negative consequences, and you get 26.2% better fuel economy on a cost-per-mile basis.

2. Yep, that takes into account engine efficiency, fuel energy content and price.

3. Nope, you can’t buy a vehicle with that engine design today. The USPTO is just in the process of issuing the patent — we’ll have to see who licenses, and develops an engine.

4. But yep, that $46 billion in annual savings for consumers is not a made-up number, it’s the real outcome of deploying that fuel and that engine across the US gasoline-powered fleet. If diesel-based drivers crossed back over to gasoline-based engines, or electric drivers traded in to get that kind of savings and environmental performance, the savings to the US economy will be higher.

5. It’s all subject to fuel prices, of course, but given that they are at very low price levels right now, the savings would be even higher.

6. What can you do to get these engines into the market? Talk them up, ask about them.

Reaction from stakeholders

The afore-mentioned Urban Air Initiative is leading the cheering section and the pep rally.

David VanderGriend, President of the Urban Air Initiative:

This action supports and validates years of UAI research and data analysis that high octane ethanol blends are superior motor fuels to gasoline, if engines are designed to take advantage of ethanol’s properties. Here we have EPA agreeing that higher ethanol blends can reduce emissions and acknowledging that engines and fuels must be looked at as an integrated system. Adjusting compression to address the slightly lower energy content of ethanol while taking advantage of the octane is something automakers can do. But the inconsistencies with these findings and the actions of the regulators is maddening. The reason we have not seen these engines coming out of the auto industry is the roadblocks EPA has created keeping ethanol out of the market.

The cautionary note

VanderGriend adds:

“In the Tier 3 Rulemaking of 2016 EPA officials declined to provide a pathway for certifying E30 as an approved fuel after asking for comments on doing so. They have declined to lift unnecessary vapor pressure restrictions on higher blends. They have failed to update lifecycle and emission models that validate ethanol’s positive impact on emissions. And they have eliminated GHG and mileage credits for automakers who have clearly stated they would be able to take advantage of these higher ethanol blends if some credits, which are disproportionately applied to electric vehicles, were available to them. Under the current system automakers are essentially mandated to produce electric vehicles despite the higher cost and lack of consumer acceptance.”

The Bottom Line: Watch out for BAUBO

It’s great news, and we wonder, really, how many inventions come along with a real-world $46B benefit to the US economy that you can take to the bank by simply swapping conventional products for the new and improved one.

So, be of good cheer.

But watch this space for the reaction from incumbents. Someone has to make the car, approve the pathway and blend the fuel. Those parties may not feel they are participating in the same economic windfall as consumers, and may gird their loins accordingly. So watch this space for the the BAUBO, the business-as-usual brush-off.

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