Jonas writes:

>Biogas to ethanol would then allow you to transport
>fuel without needing natural gas pipelines

You have written one of the most intelligent reasons to develop synthesis gas-to-liquids technology.

Syntroleum, Incorporated has for years been promoting the idea of CO+H2 to synthetic Diesel/jet fuels as a way to monetarize remote natural gas resources. Granted, natural gas is a fossil fuel and therefore not carbon-neutral, but it is better in that respect than coal.

The high seas of the world are seeing more and more ships designed to transport liquefied natural gas, but there are problems with that technology. One problem is that such ships are going to be targeted by terrorists because of the explosive nature of LNG when it gets loose.

I am delighted to hear about the development of syngas to alcohols for another reason: butanol (If anybody is interested, see www.butanol.com) is a good fuel for spark-ignited engines. Being an alcohol, its oxygen content reduces carbon monoxide. Mixtures of alcohols, i.e. methanol-ethanol-propanol-butanol, can be pumped into a car's fuel tank just like gasoline. The owner-operator doesn't have to learn a new procedure, as is the case with hydrogen.

Having had an intellectual romance for years with the idea of methanol as an alternative automotive fuel, I am well aware that CH3OH has roughly half the energy content, gravimetric or volumetric, of gasoline. This would increase the expenditure of energy involved in transportation of fuel, since you would need for tanker trucks to make twice as many trips to keep your friendly local service station in business.

Ethanol is a little better in this respect, as its energy content is ~60% of that of gasoline. But if we throw in higher alcohols, the energy content will be closer yet to that of gasoline. Hopefully too, alcohol mixtures will have good antiknock ("octane") ratings, will be clean burning, and accidental spills will be readily biodegradable.

In the November 2006 edition of Automotive Engineering magazine, they publish a letter I had written in which I advocate alcohol mixtures as a possible alternative fuel for spark-ignited engines.

I am not enthusiastic about alcohol-water mixtures. The energy content of ethanol is low enough (compared to gasoline) as it is. To literally water it down still further doesn't make sense. Furthermore, water isn't free. Look at the rules we have limiting toilets to only a gallon or so per flush, or upcoming rules on how much water a washing machine can use to do a load of laundry.

The objective of switching to non-petroleum alternative fuels from biomass is to reduce carbon loading to the atmosphere from the use or combustion of those chemical fuels. Using renewable energy to add more carbon atoms to any refined fuel molecule, especially relatively pure bio-methane and carbon dioxide, is a huge step in the wrong direction.

Some people, mostly chemical engineers or chemists, argue that low carbon content renewable fuels, i.e. ethanol, methane and hydrogen, have performance and cost issues. These issues are grossly overstated and easily solved with minor adjustments to engines and fuel systems. Efforts to convert biofuels to mimic gasoline molecules simply because they are liquids that may be easier to handle than ethanol or a gaseous fuel are irrelevant to solving the very problems that must be solved to reduce carbon loading.

I question the wisdom of running biogas through a partial oxidation system to make synthesis gas that is then reacted into ethanol. This is a fundamentally inefficient approach and again is a step in the wrong direction. Capture and use the methane and carbon dioxide without consuming the methane to drive the reactions.

We need research to find more efficient and cheaper ways to process wet biomethane at ambient temperatures. We need better ways to separate the methane from the carbon dioxide at low temperatures and pressures so that both chemicals can be put to the most efficient and productive uses possible at the source; anaerobic digesters can be designed into integrated facilities that can processes waste into value-added methane and carbon dioxide that is used on site. Developing integrated facilities that process wastes and create value-added byproducts at the source before their byproduct carbon compounds are released to the atmosphere is the BEST solution.

Given the evidence that climate change is being accelerated by positive feedback loops, we must start thinking outside the box to eliminate carbon from all fuels.

We need more academic research and development to find news ways to REDUCE carbon emissions to the atmosphere.

Arnold:

Search: Hydrous Ethanol China. DongFeng Motors isn’t giving any specific information about what method they’re using to get hydrogen combustion out of hydrous ethanol. They could also be stripping hydrogen onboard, from the ethanol, like Power + Energy does. They have an extraction process that strips hydrogen out of different vaporized fuels, including ethanol. “The fuel is mixed with steam, vaporized, superheated and reformed into H2 etc…” But for producing hydrogen onboard a moving vehicle, it is much cheaper simply to break or disrupt the water matrix with current from the alternator. And that’s being done by various researchers in numerous different ways, such as a brown’s gas device, or ultrasound, or a water fuel cell, which uses finely tuned frequencies of low voltage and low watt electrical pulses. Again we don’t know just yet how DongFeng is getting hydrogen out of hydrous ethanol. But we’ll know soon enough, when they release their first wave of vehicles powered by the new hydrous ethanol engines. Brown’s gas is just one of several different ways they might be doing it. Still a different way would be to let the internal combustion engine vaporize the water in the hydrous ethanol into superheated steam inside the cylinder. Then zap the vaporous exhaust with current or ultrasound. Then recycle it back through the combustion process as a hydrogen-rich vapor. All kinds of possibilities.