Methane

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Just in case we didn’t get the message the first time, another oil rig has exploded in the Gulf of Mexico. It was evacuated safely and there appears to be no leak. But given that it was another BP rig, the nooze and politicos are eager to point fingers at the oil company. They shouldn’t. Anyone who does not think that industrial accidents are always going to be a part of a dangerous industry is delusional. The blame for all of these disasters rest with a nation that has an insatiable thirst for oil.

Fortunately, there are many things that can be done. One that I favor involves a step-by-step process by which we move to a methane-based fuel system. Let me explain as briefly as I can.

Methane-producing bacteria which consume organic waste are one of the first forms of life on this planet. Their use on an industrial scale goes back quite far, and includes a fair amount of my own family history. My Grandfather had the Delaware County, PA, sewage treatment facility running energy independently (to reduce cost) in the 1950s. In high school I worked on a project that sought to understand the best conditions for small-scale operations converting garbage to methane in clay pots for Haiti. This is very well known stuff.

There are many problems with producing methane on this kind of scale, however. The gas that bubbles off contains a lot of carbon dioxide and a little bit of hydrogen sulfide. It’s also at very low pressure and not suited for huge industrial scale. How we use methane, a k a “natural gas,” now shows us how to get around these problems, however.

Methane currently is burned for heat (about 60 percent) and electric generation (24 percent). Heating, as we know it, is generally done on-site with a furnace in every building.  Given the way that methane production from garbage works best on a small scale, the idea of a methane digester as part of the power plant of every house – or at least large building – could make a lot of sense.

Electric generation
may seem a bit more difficult in a distributed network, but it also has its own advantages. Electricity is never generated at greater than 40% efficiency because of important thermal limitations – it’s just not possible without a completely different technology than burning. That  60 percent which is wasted goes off as heat, which can be used to heat water and living space.

The vision, therefore, is a system in as many homes as is economical in which the garbage all goes through a big grinder, is mixed with the sewage, and then passes to the methane digestion system operating at very low pressure. From there, it goes to a burner and a small electric turbine.  Such a system would likely cost tens of thousands of dollars, but would replace all boilers in a house – and is still cheap compared to both the building and the energy that does not have to be purchased from the outside.

How much energy can be made by such a system? It’s unclear exactly, but my own back-of-the envelope calculation suggests it is between half and all of our non-industrial heating and electricity. That’s about half of the energy this nation consumes. Such a system would free up whatever “natural gas” that we get form the ground to be used for synthesizing fuels or other industrial uses where clean high pressure sources are needed.

If you buy this vision so far, let me take this to the next level. In order to move this direction we can start replacing nearly all other fuels with natural gas, something that has recently been shown to be plentiful. Biogas (what the product of methane digesters is commonly called) and natural gas are both methane, so the transition can be made much easier.

With this vision we are, for the time being, still drilling in the gas fields of the Gulf of Mexico. But we would be doing it as part of a strategy to transition away from oil and eventually away from non-renewable resources. It would also dramatically help our balance of trade, a major source of economic problems, as we could gradually reduce the oil we have to import (and which often comes from nations that clearly do not share our values).

Moving towards a renewable methane economy will take some coordinated research and planning. It’s something that our government can do for us which does not cost a lot. It may not satisfy all of our energy needs, but it can likely satisfy a lot of them. All it takes is a commitment to intelligent use of resources, something which is the first thing to go when talking heads become shouting heads.