14 Feb 2009

The Future of Energy Transmission

Using Methane to transmit energy

I doubt that we will, in the long term, transmit electricity from wind turbines. It makes far more sense to use the electricity onsite to generate methane (or methanol for remote areas that need a tanker collection) and plug it in to the existing gas network. The technology for this is not yet cheaply available, but people are working on it.

    Methane generation blows all the objections of the doubters out of the water:
  • It can be stored easily, so you never need to leave a turbine idle when it's not needed.
  • It can be shipped to every home and business in the UK with ease, and exported to generate revenue.
  • It can be used as a feedstock for heavier liquid fuels and plastics, eliminating the need for fossil fuels completely.
  • It can be burned, if necessary, in gas-fired power stations for baseload and high-demand electricity use.
  • Since it is made, in this instance, from water and CO2, there is no net cost to the environment*.
  • You can use all types of renewable energy, including microgeneration, to power the same distribution network with zero load balancing issues.
  • You can provide every home and business with its own methane-powered generator, making electricity transmission a thing of the past.

*beyond the hardware and inevitable but hopefully minimised leaks

Imagine replacing every eyesore pylon with a turbine?


Methods of Generating Methane or Methanol

Bearing in mind that free methane is an extremely bad idea I thought I would raise a few ideas about how to go about generating methane on demand using just (sea) water, air and ambient energy (which may or may not be turned into electricity) such as wind, waves, tides and sunlight.

The first method is an engineered organism, derived from methanogens.

There is a kind of autotrophy which is far less familiar. This kind is labelled chemoautotrophy because it relies on chemical processes rather than light for the energy needed for food production. Instead of dumping oxygen, these organisms dump other metabolic waste products. Methanogens, the ones with which we are most concerned, dump methane. Although numerous organic molecules, including acetate, formate, and methyl alcohol, can be used as the source of carbon, the simplest methanogenesis reaction employs carbon dioxide and hydrogen:

CO¸2+4H¸2ÆCH¸4+2H¸2O
(carbon dioxide)+(hydrogen)(yields)(methane)+(water)

Source

So, generate a hydrogen-rich atmosphere in a reaction chamber filled with these organisms using hydrolosis, syphon off the methane waste product, recycle the water into the hydrolysis section, and you have a methane-generator that also oxygenates the surrounding seawater. As they grow, they will need a nutrient stream, but if they are able to feed off their own dead, that could be self-contained. Otherwise, they may need an effluent stream, such as sewage, to live off, the remnants of which might prove effective fertiliser for the oxygen-rich waters.

Alternatively, the technologies developed for coal gasification may offer a more mechanical way to achieve the goal, given a way to concentrate the CO2 and reduce it to CO (perhaps using focused beam solar)

Source

The most active organisation in this area is, however, Nasa who are looking at ways to generate methanol from CO2 in the Martian atmosphere. They do say in the linked article, talking about potential commercial applications:

Current methods of methanol production yield about 27 million metric tons worldwide per year, with the principal feedstocks being natural gas, coal, and wood. All of these have other applications. In contrast, a MMISPP based methanol factory could use renewable energy sources to combine the CO2emissions from existing industrial plants (such as steel mills) with water to produce methanol, thereby supplying the economy with large quantities of storable fuel, while reducing or eliminating steel mill CO2emissions.

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