02 August 2008

Better Fuel Cells

Electricity stored in batteries and fuel cells emit virtually no pollution when used. Electric motors are efficient and can be just as powerful as internal combustion driven motors. And, electricity is a less expensive fuel per mile it can move a vehicle than gasoline or diesel or ethanol.

Also, converting electricity production to less environmentally harmful processes (e.g. making more power in the grid from wind instead of coal) can be accomplished in a way invisible to everyone but the power plant operators. Even many electrical utility companies are mere brokers who buy electricity wholesale to power their grids, rather producing it themselves. From an infrastructure perspective, a conversion to a plug in vehicle economy would mostly require some improved plugs in garages and parking spaces across the nation, a fairly minor expense.

Getting reliable electrical supplies off the grid is another matter. Current batteries and fuel cells are inferior to fossil fuels at storing energy. With a better battery of fuel cell, plug in vehicles could be more viable.

All this is the preface to a major advances in fuel cell technology.

First, it turns out that replacing a platinum catalyst in a fuel cell with a cobalt one makes the device much more efficient. In other words, more of the energy put into the fuel cell can be retrieved. A traditional platinum catalyst fuel cell loses a great deal of energy put into the cell as heat. Also, cobalt is cheaper than platinum, so a cobalt fuel cell should be cheaper to build once it is in mass production.

Another advance uses Gore-Tex polymer in place of platinum to increase efficiency, reduce corrosion, and reduce material costs.

A third advance combines the materials in an existing superefficient type of fuel cell known as a solid oxide cell in a new way. This allows it to work at 84 degrees Celsius (183 degrees Farenheit), rather than the status quo 700 degrees Celsius. While this kind of fuel cell is still probably problematic to use in a vehicle, in a residential or commercial building, a solid oxide fuel cell could be kept at the necessary temperature simply by putting fuel cell inside the building's water heater.

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