Using electricity to shape flames sounds like a weird anime superhero power. But it’s real. A company called ClearSign Combustion has found a way to do it and their innovation would reduce pollution from power plants.
Pollution from power plants is mostly from particulates – that’s what makes smoke black from a coal plant, for instance. The reason is that most flames don’t burn perfectly. There’s always a little fuel left over, which gets shunted out the smokestack.
ClearSign’s technology puts two electrodes in the combustion chamber. The electrodes generate an electric field that alters the path of positively and negatively charged ions in the flames.
The electrodes can control the flame shape, which encourages the fire to burn more of the fuel. In a demonstration video the company showed a flame being reduced to half its size, and since the amount of energy was the same, the flame was effectively twice as intense. The technique can eliminate a big portion of the soot from a typical furnace and it removes a lot of nitrogen-oxide compounds as well.
The system requires high voltages, but small amounts of current. The company says the electric power used is only a small percentage of what’s in the flame itself.
One big effect of this kind of technology is eliminating the need for filters or other pollution control technologies, which are expensive to install, especially on older plants. This could be a very big deal in developing nations, where the expense of fully retrofitting old plants can be prohibitive.
ClearSign’s technology hasn’t been widely commercialized yet, though it signed a development agreement in April with Grandeg, a European company that makes wood-pellet burners. The company says in its quarterly reports that it is in talks with several customers, mostly power and waste disposal companies.