Hi, I've been watching them as well.
They don't say much about how their technology is supposed to work. From what they do say, they are contravening Maxwell's equations (see wiki
here, or hyperphysics
here).
A basic electric generator can convert mechanical kinetic energy into electric energy, basically by driving a conductive loop through a magnetic field. The energy source for this is whatever drives the generator, such as a diesel turbine motor. Total power consumed in burning fuel = power losses (making heat through friction, etc), + useable power output.
Steorn claim to be able to switch sections of the magnetic field in and out, in such a way as to generate more power output, than the power input. This contravenes Maxwell's equations, as energy is involved in creating and collapsing the field.
If one were able to switch the field in and out, without consumption of power, then the claim would probably hold. However, this doesn't appear to be possible, as one of the basic principles of physics is that there is a continuity of energy and matter, so the energy can't just come from nothing.
Steorn claim to have achieved 400% efficiency in some tests.
Steorn are currently involved in a validation process, which has a report due this month (I think). The validation personnel is supposed to have included a number of physicists. Might be fun to read, but I'm not expecting too much. The company is very thin on disclosing real information.
Hope that helps.
Oli
