MHD POWER GENERATION

A MHD (magnetohydrodynamic) generator or MHD dynamo transforms thermal energy or kinetic energy into electricity directly.

MHD generators operate at high temperatures with no moving parts. MHD was developed as the exhaust output of an MHD generator is a very hot flame. This is able to heat boilers in a traditional steam power plant.

High temperature MHD was invented as a 'topping cycle'. This adds to the efficiency of normal electric power generation. This is more so when burning coal and natural gas as they are hotter.

There are two types of MHD generator - fluid MHD and mechanical MHD. Fluid MHD uses the motion of plasma or fluid to generate the current that becomes the electrical powrer. Mechanical MHD uses mechanical devices to make the electricity.

The special usefulness of MHD is that it allows an old single cycle fossil fuel power plant to be upgraded to a higher efficiency. This with carbon capture and sequestration can make even old style power plants useful in the futre low carbon economy.

Natural MHD dynamos include the global MHD dynamo. This reacts with with the solar wind (charged particles) and creates the Aurora Borealis.