Energy Invention: Keeping an Open Mind

August 3, 2008 – Vol.13 No.20

ENERGY INVENTION: KEEPING AN OPEN MIND.

Solar, wind, ocean, geothermal energy: All good stuff, but it’s likely that there are still more clean energy possibilities out there yet to be discovered and even further from being commercialized. We have to keep an open mind on those possibilities, not close it up. The human race is not done inventing quite yet.

New ideas continue to flow in. Here are a few examples:

--- While solar photovoltaics continue to evolve into better products so does concentrated solar power (CSP). The latest innovation may come from the most experienced builder in microturbines, Capstone Turbine Corporation and HelioFocus, an Israeli CSP developer. HelioFocus has placed and order with Capstone for the development and modification of Capstone Turbine’s 65-kilowatt C65 MicroTurbine (R) to operate on solar energy.

The HelioFocus Solar Concentrator technology focuses enough solar energy to provide an equivalent amount of combustion heat as a gaseous or liquid fuel to drive the microturbine. This fuel-free renewable solution should offer higher solar conversion efficiencies over traditional solar photovoltaic systems. In addition, the increased power density of this system is expected to reduce the amount of required real estate for siting these systems compared with photovoltaics.

(There’s no reason to think that combining concentrated solar thermal energy with a proven technology, Capstone’s turbine, won’t work as stated by the company.)

Under the initial phase of development, Capstone will make modifications to the existing microturbine to operate on superheated air and integrate the microturbine with the HelioFocus solar concentrator system

--- Despite its problems (principally waste storage) nuclear energy does serve us well. Nuclear power is greenhouse gas-free, and is reasonably priced, though not as cheap as coal.

Hyperion Power Generation thinks a new solution to nuclear power is to build small nuclear powerplants – really small, about the size of a hot tub – and bury them underground for power in remote locations. The Hyperion Power Module (HPM), which was conceived at the Los Alamos National Laboratory and licensed to New Mexico-based Hyperion, would be powerful enough to energize a good-sized community. Each module would be under 24/7 armed guard for security, and when the uranium fuel is spent the module would be dug up, sent back to the company for its fuel to be recycled.

Each unit would generate 70 megawatts of thermal (heat) energy, or 27 megawatts of electricity via steam turbine providing enough energy for 20,000 average American-style homes. Cost would be $20 - 30 million each.

For now, it’s hard to imagine any community allowing a nuke under its streets. Nuclear power doesn’t come under the loose definition of green energy either. But the current perceptions of nuclear may change if fossil energy costs continue to rise. The company is planning market introduction in 2013.

--- Then there are ideas that are just that, for now, but could become energy solutions in the future.

Philip Hardcastle, a geophysicist and electrical engineer from Australia has one. He thinks a prototype Rotating Thermionic Generator (RTG) should be built using government funds with the resulting technology freely dispersed for the good of the world.

Thermionics is a branch of electronics that deals with the emission of electrons from matter under the influence of heat. More simply, it’s the science focused around electricity that is generated when metals are heated.

Common theory in thermionics says that two metals must be used, one very hot, one cold for electric current to flow. Hardcastle offers a different twist to the science, however. He thinks that high temperature heat and a temperature differential aren’t needed to induce electrons to depart from a metal surface to make a flow of current. With his hypothesis electrons will fling off a disk spinning in a vacuum. In this concept centrifugal force causes electrons from the outer rim of a metal doughnut-shaped spinning disk to be flung off, then be sucked back into the hollow center core. Once back in the disk the electrons move back through it to replace those spun off.

One of the more useful properties of metals is the loose atomic bonding of electrons. If they can be flung off easily by centrifugal force with less energy than needed to supply that force, then he’s on to something. Hardcastle says they can a Rotating Thermionic Generator would make more useful energy than it would take to run it, but it is not a perpetual motion machine. Key to the operation of the RTG is a continuing flow of low level heat; ambient room temperature heat would be enough. Ambient energy is free, of course; we get it from the Sun all day long.

Hardcastle says the electricity produced by the spinning disk wouldn’t be enough to use directly but would be used to make electricity by energizing the magnets of a generator.

Some inventions will be proven viable and be developed, eventually into products. (Of the above three the CSP-microturbine appears to have the best near term, possibilities.) Some inventions will fall by the wayside, sometimes even make a comeback. It’s the open mind though, that’s what keeps inventions coming.

Links:

Thermionic Revolution
http://www.thermionicrevolution.com

Hyperion Power Generation
http://www.hyperionpowergeneration.com

Capstone
http://www.microturbine.com