The first was spurred on by a Knowledge Network documentary I watched this evening on Enhanced Geothermal Systems (EGS). This is a process being develop to bring Geothermal potential to regions of the world that do not have easy access to hot rock, water reservoirs, and fracturing of the hot rock to allow harvesting of the steam (currently only accompanying about 10% of the earths surface and may be expandable to 60-80% utilizing EGS). The process involves creating the underground water reservoir in areas that have dry hot rocks and using techniques from the natural gas industry to fracture the rock after creating a 'man made' water reservoir over a hot rock location (rock in close proximity to Magma). The result is the same super-heated steam available in true geothermal regions. The documentary also covers research into new drilling techniques that use flame jet instead of a drill bit to drill through solid granite up to 10X the speed of conventional drilling.
This is a National Geographic production and I was unable to find an official source for the video but did find this YouTube video in English with Portuguese subtitles.
The second potential energy source is new way to create nuclear power. Nuclear power has created a huge divide between those that support it and those that do not. On the one hand it can create almost limitless volumes of energy with relatively low emissions. The catch however is the technology utilized throughout the world is very inefficient (3-5% of the energy is utilized in the fuel rods before they become waste) and this leaves behind spent fuel with a very high radio active content and in huge volumes. The real drawback is that this waste has a half life in the several hundred of thousands of years. The final concern, propelled to the forefront after the devastating Japan earthquake in 2011, is that current technology is very hard to stop once it gets going. The Fukushima nuclear plant will take decades to cool down the cores of the three stricken reactors and decommission the plants (it is taking 3000 people daily to keep the reactors cool, 2 years after the explosions).
But what if another technology existed that would burn the fuel to much higher efficiency, would created a fraction of the waste volume, the waste would have a half life in the hundreds of years instead of hundreds of thousands of years, and the fusion process could be shut down almost instantaneously and without human intervention in case of an emergency? Liquid Fuel Thorium Reactors (LFTR) promise just that. This reprint from the American Scientist is a great introduction to the technology and the missed opportunities that we have had. It also outlines some of the challenges to switching technologies in the future (mostly political).
Some benifits to LFTR:
- liquid fluoride salts are impervious to radiation damage eliminating the shutdowns needed to change out traditional fuel rods every 18 months.
- It is much cheaper to fabricate the fuel
- Because the liquid fuel does not break down due to thermal cycling and radiation, it can stay in service until a much higher percentage of the fuel if burned up
- Fission poisons like Xenon (materials that absorb electrons reducing the output of the fission process) are easy to remove from liquid fuel because the bubble to the surface. Other unwanted materials are easily removed from liquid fuel by fluorination or plating techniques, greatly prolonging the viability and efficiency of the liquid fuel.
- Wastes created byLFTR only need a few hundred years of isolated stroage vrs a few hundred thousand years for sold fuel rods.
- The liquid salt coolant in a Salt Nuke is not under pressure (reduces the cost by not requiring a pressure containment building)
- A Salt Nuke can be designed to auto extinguish during any calamity that causes a power failure. Once a frozen salt plug melts, the core would dump into a sub-critical catch basin.
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