Showing posts with label Fossil Fuels. Show all posts
Showing posts with label Fossil Fuels. Show all posts

Thursday, 27 February 2014

Pacific Northwest National Labratory develops a new Algae fuel ready in about an hour.

Diesel created by algae has been on the radar for a few years now but is still only available in low volume pilot plants and is heavily subsidized.  Once of the largest stumbling blocks has been the energy needed to create the dry algae used by the previous processes.

PNNL has created a process that can work with wet algae (80% water) saving vast amounts of energy and time.  Their new process creates usable crude in as little as one hour.  The process also allows for usable gas to be extracted from the waste water stream increasing the efficiency of the process even further.

This is a large step in the right direction in getting the process closer to the efficiency and scalability needed to compete with the fossil fuel market.

You can read more about this innovative process here.

The process starts with whole green algae slurry with water contents between 80% and 90% (Photo extracted from PNNL)
Under high pressure and temperatures that mimic the conditions found deep in the earths crust, the slime is converted into a light crude that can be refined in a traditional manner into gasoline, diesel and jet fuel. (Photo extracted from PNNL)



Sunday, 15 December 2013

Corn Based Ethanol - Why?

Like the author of an article I just reviewed, I too question the logic of creating 'fuel' from food crops.  Why would we create an industry that takes food out of our mouths while at the same time most likely consumes more energy than it produces.

Alex Wilson of GreenBuildingAdviser.com wrote in his article 'Ethanol Under Fire'

"Depending on whose study you believe, it either takes a little more or a little less energy to produce corn-based ethanol than that end-product contains. That EROI ratio ranges from 0.8:1 to 1.5:1, depending on the study."  "Any time the EROI is less than 1:1, it takes more energy to produce the fuel than the fuel contains. Even giving the ethanol industry the benefit of the doubt by assuming the actual EROI is 1.5:1, that means to produce a gallon of the fuel takes two-thirds of a gallon (equivalent) of fuel — diesel for tractors and combines on the farm, natural gas to produce nitrogen fertilizer, natural gas and electricity at the ethanol plant, and energy to ship that fuel around the country." "By comparison, the ethanol produced from sugar cane in Brazil has an EROI closer to 8:1 — for every gallon (equivalent) invested you get about eight gallons back out.
No matter whose numbers you believe, from an energy standpoint turning corn into ethanol to fuel our cars makes little sense."

Giving the politicians the benefit of the doubt (I know - extremely generous), they want to do the right thing! 

But we have to start focusing our resources and research in more intelligent ways, at least for the immediate future while we deal with the emergency on hand - Global Warming.  How much public funds has been misdirected and abused by research and subsidies on schema that will never result in a significant reduction in the burning of fuels that cause global warming (look at the hydrogen fuel cell as another great example)?  At this critical time, we need to concentrate on options that at least on paper have a significant chance of a healthy EROI. 

How much time have we lost going down these dead-end roads.  After all, time is of the essence if we have any chance of effecting the outcome!

Saturday, 6 July 2013

Geothermal and Liquid Thorium Reactors - Two possible answers to Fossil Fuels.

Just a quick note regarding two promising alternative sources for generating clean energy.

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.