Researchers at US Los Alamos National Laboratory (LLNL) have confirmed a unique energy phenomena known as 'carrier multiplication' via nanoscale sized semiconductor crystals that could improve the efficiency of solar cells by squeezing more energy out of inbound photons.
Traditional solar cells absorb a photon of light that releases an electron to generate an electrical current. Any excess energy from the photon reaction is wasted as heat or vibration. The notion of 'carrier multiplciation' rests on the idea that we can get multiple electrons released from a single photon by forcing electrons into a more confined space.
Carrier multiplication was observed several years ago, but has been criticized as a phantom phenomena via a process known as 'photoionization'. But now a research team led by Victor Klimov has confirmed that semiconductor crystals designed at the nanoscale (billionth of a meter) can channel this excess photon energy into a group of tightly packed electrons, leading to a more efficient solar cell.
The team did not release statements about commercialization or scalable efficiencies. “Researchers still have a lot of work to do,” Klimov cautioned. “One important challenge is to figure out how to design a material in which the energetic cost to create an extra electron can approach the limit defined by a semiconductor band gap. Such a material could raise the fundamental power conversion limit of a solar cell from 31 percent to above 40 percent.”
Oil Supply Crunch ahead The world's leading authority on oil markets is warning that these days of cheap ($40 barrel) oil are just a mirage and that the world is likely to experience 'an oil supply crunch' next year (2010) as markets begin to recover.
Reuters reports on IEA Executive Director Nobuo Tanaka describing a potential short-term reality: "Currently the demand is very low due to the very bad economic situation, but when the economy starts growing, recovery comes again in 2010 and then onward, we may have another serious supply crunch if capital investment is not coming."
The Real Problem with Oil - No Alternative Oil's biggest problem is 'lack of substiitutability'. There is no other 'reserve' of liquid fuel that can compare to the energy locked up inside the hydrogen-carbon bonds of oil.
If we talk about using oil as gasoline for the transportation sector there is no commercially viable alternative that offers the same volume and performance. Even 'Next Generation' biofuels from algae and cellulose-eating bacteria cannot provide the scale to fill even a tiny gap in global oil production vs demand.
People who push 'solar', 'wind' or 'nuclear' (which produce electricity) as an 'alternative to oil' simply do not understand the combustion engine. You cannot put electricity inside your gas tank. We must either produce massive amounts of liquid fuel substitutes, or take a bolder step to kill the combustion engine.
Is the world ready to confront the real problem? The Combustion Engine
The most disruptive energy technologies of the 21st century might not exist today. They must be imagined and built.
Researchers are still working to evolve the basic science and applied engineering capacity to deliver low carbon solutions that can meet a doubling of global demand in the next three decades.
Bio-Synthetic Hybrids One area of cutting edge research deals with the integration of naturally occurring (or patterned) biocomponents into synthetic systems used in devices like solar cells and fuel cells.
The vision is to build hybrids that blend what 'nature has perfected' at the molecular scale, with human engineering designs at an industrial scale.
While modern solar cells struggle for low cost efficiency, plants and microbes have figured out a way to capture sunlight and store it as chemical energy at almost near perfect molecular efficiency where each photon causes the release of one electron. How? Because the parts in the photo-receptor systems fit perfectly. Researchers are now looking to create bio-hybrid systems that could inspire new forms of solar collectors.
Japanese researchers have now developed a new process to capture light energy with nearly equal efficiency by creating a synthetic molecular wire "plug" that transfers electrons from a biological photosynthetic system to a gold electrode. (Details here!) There are no details about efficiency rates or how this system could scale, but it is a promising step forward!
President Obama is close to naming the ‘Car Czar’ who will oversee a large portion of the federal auto loans and consult on the looming transformation of the US auto industry. Let's hope this person doesn't try to build a better buggy whip.
Most ideas out on the table are incremental (e.g. ‘better mileage’), or short-sighted (e.g. plug in batteries?) and fail to inspire disruptive changes that reflect a 21st century version of the transportation sector.
Here are Ten Ideas for the US Car Czar:
1) Lower the US Auto Industry I.C.E. 'Manufacturing Footprint' The problem isn't oil, it's the cost complexities of building mechanical engines. Declare the Internal Combustion Engine ‘Dead’ by 2025 (When more than 50% of new vehicles will be powered by electric motors) Have automakers share combustion engine plants and suppliers during the transition.
2) Accelerate the Electricification of the World's Auto Fleet At the same time expand the US manufacturing base around the 'next' generation platform for mobility: Electric Drive systems based on high performance motors, drive by wire systems, software and various energy storage devices.
3) Explain ‘Electrification’ clearly to the public ‘Electric’ refers to the motor, not just the battery. Next generation 'electric' vehicles will integrate batteries, fuel cells and capacitors. Fuel cells produce electricity. A hydrogen powered car is an electric car. Let’s stop the confusion and battle between technologies. Cars are not iPods, and will need various systems to function. This is a multi-decade long transition. Don't pick short-term winners.
4) Go Global - Expand our ties to Asian Manufacturers & Markets Electric cars are not designed to be built as one unit, in one country. They are assembled systems of systems that can be constantly upgraded via a global value chain. The line of 'new' car vs 'old' car blurs when we shift to modular electric platforms. And all the real growth will happen outside of the US! 'Detroit' must participate in this global supply chain and be in a position to sell 21st century vehicle systems to Asian markets. (Hint: The high value auto industrial base will revolve around polymers, software and sensors, not metal frames.)
5) Software Side of Car Experience The single greatest opportunity for the next century might be the ‘software’ side of the automobile experience. Smarter vehicles embedded with sensors and ‘situation awareness’ systems, customized driving experiences based on ‘drive by wire’, and mobility services (e.g. OnStar). The US can compete in this new growth market and benefit by getting 'more flow' out of our current roadway system as we make drivers and cars smarter. (PS - Mass Transit could use some software to create service transparency)
Read on: 6) Build next generation energy systems; 7) Reinvent the Wheel; 8) Fleet only for Plug-ins; 9) Shift Revenue streams to After Market 10) New 'types' of vehicle & service
Our economy grows because it captures stored energy released from the chemical bonds in fossil fuels formed by ancient plants and microbes that became coal and oil.
Our power plants produce electricity by breaking up carbon-hydrogen chains from coal and natural gas, and our cars blow up ancient microbes that we call 'oil'.
The value of a 'fuel' is based on its hydrogen to carbon ratio. The more hydrogen, the cleaner and better the fuel.
Yes, it's confusing, but also very important for everyone to understand where we 'extract' energy from: chemical bonds.
An Era of Clean Electrons, Clean Molecules In addition to generating electricity via renewables (et al), a central piece of our 21st century energy strategy is to reduce the amount of carbon and increase the percentage of hydrogen to hydrogen bonds (e.g. 'Cleaner molecules' that store energy) that drive our economy.
One alternative to fossil fuels, is the use of biomass waste materials that contain hydrogen molecules that can be freed (via biological enzymes) to be used in fuel cells to produce electricity.
An Elegant One Pot' Solution Researchers at Virginia Tech, Oak Ridge National Laboratory (ORNL), and the University of Georgia have produced hydrogen gas by mixing 14 enzymes, one coenzyme, cellulosic materials from nonfood sources, and water heated to about 90 degrees (32 C).
The researchers' novel combination of enzymes could equal natural hydrogen fermentation, and a chemical energy output greater than the chemical energy stored in sugars – the highest hydrogen yield reported from cellulosic materials.
Bioenergy visionaries with algae and bacteria aren't the only players in town trying to corner the market on the 'future of biofuels'. We cannot forget the Chemists.
Biofuels are expanding along two paths- one is based on chemical engineering, the other on biological processes.
Chemistry vs Biology We can create biofuels by applying chemical engineering processes (e.g. ethanol via fermentation, or biodiesel via transesterfication) with high reliability and scale, but usually at a high cost.
Or we can let Mother Nature do the work. Biology taps the power of algae and bacteria that contain special enzymes that reorganize molecules into a format that can be used to make biofuels, or converted into electricity via a fuel cell.
Biology could offer lower cost and turn carbon emissions into a feedstock, but first we must overcome challenges of scaling up volume production, and the unpredictable nature of biomolecular systems.
Wisconsin Focuses on Path of Chemistry For now, chemical conversion is the more immediate opportunity and fits within the current paradigm of processing energy and materials feedstocks. And engineers are working to overcome the challenges to reduce the number of steps, and facilitate reactions at a lower temperature with non-toxic, abundant resources.
Now scientists at the University of Wisconsin-Madison have developed a two-step method to convert cellulose into a biofuel called DMF. Professor Ronald Raines and graduate student Joseph Binder highlight the two step process: First, they convert the cellulose of untreated biomass into the "platform" chemical 5-hydroxymethylfurfural (HMF) which is used in 'a variety of valuable commodity chemicals'. Generally HMF is made using processed glucose or fructose rather than raw biomass.
Step Two: Creating a New Biofuel with Gasoline Qualities
A joint study by Sandia National Laboratories and General Motors speculates that non-food crop resources (with help from corn) 'could sustainably replace nearly a third of US gasoline use by the year 2030.'
The 90 Billion Gallon Study [PDF], which focused only on starch-based and cellulosic ethanol, found that an increase to 90 billion gallons of ethanol could be sustainably achieved by 2030 within real-world economic and environmental parameters 'assuming technical and scientific progress continues at expected rates.'
The Study assumes 75 billion gallons would be ethanol made from nonfood cellulosic feedstocks and 15 billion gallons from corn-based ethanol.
The set of non-food crop resources explored include: agricultural residue, such as corn stover and wheat straw; forest residue; dedicated energy crops, including switchgrass; and short rotation woody crops, such as willow and poplar trees. Competitive pricing models include costs of producing, harvesting, storing and transporting these sources to newly built biorefineries.
Not forgetting the real problem: The Combustion Engine Tapping biological pathways to capture carbon and create usable forms of energy is a good idea. But we must not lose site of the real problem: our dependency on the combustion engine and its requirement for liquid fuels. Energy industry pundits are always quick to raise the problem with the oil market's lack of substitutability.
As long as the combustion engine lives we cannot put electrons from solar, wind or nuclear inside the gas tank. It might not be the 'end game', but next generation biofuels are the only viable substitute liquid fuels on our our horizon.
Committing Ourselves to Enabling Disruptive Science & Technologies Given the dynamics of the global energy sector we can expect that nothing is going to change quickly, but when changes do happen - they could be potentially disruptive to how we produce, store and distributed energy.
Incremental solutions are not going to solve US or Global energy and environmental challenges. We must enable disruptive science and technologies that can 'do more with less' in fundamentally new ways. While we cannot pick winners, it is clear that the cross-disciplinary nature of science at the nanoscale will be paramount in all areas of energy from making hydrocarbons cleaner, lowering the costs of renewables, scaling up next generation bioenergy solutions, managing 'smarter grids', and creating storage solutions. Maybe a new framework for research collaboration is what we need to enable the 'new energy economy'!
Becoming 'energy efficient' goes far beyond changing light bulbs. Our greatest gains will come from moving beyond today's 'combustion' energy systems that burn fuels in large power plants and under our hoods.
Central to this 'post-combustion era' strategy is the fuel cell- which converts chemical energy of hydrogen or hydrogen rich fuels (e.g. natural gas, methanol) into electrical energy. Fuel cells are modular, have no moving parts, offer higher efficiencies, lower maintenance and are ideal for distributed applications.
One of the major roadblocks has been the high costs of platinum catalysts that are peppered on fuel cell membranes (MEAs). To scale up in the decades ahead, fuel cell researchers need to find non-precious metal catalysts.
Can Carbon outperform Platinum? Now a research team from the University of Dayton has found a way to create a carbon nanotube based catalyst that might outperform platinum and dramatically drop the costs of fuel cells.
Shape helps speed up reactions The research team, led by Dr Liming Dai, synthesized carbon nanotubes using an iron base and doped nitrogen particles to change the shape (and properties) of the nanotube cathode, resulting in a faster reaction / higher efficiency.
New Scientist reports Dai's claim that "They are even better than platinum, long regarded as the best catalyst," as they avoid problems with carbon 'poisoning' that leads to lower performance.
We have written extensively on the disruptive role of nanoscale science and engineering in all energy applications (old and new), and the importance of 'shape' in determining molecular system performance in catalysis. We cannot simply extrapolate our assumptions of what is possible or impossible with carbon or hydrogen based on a microscale era of scientific knowledge.
Giving Carbon a New Image (Nanotubes, Nanoparticles & Graphene Sheets)