Posts Tagged ‘energy research’
Nanotechnology from an Industrial Ecology Perspective
Posted by: Karl Ramjohn
There has been much discussion in recent times of the possible impacts on health and the environment, associated with the emerging field of nanotechnology, for example:
> Nanotechnology Not That Green
> Nanotechnology’s Public Health Hazard
> Nano-pollution: the next scare story?
The following research paper provides a substance-flow analysis (SFA) of carbon nano-tubes from an industrial ecology perspective
Lekas, D. 2005. Analysis of Nanotechnology from an Industrial Ecology Perspective Part II: Substance Flow Analysis of Carbon Nanotubes. Yale School of Forestry & Environmental Studies. November 2005; 22 pp.
Link to full paper —> http://www.nanotechproject.org/file_…ed%20part2.pdf
1. Introduction
The “next plastic,” the future for electronics, a new energy storage material. Such descriptors have been given to the nanomaterial carbon nanotubes. These carbon atom cylinders with diameters under 100 nanometers are quickly becoming the focus of significant research and production around the world. Many people estimate that we will see high penetration of carbon nanotubes into everyday products in the near future. At the same time, however, many have expressed concern over the potential health risks from exposure to nanotubes. In order to better understand the scope of nanotube production, use, and destiny, particularly in terms of their impacts in the environment and on human health, this paper presents findings from an investigation into the feasibility of performing a substance flow analysis on carbon nanotubes.
A substance flow analysis (SFA) is a study of the flow of specific materials throughout the economy from cradle to grave. This approach has been called “a tool for analyzing the societal metabolism of substances,”. It examines and attempts to quantify the inputs of a substance or material into production, end-use applications, and ultimately end-of-life phases. Insight into the material inputs and outputs and other detail at one level or stage (e.g., production) may influence findings at other levels.
A SFA can be an appropriate tool when the material of interest is linked to a particular impact and thus warrants a more focused analysis on the “stocks and flows” and “concentrations in the environment,”. Because of the potential environmental and health impacts of carbon nanotubes (pending their penetration into products and uses), I hypothesized that the SFA approach would help shed light on the uncertain impacts. More specifically, I suspected that information on the quantity of carbon nanotubes produced would better inform understanding on the application of these substances into end uses, and that end-use information would improve the understanding of potential consequences of carbon nanotubes to users and in the environment.
2. Methodology
3. Nanotube Overview
4. Carbon Nanotube SFA Findings
5. Conclusions
Recent News on Energy and the Environment 26.10.08
Posted by: Karl Ramjohn
Some recent articles featured on the Energy Environment News Portal, on current and emerging issues related to energy and the environment
> Australia: Financial Crisis takes toll on Carbon Scheme
> Additive to make tallow-based biofuel more viable
> Secrets From Within Planets Pave Way For Cleaner Energy
> Nanotechnology – Not That Green?
Magma Energy – Feasible since 1982 !?
Submitted by: Karl Ramjohn
MAGMA ENERGY
This is a report that was published in 1982, representing research from the late 1970’s – i.e. during the previous “energy crisis” when the elevated oil prices had created much interest in the field of alternative / renewable energy (like in the present). This is one of the many initiatives that seems to have been forgotten when the oil prices crashed in the mid-80’s, but it is very interesting to read from the perspective of our present circumstances…
John L. Colp. 1982. Final Report – Magma Energy Research Project. Sandia National Laboratories, U.S. Department of Energy; 42 pp.
Link to report: Information Bridge: DOE Scientific and Technical Information – Sponsored by OSTI
ABSTRACT
- The DOE-funded, 7-yr research project conducted by Sandia National Laboratories to assess the scientific feasibility of extracting energy directly from buried magma sources in the upper 10 km of the earth’s crust have been completed successfully.
- Two methods of generating gaseous fuels in the high-temperature magmatic environment – generation of hydrogen by the interaction of water with ferrous iron, and hydrogen, methane and carbon monoxide generation by the conversion of water-biomass mixtures – have been investigated and show promise.
- Scientific feasibility (the demonstration, by means of theoretical calculations and supporting laboratory and field measurements, that there are no known insurmountable theoretical or physical barriers which invalidate a concept or process) was demonstrated for the concept of magma energy extraction.
- The US magma resource is estimated at 50,000 to 500,000 quads of energy – a 700- to 7,000 year supply at the current US total energy use rate of 75 quads per year.
- Existing geophysical exploration systems are believed to be capable of locating and defining magma bodies and were demonstrated over a known shallow buried molten-rock body. Drilling rigs that can drill to the depths required to tap magma are currently available and experimental boreholes were drilled into buried molten rock at temperatures up to 1100 °C.
- Engineering materials compatible with the buried magma environment are available and their performances were demonstrated in analog laboratory experiments
- Studies show that energy can be extracted at attractive rates from magma resources in all petrologic compositions and physical configurations.
- Downhole heat extraction equipment was designed, built and demonstrated successfully in buried molten rock and in the very hot margins surrounding it.
- Two methods of generating gaseous fuels in the high temperature magmatic environment – generation of hydrogen by the interaction of water with ferrous iron, and hydrogen, methane and carbon monoxide generation by the conversion of water-biomass mixtures – have been investigated and show promise.
Related:
http://cr4.globalspec.com/thread/25305/Magma-Energy-Feasible-since-1982
Biomass Energy – Sustainable Solution to Livestock Wastes?
Submitted by: Karl Ramjohn
Livestock production is an important food supply and economic activity, the primary goal of which is to supply high-quality protein (meat, eggs, dairy products, etc) for the needs of human populations. The animals serve as concentrated sources of typically dispersed nutrients. Subsidiary products may include leather, fertilizers, inputs to animal feeds, and energy sources (biofuels). The challenge of sustainable livestock production systems is to promote food security in a manner which is economically viable and socially acceptable without causing land degradation or irreversibly affecting ecological resilience. As such, sustainability must promote a favourable cost – benefit ratio, and as far as possible avoid reducing the set of options available to future generations. This has very significant social considerations, as seemingly obvious solutions may be difficult to implement, as they may be biologically but not economically sustainable.
The recycling of materials, and thus minimizing the generation of wastes is a basic process which must be implemented to meet the demands of sustainability in developed and developing countries alike. Systems which utilize energy produced from biomass are examples of energy-recycling systems. All biomass originates through carbon dioxide fixation by photosynthesis. Consequently, biomass utilization may be regarded as a critical component of the global carbon cycle of the biosphere.
Most biomass cannot be directly utilized, and must undergo some sort of transformation before being converted to fuel. Biological processes for the conversion of biomass to fuels include ethanol fermentation by yeast or bacteria, and methane production by microbial consortia under anaerobic conditions. Unlike ethanol fermentation, anaerobic digestion for methane production utilizes organic materials containing carbohydrates, lipids and proteins. Waste materials from livestock production are applicable to anaerobic digestion, with the added advantage of reducing environmental impacts, such as unpleasant odours and water pollution.
Methane fermentation is therefore a versatile biotechnology, which can convert almost all types of polymeric materials to methane and carbon dioxide under anaerobic conditions. It converts the waste products of livestock systems into useful products of commercial value, while reducing the environmental costs associated with other methods of livestock waste disposal. As such, it offers an effective means of pollution reduction, superior to that achieved by conventional aerobic processes. It is also an efficient method of converting unused biomass resources (crop residues, forestry, industrial/municipal and livestock wastes) into biofuels and fertilizers.
The digested slurry (by-product of methane production) retains the nitrogen and other mineral nutrients which are lost when biomass wastes are directly burned, while reducing BOD/COD. Methane is a principal constituent of natural gas, and extraction of this resource from livestock waste is a small-scale but useful method of supplementing extraction from geologic deposits. It also mitigates the problems associated with slow decomposition on the land surface, in the context of the large “greenhouse effect” of methane – up to 25 times that of carbon dioxide. The pathogens are also destroyed, reducing the health effects of the digested biomass, which also does not attract flies or rodents.
Biomass conversion is economically feasible within the constraints of scale and location. The main problems associated with biomass digestors is the relatively high price of implementation, the fact that the technology is still somewhat experimental, and the high standard of management and maintenance required.
Overriding issues in the future of biological energy systems are the overall efficiency of converting biomass to fuels, the economics of such processes, their environmental impacts, their competitiveness with thermochemical processes for biomass, and their compatibility with evolving economic and political structures.
Related:
http://tropicalenv.conforums.com/index.cgi?board=landuse04&action=display&num=1218573241
Algae – The Solution to Energy Crisis & Climate Change?
From: World Business Council for Sustainable Development (WBCSD): AFP – July 10, 2008
As the world mulls over the conundrum of how to satisfy a seemingly endless appetite for energy and still slash greenhouse gas emissions, researchers have stumbled upon an unexpected hero: algae. So-called microalgae hold enormous potential when it comes to reining in both climate change, since they naturally absorb large amounts of carbon dioxide, as well as energy production, since they can easily be converted to a range of different fuel types.
“This is certainly one of the most promising and revolutionary leads in the fight against climate change and the quest to satisfy energy needs,” Frederic Hauge, who heads up the Norwegian environmental group Bellona, told AFP. The idea is to divert exhaust spewed from carbon burning plants and other factories into so-called “photobioreactors”, or large transparent tubes filled with algae. When the gas is mixed with water and injected into the tubes, the algae soak up much of the carbon dioxide, or CO2, in accordance with the principle of photosynthesis. The pioneering technique, called solar biofuels, is one of a panoply of novel methods aiming to crack the problem of providing energy but without the carbon pollution of costly fossil fuels — with oil pushing 140 dollars a barrel and supplies dwindling — or the waste and danger of nuclear power.
Studies are underway worldwide, from academia in Australia, Germany and the US, to the US Department of Energy, oil giant Royal Dutch Shell and US aircraft maker Boeing. This week alone, Japanese auto parts maker Denso Corp., a key supplier to the Toyota group, said it too would start investigating, to see if algae could absorb CO2 from its factories. The prestigious Massachusetts Institute of Technology (MIT), for one, has successfully tested the system, finding that once filtered through the algae broth, fumes from a cogeneration plant came out 50-85 percent lighter on CO2 and contained 85 percent less of another potent greenhouse gas, nitrogen oxide. Once the microalgae are removed from the tubes they can easily be buried or injected into the seabed, and thus hold captive the climate changing gases they ingest indefinitely. And when algae grown out in the open are used in biomass plants, the method can actually produce “carbon negative” energy, meaning the energy production actually drains CO2 from the atmosphere. This is possible since the microalgae first absorbs CO2 as it grows and, although the gas is released again when the biomass burns, the capturing system keeps it from re-entering the air. “Whether you are watching TV, vacuuming the house, or driving your electric car to visit friends and family, you would be removing CO2 from the atmosphere,” Hauge said.
Instead of being stored away, the algae can also be crushed and used as feedstock for biodiesel fuel — something that could help the airline industry among others to improve its environmental credentials. In fact, even the algae residue remaining after the plants are pressed into biodiesel could be put to good use as mineral-rich fertiliser, Hauge said “You kill three birds with one stone. The algae serves at once to filter out CO2 at industrial sites, to produce energy and for agriculture,” he pointed out. Compared with the increasingly controversial first-generation biofuels made from food crops like sunflowers, rapeseed, wheat and corn, microalgae have the huge advantage of not encroaching on agricultural land or affecting farm prices, and can be grown whenever there’s sunlight. They also can yield far more oil than other oleaginous plants grown on land. “To cover US fuel needs with biodiesel extracted from the most efficient terrestrial plant, palm oil, it would be necessary to use 48 percent of the country’s farmland,” according to a recent study by the Oslo-based Centre for International Climate and Environmental Research. “The United States could potentially replace all of its petrol-based automobile fuel by farming microalgae on a surface corresponding to five percent of the country’s farmland,” the study added.
As attractive as it may seem however, the algae solution remains squarely in the conception phase, with researchers scrambling to figure out how to scale up the system to an industrial level. Shell, for one, acknowledged on its website some “significant hurdles must be overcome before algae-based biofuel can be produced cost-effectively,” especially the large amounts of water needed for the process. In addition, further work is needed to identify which species of algae is the most effective.
Further discussions related to the topic of this post:
http://www.oilgae.com/forum/viewforum.php?f=1
http://www.worldofrenewables.com/showthread.php?t=16547
http://www.its2hot.in/viewtopic.php?f=28&t=158
http://www.sustainabilityforum.com/forum/climate-change/2762-algae-solution-climate-change.html
“Spatial Footprint” Challenges of Solar Energy Use
Submitted by: Karl Ramjohn
Solar energy can be utilized in either passive or active systems. Passive systems do not contain any internal energy sources, and can be used for direct heating (e.g. solar dryers, water heaters, etc.) or day-time lighting (e.g. “green” office buildings). Photovoltaic devices are an example of active systems based on semiconductor technology, often using silicon (an indirect semiconductor).
The advantages of using solar radiation are well established and often cited – such as their ability (with proper design) to lower energy costs, reduce emissions and other environmental pollution, thereby initiating the process of competitively replacing hydrocarbon use, and thus contributing to sustainable development.
Solar energy approaches are also frequently suggested as a sustainable solution in less-developed countries in the tropical environment, on the assumption of having less seasonal variation in day-length and more hours of direct sunlight each day (i.e., usually a higher intensity and longer duration of incident solar radiation each day). The fuel medium (solar radiation) is also an “open-access” resource (no direct user cost). The overall decline in the operational costs seen over the past 35+ years is also typically acknowledged.
However, one major challenge remains with regard to conversion to solar energy use – their spatial footprint (land use requirement) in the event that larger scale utilization is proven feasible. In particular, for the use of flat-plate collectors or PV systems in tropical environments, this becomes an issue.
The primary reason is that to optimize the use of solar radiation, the panels (or plates) need to be sloped so as to correspond to the latitude of the specific area of the Earth, hence taking up more horizontal space in the tropics. If we take the example of an island in the middle-tropics such Trinidad & Tobago, implementation will require the slope of the panels to be 10 degrees (corresponding to latitude) for the same technology that may be placed at an angle of 40 degrees in countries within temperate regions. The implication is that the area set aside for power generation (or other solar energy use) will no longer be available for other land uses (such as agriculture) and this may be a significant limiting factor, especially in the case of small-island developing states. After all, any large-scale conversion will require much more than a rooftop, and island geography often restricts the feasibility of wind energy.
Some recent discussions aimed at solving or mitigating these potential challenges to sustainable energy:
http://cr4.globalspec.com/thread/20329
GEO ENERGY NETWORK 