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Ihering Alcoforado

Biofuels: indirect land use change and climate impact - 0 views

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    "The objective of this study is to:  compile the available recent literature on ILUC emissions;  compare these emissions with the assumed gains of biofuels;  assess how ILUC changes the carbon balance of using biofuels;  formulate policies to avoid these extra emissions associated with ILUC. Trends in land use, with and without biofuels All the studies on global agricultural markets reviewed predict that new arable land will be required to meet future global demand for food and feed. Although there will be increased productivity on current arable land (intensification), food and feed demand will probably grow faster, which means that mobilization of new land is likely to occur. Biofuels produced from crops (the current mainstream practice) will add extra demand for crops like wheat, rice, maize, rapeseed and palm oil. This will increase prices for these crops (as well as for land) and lead to two impacts: intensification of agricultural production and conversion of forests and grasslands to arable land. In this report we consider the issue of indirect land use change initiated by EU biofuels policy and seek to answer the following questions:  What is the probability of biofuels policies initiating land use changes?  What greenhouse gas emissions may result from indirect land use change, expressed as a factor in the mathematical relation given above?  What technical measures can be applied and what policy measures adopted to limit or entirely mitigate indirect land use change and the associated greenhouse gas emissions? We first (Chapter 2) broadly discuss the mechanism of indirect land use change. We next discuss why there is a perception among stakeholders that there is a serious risk that EU biofuels policy will initiate indirect land use change (Chapter 3) and consider the figures cited by other studies as an indication of the magnitude the associated greenhouse gas emissions  (Chapter 4). We then broadly consid
Colin Bennett

On Board Energy Storage - Reason Automobile Engineers Chose (Choose) Fossil Fuel : CleanTechnica - 0 views

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    Batteries have to contain all of the chemicals on both sides of their energy releasing equation. The very best batteries available today can store about 0.4 MJ/kg (0.05 kw-hr/lb) including the cases and safety systems. In contrast, gasoline carries about 46 MJ/kg (5.7 kw-hrs/lb).\n\nEven with a 20% efficient IC engine, a gasoline tank stores 20 times as much energy as a battery of equal weight. As the vehicle is moving it gets rid of some of that weight. Battery powered vehicles must carry the full weight of their energy source.\n\nThe energy density difference also plays a key role in the time that it takes to put more energy back on the vehicle once a fuel load is consumed. A two minute fill-up of a 12 gallon tank puts the equivalent of 87 kilowatt-hours into the vehicle, again, taking into account the 20% thermal efficiency.\n\n87 kilowatt-hours in 2 minutes works out to 2.6 MegaWatts. Even with a 220 volt connection, that would require about 11,800 amperes of current. Just imagine the size of the electric cables for that current.\n\nThere are certainly places and applications where electric vehicles have a role, but it is worth remembering that at least five or six generations of engineers have looked very hard at trying to meet transportation needs and they keep coming back to the same fact - when you want to move a vehicle, you need power, (energy per unit time).
Colin Bennett

Underwater Wind Turbines? bioWAVE System Designed to Create Energy from Ocean Currents : CleanTechnica - 0 views

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    Picture a kelp bed on the ocean floor swaying in the current. Done? Now picture an underwater field of bioWave turbines (pictured to your left) doing the same
davidchapman

Pumping DC power to the data center | Green Tech blog - CNET News.com - 0 views

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    By using direct current, rather than drawing electricity from outlets that supply alternating current, data center managers can reduce their energy consumption by up to 40 percent, according to the company.
Colin Bennett

Rethinking wind power - 3 views

  • Over time, what resulted from these assessments was that we selected the following sources to provide commercial electricity: hydroelectric, coal, nuclear, natural gas, and oil. (Oil is by far the smallest source.) Note that each of these current sources meet ALL of the above six essential criteria — and if they don’t (like oil recently becoming more expensive), then they get replaced, by other conventional sources that do. As a result, today, and a hundred years from now, these sources can provide ALL of the electrical needs of our society — and continue to meet all six criteria. So what’s the problem? A new criteria has been recently added to the list of criteria: environmental impact — and the current number one environmental impact consideration is greenhouse gas emissions (e.g. CO2). So why has this joined the Big Six? It is a direct result of the current debate on global warming. In response to intense political pressure, governments have acquiesced to these forces to make emissions an additional criterion. Having government step in and mandate that utility companies change the principles that have been the foundation of our electrical supply system for a hundred years is disconcerting, transforming such a successful system based on a position that is not yet scientifically resolved. Furthermore, this new criteria for electrical supply sources now has taken priority over all the other six. It has, as of late, become the ONLY benchmark of importance — the other six have essentially been put aside, and are now given only lip service. In this unraveling of sensibility there is one final incredible insult to science: alternative sources of commercial electricity that claim to meet this new super-criteria (to make a consequential impact on CO2 reduction) don’t even have to prove that they actually do it! Let's look at the environmental poster child: wind power, and examine each of the six time-tested criteria, then the new one...
Colin Bennett

New device harnesses the power of slow water currents - 0 views

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    US engineers are working on a device that could harness the power of slow-moving water currents in oceans and rivers to generate electricity.
Hans De Keulenaer

Was Edison Right After All? Reconsidering DC Power - 1 views

  • Perhaps Thomas Edison was right after all. As new technology develops, it's time to ask the question: should be using direct current (DC) instead of alternating current (AC) power?
Hans De Keulenaer

More energy efficient transistors through quantum tunneling | ScienceBlog.com - 2 views

  • While TFETs don’t yet have the energy efficiency of current transistors, papers released in December 2011 by Penn State and March 2012 by Notre Dame demonstrate record improvements in tunnel transistor drive current, and more advances are expected in the coming year.
Hans De Keulenaer

Microgrids: So Much More than Backup Energy | Renewable Energy News Article - 0 views

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    A microgrid senses the quality of the power flowing through the grid. In the event of an outage, it can disconnect from the grid at a moment's notice. It can also leverage solar, wind, or stored energy to supplement a dip in the current power sup...
Hans De Keulenaer

Appliance Efficiency and Long-Run Energy Demand | Precourt Energy Efficiency Center (PEEC) | Stanford University - 1 views

  • This project will examine how people make decisions about appliance purchases and the effect that these choices have on energy demand. Currently, approximately half of U.S. greenhouse gas emissions are attributable to residential appliance use. However, consumers can reduce their long-run energy needs by replacing old appliances with ones that are more energy efficient. It is not surprising, then, that efficiency standards have been the cornerstone of U.S. energy conservation efforts to date. Unfortunately, the effect of these standards on appliance purchase behavior is not well understood. There are two primary reasons why. Current datasets lack crucial information, and even with appropriate data it is difficult to accurately model the dynamic aspect of appliance purchase behavior. This project addresses both of these issues.
Hans De Keulenaer

Right Price for Charging Electric Cars? - WSJ.com - 1 views

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    Companies that run charging stations for electric cars, many of which currently make the service free, are looking at how much they should charge in the future. See it on Scoop.it, via Sustainable Energy via scoop.it
Ihering Alcoforado

ScienceDirect - Biomass and Bioenergy : Environmental assessment of biofuels for transport and the aspects of land use Competition - 0 views

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    Early comprehensive life cycle assessments (LCA's) that compared biofuels with fossil fuels already appeared in the beginning of the eighties. Since then the public, scientific and political interest in biofuels has continuously grown and the number of biofuels and assessed parameters has increased.At the same time, the methodology for this type of assessment has improved with certain aspects of the approach having come up by and by a process which still continues today. Several issues related to the land use currently stand in the centre of expert discussions. Keywords: Environmental assessment; Biofuels; Transport; Land use assessment; Fossil fuels Article Outline 1. Objective, scope and background 2. Procedure 3. Results: comparison of biofuels and fossil fuels 3.1. Biofuels from agriculture compared to fossil fuels and against each other 3.2. Biofuels from residues compared to fossil fuels and against each other 4. Results: land use aspects 5. Conclusions and outlook 5.1. Competing land use 5.2. Competing biomass usages
Colin Bennett

Conference looks at renewable energy | Energy, Said, Renewable | Ocean Energy Council - 0 views

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    Moving offshore While all of Texas' producing wind turbines are currently on land, at least one offshore project is expected to start production in the next few years.
Colin Bennett

Clean Alternatives to Everyday Machines: On/Off/Switch? : CleanTechnica - 0 views

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    To wrap up my ode to John Henry (and a more sustainable lifestyle) I am going to cover a few more everyday household plug-ins by giving the current ON the grid offering, it's OFF the grid alternative, and weigh in on whether a switch is warranted.
Colin Bennett

American Wind Energy Association: Wind Power Trends to Watch for in 2009 - 0 views

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    New policies include: adjusting the federal production tax credit (PTC) to make it more effective in the midst of the current economic downturn and extending it for a longer term (it expires at the end of 2009); establishing a national renewable electricity standard (RES) with a target of generating at least 25% of the nation's electricity from renewables by 2025, and a near-term target of 10% by 2012 (a Washington Post poll in early December found that 84% of Americans support such a standard); legislation and initiatives to develop a high-voltage interstate transmission "highway" for renewable energy; and strong national climate change legislation.
davidchapman

Aluminum | Aluminum Industry Set to Benefit from $6.5 Billion in Stimulus Package for More Aluminum Transmission Lines - 0 views

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    In electrical applications, aluminum can do everything that copper can, but more efficiently and economically. Aluminum provides up to twice the conductivity per pound of copper (dependent on the specific alloy and application) at less than half the cost per pound (based upon current prices) for a 400% economic-efficiency advantage over copper.
Colin Bennett

Solar Energy Breakthrough at OSU - 0 views

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    The Video Learning Center explains that conventional silicon solar cells operate by reacting with photons in light and create free electrons which flow as current in a circuit. But these electrons only remain free for a very short time. The material the OSU researchers created is not only able to capture all visible light, but also to free electrons for 7 million times longer than silicon. As a result more electricity is capable of being produced than ever before.
Hans De Keulenaer

News Story | Virginia Tech News | Virginia Tech - 0 views

  • While many people want to know when the lamp will be available, many others point out that it won't actually work. The criticism is that a great deal of weight – about two tons -- would be required and current LEDs are not sufficiently efficient. Designer Clay Mouton acknowledges that the current state of the art isn't sufficient to actually build the lamp. The news release should have said: “based on future developments in LED technology."
Colin Bennett

Wind power: Europe wants to pick your brains - 0 views

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    The European Commission is currently in the process of dreaming up an offshore wind power action plan and it's put a shout out for anyone with an opinion to come forward.
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