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Chapter - Energy

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It's not easy being green: Ivanpah solar plant near Nevada burns a lot of natural gas, making it a greenhouse gas emitter under state law. A solar power plant at the center of the Obama administration’s push to reduce America’s carbon footprint has its own carbon pollution problem. The administration’s initiative, which uses millions of taxpayer dollars to promote green energy, has been a boon for the Ivanpah plant in the Mojave Desert. But Ivanpah uses natural gas as a supplementary fuel, and data from the California Energy Commission show the plant burned enough of it in 2014 – its first year of operation – to emit more than 46,000 metric tons of carbon dioxide.

That’s nearly twice the pollution threshold at which power plants and factories in California are required to participate in the state’s cap-and-trade program to reduce carbon emissions. The same amount of natural gas burned at a conventional power plant would have produced enough electricity to meet the annual needs of 17,000 California homes – roughly a quarter of the Ivanpah plant’s total electricity projection for 2014. The U.S.

Gas Limitations Plant and U.S. The World's Largest Solar Plant Started Creating Electricity Today. Ivanpah Solar Power Facility. The Ivanpah Solar Electric Generating System is a concentrated solar thermal plant in the California Mojave Desert, 64 km (40 miles) southwest of Las Vegas, with a gross capacity of 392 megawatts (MW).[5] It deploys 173,500 heliostats, each with two mirrors, focusing solar energy on boilers located on three centralized solar power towers.[5] Unit 1 of the project was connected to the grid in September 2013 in an initial sync testing.[6] The facility formally opened on February 13, 2014,[1] and it is currently the world's largest solar thermal power station.[7][8] The project was developed by BrightSource Energy and Bechtel.[9] It cost $2.2 billion; the largest investor in the project is NRG Energy, a power generating company based in Princeton, New Jersey, that has contributed $300 million.

Google has contributed $168 million.;[10] the U.S. government provided a $1.6 billion loan guarantee,[11] and the plant is built on public land. Description[edit] Awards[edit] Power towers[edit] Greenbiz. À 27 ans, elle fonde HOP pour dire « Halte à l’Obsolescence Programmée » ! | AnnabelleBaudin. C’est sur Twitter que je découvre HOP *, l’association créée par Laetitia Vasseur dont l’objectif est de lutter contre l’obsolescence programmée.

Je décide d’aller à la rencontre de cette actrice du changement dont la démarche m’interpelle. Laetitia me parle de son engagement avec enthousiasme et de ce monde où tout est à réinventer. Rencontre ! Lorsqu’elle définit son métier, son message est limpide : « À l’heure où nos matières premières se raréfient, et où il est de plus en plus difficile et coûteux de les extraire, HOP propose des alternatives positives afin de mettre un terme à cette stratégie économique et commerciale qui n’a plus de sens. » Composée de juristes et d’experts en économie sociale, l’association souhaite sensibiliser le plus grand nombre de personnes au phénomène d’obsolescence programmée. Aujourd’hui, cette pratique nous condamne à des modes de consommation polluant à l’excès et surexploitant les ressources naturelles.

Laetitia est déterminée. Bonus des optimistes: The Alternative Energy Matrix. 4 views this month; 0 overall Breathe, Neo. I’ve been running a marathon lately to cover all the major players that may provide viable alternatives to fossil fuels this century. Even though I have not exhausted all possibilities, or covered each topic exhaustively, I am exhausted. So in this post, I will provide a recap of all the schemes discussed thus far, in matrix form. Then Do the Math will shift its focus to more of the “what next” part of the message. The primary “mission” of late has been to sort possible future energy resources into boxes labeled “abundant,” “potent” (able to support something like a quarter of our present demand if fully developed), and “niche,” which is a polite way to say puny. In the process, I have clarified in my mind that a significant contributor to my concerns about future energy scarcity is not the simple quantitative scorecard.

For example, it does not much matter that Titan has enormous pools of methane unprotected by any army (that we know of!). Cassandra's Legacy: How much for the sustainable energy transition? A "back of the envelope" calculation. Image source. "Back of the Envelope" calculations are a tradition in science and often turn out to be able to provide plenty of useful information, at the same time avoiding the common pitfall of complex models, that of being able to fit anything provided that one has enough adjustable parameters. The world's economy can be seen as a giant heat engine. It consumes energy, mainly in the form of fossil fuels, and uses it to produce services and goods.

No matter how fine-tuned and efficient the engine is, it still needs energy to run. So, if we want to do the big switch that we call the "energy transition" from fossil fuels to renewables, we can't rely just on efficiency and on energy saving. We need to feed the big beast with something it can run on, energy produced by renewable sources such as photovoltaics (PV) and wind in the form of electric power. Let's start: first of all, the average power generation worldwide is estimated as around 18 TW in terms of primary energy. Cassandra's Legacy: But what's the REAL energy return of photovoltaic energy? Some time ago, a colleague of mine told me the story of when he had been in charge of the installation of one of the first photovoltaic plants in Italy, in 1984 (shown in the figure, on the right).

He told me that, shortly after the installation, a high-ranking politician came to visit the plant. As a demonstration, my colleague connected the plant output to an electric heater, lighting up the internal heating elements. The politician refused to believe that the heater was being powered by the PV plant. "There has to be a trick," he said, "this is not possible.

It must be a scam. " My colleague tried to describe to him how PV cells work, but imagine trying to explain quantum mechanics to a politician! More than 30 years have passed from the installation of that old plant, but the general attitude about photovoltaic energy doesn't seem to have changed a lot. Indeed, most of the current discussions on photovoltaic energy seem to turn around one or another kind of legend. MIT, Friday, Jan. Text and Slides of the 45 min keynote lecture entitled: World energy consumption and resources: an outlook for the rest of the century (and the role of thermodynamic research) delivered by Gian Paolo Beretta, Università di Brescia, Italy, on Tuesday, Nov.4, 2008, 6:00pm, at the ASME Congress in Boston, sponsored by the Advanced Energy Systems Division. Click here for a printable PDF version. Greetings This initial slide sets the unit of measure of energy that is best suited for the purposes of our discussion today: the ton of oil equivalent.

The outline of the talk is as follows. I will then discuss the role of thermodynamics research, and I will conclude with some provocative statements to spark up the discussion. Let's start with the global energy consumption over the last 160 years. In this chart, which refers to year 2005, nations are divided into 10 groups homogeneous by type of economy, industrial development and intensity of energy consumption.

We will pass from 6 to 11 billion people. Forget Energy Efficiency, Think Exergy. If we want to understand how to wring more efficiency out of our energy usage, we need to redefine energy use in the first place, argues a new study from the American Council for an Energy-Efficient Economy. Instead of thinking about energy overall, it is better to think about high-quality energy, or exergy, according to Skip Laitner, a visiting fellow at ACEEE. “What most people call energy, for example, is what physicists and engineers are more likely to call exergy, or high-quality energy that is available to do work,” he explains in a blog post.

“Energy that is either wasted or useless -- in effect, energy that has no capacity to perform work such as the heat in the atmosphere -- is referred to as anergy.” Add up anergy and exergy and you get total energy. Laitner found that just tracking energy commodities, for instance, accounted for only 80 percent of the exergy necessary to power the U.S. economy in 2010. Essentially, Laitner wants everyone to think bigger. Thinking Big About Energy Efficiency | ACEEE. Observers of U.S. energy policy might think of energy efficiency as a useful investment strategy to smartly manage the growth of energy consumption. They might also see it as a cost-effective means to ease our transition into a post-carbon world. And yes, the evidence does support both of these notions. But there is also emerging evidence that demonstrates that energy—and especially the more efficient use of that energy—plays a much more critical role within the economic process than is generally understood.

Building on the work of a number of noted economists and physicists, the new ACEEE report, Linking Energy Efficiency to Economic Productivity: Recommendations for Improving the Robustness of the U.S. Economy, explores the productive use of energy as it affects the robustness of the larger U.S. economy. Current Levels of Inefficiency Constrain a More Robust Economy The U.S. economy is not especially energy efficient. Conversion Efficiency—Total Exergy to Useful Work. Education Archives - Page 2 of 3 - Waste To Energy SystemsWaste To Energy Systems | Page 2. 1. OysterBreakThe world is your oyster. At least it is for Tyler Ortego, Matt Campbell, and two professors at Louisiana State University, who invented the OysterBreak system in 2005 and brought coastal protection to life, literally. The system, which is essentially a chain of huge linked concrete cylinders, is made of an oyster-growing substrate that, once installed, is colonized by oyster larvae and eventually grows into a living reef.

Because these solid reefs grow faster than sea levels rise, they reduce shoreline erosion. ORA Estuaries, the company that Ortego founded in 2010 to run the building and distribution of the oyster reefs, recently won The Big Idea pitch competition at the 2015 New Orleans Entrepreneur Week. 2. 3. 4. 5. IEA Sankey Diagram. European Energy Flows Sankey. Energie. , quelles sont leurs performances, leurs impacts environnementaux et économiques et leur perspectives de développement ? La recherche et développement, moteur d’une évolution technologique accélérée, notamment dans les domaines du photo-voltaique, de la biomasse et des moyens de stockage de l’énergie deviennent tout autant important que les capacités d’investissement et de déploiement. Le Développement Durable donne jour à une , bousculant les choix politiques et géopolitiques, les projections de rentabilité économique, l’analyse de l’impact environnemental et le déploiement et l’intégration de ces nouveau systèmes au réseau énergétique existant.

Nous assistons à une évolution extrêmement rapide de certaines technologies (photovoltaïque, biologie, nanotechnologie, électronique, …) mais également à une remise en question de l’intégration de toutes ces technologies. Accéder à la MindMap (carte heuristique) interactive des énergies renouvelables: Energie fossile – Pétrole – Charbon – Gaz. L’Acier. La fabrication d’acier remonte loin dans l’histoire de l’humanité. Cette technologie se heurte alors au problème de la suppression des impuretés (carbones, silicium et manganèse), problème résolu en 1855 par le soufflage d’air (puis oxygène pur) dans le métal en fusion afin d’éliminer ces éléments.

Le processus de fabrication de l’acier nécessite essentiellement les ressources suivantes ; minerais de fer, charbon, coke (obtenu par pyrolyse anaérobique de la houille), gaz et électricité. Le fer n’existe pas à l’état pur dans la nature mais sous forme d’oxydes de fer qu’il est nécessaire de “réduire”, c’est à dire lui oter ses atomes d’oxygène. Le diagramme Sankey suivant montre les flux de transformation de l’acier, de sa production à sa consommation. Le diagramme montre que le secteur le plus gourmand dans l’utilisation de l’acier est le bâtiment. Il montre aussi la faible part de recyclage à partir des produits finis. Retour à la section “Matériaux à fort impact environnemental”