Sunday, October 30, 2011

Alternative energy-why do we need it?

Why Do We Need Alternatives?
To answer that question, we need to start by discussing fossil fuels-what they are, where they come from, how they are used and the advantages and disadvantages of each. Within this context, the pressing need for alternatives becomes quite clear.
What are fossil fuels?
Most fossil fuels are formed from the remains of long-dead creatures and plants. Buried over the course of hundreds of millions of years, these carbon-based deposits have been converted by heat and pressure over time into such combustible substances as crude oil, coal, natural gas, oil shales and tar sands. A smaller portion of fossil fuels is the handful of other naturally occurring substances that contain carbon but do not come from organic sources.
To make more fossil fuels would require both the creation of new topsoil filled with hydrocarbons, and time-lots of time. Given estimates of current fossil fuel reserves worldwide, it's not possible we can wait out the problem, and continue our dependence on fossil fuels until new reserves are built. At current consumption rates, the reserves of oil and coal and other fossil fuels won't last hundreds of years, let alone hundreds of millions of years.
As for creating more, experts have pointed out that it can take close to five centuries to replace a single inch of topsoil as plants decay and rocks weather. Yet in the United States, at least, much of the topsoil has been disturbed by farming, leading still more experts to the disturbing conclusion that in areas once covered by prairie, the past hundred years of agriculture have caused America's "bread basket' to lose half of its topsoil as it erodes thirty times faster than it can form.
The Advantages of Fossil Fuels in Energy Production
There are many reasons why the world became dependent on fossil fuels, and continues to rely on them. For example, it has so far been relatively cost-effective in the short run to burn fossil fuels to generate electricity at strategic centralized parts of the grid and to deliver the electricity in bulk to nearby substations; these in turn deliver electricity directly to consumers. These big power plants burn gas or, less efficiently, coal. Since so much electricity can be lost over long-distance transmission, when power needs to be concentrated more in one region than another, the fuels are generally transported instead to distant power plants and burned there. Liquid fuels are particularly easy to transport.
Thus far, fossil fuels have been abundant and easily procured. Petroleum reserves worldwide are estimated at somewhere between 1 and 3.5 trillion barrels. Proven coal reserves at the end of 2005, as estimated by British, were 909,064 million tons worldwide. Coal, furthermore, is relatively cheap.
Perhaps the simplest reason why the world continues to depend on fossil fuels is that to do anything else requires change: physical, economical, and-perhaps the most difficult-psychological. The basic technology for extracting and burning fossil fuels is already in place, not only in the large power plants but at the consumer level, too. Retrofitting factories would be cost-prohibitive, but perhaps even more daunting would be replacing heating systems in every home, factory and building. Ultimately, however, the true resistance may be our nature. We humans tend to resist change in general, and in particular those changes that require us to give up longstanding traditions, alter our ways of thinking and living, and learn new information and practices after generations of being assured that everything was "fine" with the old ways.
Why Do We Need Alternatives?
If there are so many reasons to use fossil fuels, why even consider alternatives? Anyone who has paid the least bit of attention to the issue over the past few decades could probably answer that question. If nothing else, most people could come up with the first and most obvious reason: fossil fuels are not, for all practical purposes, renewable. At current rates, the world uses fossil fuels 100,000 times faster than they can form. The demand for them will far outstrip their availability in a matter of centuries-or less.
And although technology has made extracting fossil fuels easier and more cost effective in some cases than ever before, such is not always the case. As we deplete the more easily accessible oil reserves, new ones must be found and tapped into. This means locating oil rigs much farther offshore or in less accessible regions; burrowing deeper and deeper into the earth to reach coal seams or scraping off ever more layers of precious topsoil; and entering into uncertain agreements with countries and cartels with whom it may not be in our best political interests to forge such commitments.
Finally, there are human and environmental costs involved in the reliance on fossil fuels. Drilling for oil, tunneling into coalmines, transporting volatile liquids and explosive gases-all these can and have led to tragic accidents resulting in the destruction of acres of ocean, shoreline and land, killing humans as well as wildlife and plant life. Even when properly extracted and handled, fossil fuels take a toll on the atmosphere, as the combustion processes release many pollutants, including sulfur dioxide-a major component in acid rain. When another common emission, carbon dioxide, is released into the atmosphere, it contributes to the "greenhouse effect," in which the atmosphere captures and reflects back the energy radiating from the earth's surface rather than allowing it to escape back into space. Scientists agree that this has led to global warming, an incremental rise in average temperatures beyond those that could be predicted from patterns of the past. This affects everything from weather patterns to the stability of the polar ice caps.
Conclusion
Clearly, something must change. As with many complex problems, however, the solution to supplying the world's ever-growing hunger for more energy will not be as simple as abandoning all the old methods and beliefs and adopting new ones overnight. Partly this is a matter of practicality-the weaning process would take considerable investments of money, education and, most of all, time. The main reason, however, is that there is no one perfect alternative energy source. Alternative will not mean substitute.
What needs to change?
It seems simplistic to say that what really needs to change is our attitude, but in fact the basis of a sound energy plan does come down to the inescapable fact that we must change our way of thinking about the issue. In the old paradigm, we sought ways to provide massive amounts of power and distribute it to the end users, knowing that while much would be lost in the transmission, the advantages would be great as well: power plants could be located away from residential areas, fuels could be delivered to central locations, and for consumers, the obvious bonus was convenience. For the most part our only personal connection with the process would be calling the providers of heating fuel and electricity, and pulling up to the pumps at the gas station. And the only time we would think about the problem would be when prices rose noticeably, or the power went out.
There are people who have tried to convince us that there is no problem, and that those tree-hugging Chicken Littles who talk about renewable and alternative energy want us all to go back to nature. More often than not these skeptics' motivations for perpetuating this myth falls into one of two categories: one, they fear what they don't understand and are resistant to being told what to do, or two, they have some political or financial stake in enabling our fossil-fuel addiction. (And sometimes both.)
The reality is that except for altering our ways of thinking, there will not be one major change but a great many smaller ones. A comprehensive and successful energy plan will necessarily include these things:
Supplementing the energy produced at existing power plants with alternative energy means, and converting some of those plants to operate on different "feedstock" (fuels) Shifting away from complete reliance on a few concentrated energy production facilities to adding many new and alternative sources, some feeding into the existing "grid" and some of supplying local or even individual needs Providing practical, economical and convenient ways for consumers-residences, commercial users, everyone-to adapt and adopt new technologies to provide for some or all of their own energy needs Learning ways in which we can use less energy now ("reduce, reuse, recycle"), using advances in technology as well as simple changes in human behavior to reduce consumption without requiring people to make major compromises or sacrifices

Saturday, October 29, 2011

The Big Question: Can vertical farms end food shortage?


 vertical farmsvertical farms to meet the shortage of food in the future
Why are we asking this now?
The world has seen the problem of population explosion in the last few decades like never before. With this, comes the turn to deal with several other nuisances like where to accommodate the ever increasing populace, from where to find employment for most of them and most important, from where to feed such a huge numerical, keeping in mind that most of the forest and agricultural area is slowly being converted into residential area? The remaining plots and scratches of agricultural land are turning barren, increasing the concern regarding food supply. Naturally, there has to be a way out! The only visible path right now is to go for vertical farming just like we went for vertical expansion of architecture to accommodate the increasing population.
Is it really that serious?
Well, of course, it is. Just imagine how would it be if farms were grown inside buildings and a part of your office construction would be devoted towards growing crops? In addition to reducing space required for farming, this would also partially solve the problem of urban pollution. Everything would go hand in hand. It is estimated that by 2020, the world population would increase by another three billion, naturally the place required to grow crops which would sufficiently feed the population would also be huge. An estimate is that an area 20 percent larger than the present country of Brazil would be required to attend to the cause. So you see? The issue is damn serious and so it its proposed solution.
What others are saying?
The supporters of this proposition are many. One of the strongest among them is Dickson Despommier, Professor and researcher at the Columbia University. He is strongly of the opinion that while the remaining patches of agricultural land are being squeezed to yield the maximum using artificial fertilisers and unhealthy farming practices, there has to be a way which would stop this. Vertical farming is the only possible solution. Given the benefit of doubt of problems like from where to get sunlight for a vertically overlapping pattern of agriculture and the frequent infe3station by pests, the idea is a bright one and deserves to be given a serious thought. Another supporter is Gene Giacomelli who is the director at the Controlled Environment Agricultural Programme. Along with collaborators, Gene has successfully completed a project which involved growing vegetable and fruits in a building in the Amundsen-Scott research centre in Antarctica.
The developments
1. Columbia University vertical farm


 Columbia University vertical farmColumbia University vertical farm
This is only a concept and as yet, has not been even tested out on a pilot scale. However, the estimation is that vegetation consuming a vertical area equivalent to an eighteen storied building would be enough to feed a population of fifty thousand. The one thing that has not been considered in this model is where to rear livestock, if at all horizontal farming is taken over by vertical farming? Cows and pigs cannot be kept straying on an eighty storied building to fill in their shares of fodder. Work and thought regarding this aspect is also on the move. The possibility is, sooner than later, you would possibly come across a building green with vegetation in your very in city, let’s not forget the bleating and lowing cattle.
2. Chris Jacobs’ vertical farm



 Chris Jacobs' Vertical FarmChris Jacobs' Vertical Farm
Chris Jacobs, an architect by profession and an otherwise easy to take on person, by chance involved himself in the green movement of designing vertical farms. In fact, he has been the first person ever to have designed a workable architecture of a true vertical farm. His proposed vertical farming architecture would be a tower with different floors dedicated to different crops and livestock. Energy would be an obvious problem, which he feels could be easily overcome by further research and efforts in this direction. The principle that underlies this idea is that of hydroponics or the technique to raise crops wholly in water rich in micro and macro nutrients without the slightest traces of soil particles.
The main hurdles
Every new introduction has to face questions. Similar is the case here. The first challenge is to answer how sunlight is going to penetrate the different floors so as to supply the desired wavelengths of light? This would require artificial sources of light. And if at all artificial sources are used, how exactly is this proposition green? The next question is whether the actualisation of this concept at all possible or not. The main reason is, temperature, light and nutrient conditions will have to be critically maintained to get a profitable yield of crops.
What can be done?
Steps are being taken and answers being found out to these questions. However difficult the explanation might seem to be, the conclusion is just one this proposition will have to turn to reality some day because the expanding world population would have nothing else to live on if this practice is not used. The future is called so because it is unknown. Let’s wait and see how this whole concept is given strong grounds to exist and thrive!

View the original article here