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Undamming the rivers: Solar farms are super efficient new and clean sources of Energy September 17, 2015

Posted by OromianEconomist in Energy Economics.
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???????????Yale environment 360

“From Britain to the Czech Republic, European nations have been restoring rivers to their natural state — taking down dams, removing levees, and reviving floodplains. For a continent that long viewed rivers as little more than shipping canals and sewers, it is a striking change.”

Undamming Rivers: A Chance
For New Clean Energy Source

John Waldman and Karin Limburg, Environment 360, 6 August 2015

Many hydroelectric dams produce modest amounts of power yet do enormous damage to rivers and fish populations. Why not take down these aging structures, build solar farms in the drained reservoirs, and restore the natural ecology of the rivers?

Hydroelectric power is often touted as clean energy, but this claim is true only in the narrow sense of not causing air pollution. In many places, such as the U.S. East Coast, hydroelectric dams have damaged the ecological integrity of nearly every major river and have decimated runs of migratory fish.

This need not continue. Our rivers can be liberated from their concrete shackles, while also continuing to produce electricity at the site of former hydropower dams. How might that occur? A confluence of factors — the aging of many dams, the advent of industrial-scale alternative energy sources, and increasing recognition of the failure of traditional engineering approaches to sustain migratory fish populations — raises fresh possibilities for large rivers to continue to help provide power and, simultaneously, to have their biological legacies restored.

The answer may lie in “sharing” our dammed rivers, and the concept is straightforward. Remove aging hydroelectric dams, many of which produce relatively small amounts of electricity and are soon up for relicensing. When waters recede, rivers will occupy only part of the newly exposed reservoir bottoms. Let’s use these as a home for utility-scale solar and wind power installations, and let’s employ the existing power line infrastructure to the dams to connect the new solar and wind power facilities to the grid. This vision both keeps the electricity flowing from these former hydropower sites, while helping to resurrect once-abundant fish runs, as has recently happened in Maine….

Read more at:-

https://e360.yale.edu/feature/undamming_rivers_a_chance_for_new_clean_energy_source/2901/

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Africa Progress Panel: WORLDS APART Range of time Viewed from Africa, energy use patterns in rich countries represent another universe June 26, 2015

Posted by OromianEconomist in Africa, Alternative Energy, Energy Economics.
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O

Africa Progress Panel

Affordable and reliable electricity underpins every aspect of social and economic life. But Sub-Saharan Africa has an energy crisis that demands urgent political attention. Two in every three Africans, around 621 million in total, have no access to electricity at all.

Ethiopia, with a population of 94 million, consumes one-third of the electricity supplied to the 600,000 residents of Washington D.C. Greater London consumes more electricity than any country in Africa other than South Africa. By international standards much of Africa’s energy infrastructure is dilapidated, reflecting several decades of under-investment. According to the IEA, the average efficiency of Sub-Saharan Africa’s gas-fired power plants is around 38 per cent. Similarly, most of Africa’s coal-fired power plants employ sub-critical technologies, rather than the super-critical technologies that could generate far more electricity from the same amount of fuel. Recent super-critical coal-fired power plants built in China generate on average 30 per cent more electricity than those operating in Africa. Economic growth has intensified pressure on Africa’s creaking energy infrastructure. One symptom of that pressure is a boom in leasing of emergency power. Unable to meet base-load demand through the grid, governments are turning to high-cost energy providers using technologies designed to meet emergency needs. Low levels of power generation are both a symptom and a cause of wider development challenges. In part, Africa’s limited power generation is the product of low average incomes. But it is also a contributory factor in keeping incomes low. In that context, the widening energy gap between Africa and other regions is a matter of concern. There is a very real sense in which today’s inequalities in energy are tomorrow’s inequalities in economic growth, international trade and investment.

DISCONNECTED AFRICA APP_REPORT_2015

Energy Consumption, disconnected Africa6Energy Consumption, disconnected Africa2Energy Consumption, disconnected Africa3Energy Consumption, disconnected Africa4Energy Consumption, disconnected Africa5Energy Consumption, disconnected Africa

Unreliable power supply has created a buoyant market in diesel-powered generators. Around 40 per cent of businesses in Tanzania and Ethiopia operate their own generators, rising to over 50 per cent in Kenya.15 In Nigeria, around four in every five SMEs install their own generators.16 On average, electricity provided through diesel-fuelled back-up generators costs four times as much as power from grid.17 Diesel fuel is a significant cost for enterprises across Africa, even in less energy-intensive sectors such as finance and banking. According to McKinsey, diesel fuel represents around 60 per cent of operator network costs for mobile-phone operators.18 High cost and unreliable supply add to the cost of doing business in Africa, with damaging consequences for economic growth, investment and tax revenues. The World Bank has estimated the losses at 2-4 per cent of GDP.19 Lack of reliable and cost-effective electricity is among the top constraints to expansion in the manufacturing sector in nearly every Sub-Saharan country.20 Small and medium enterprises account for most of the job creation but face particularly severe problems, with around half citing the high cost and unreliability of supply as a barrier to enterprise development. Lack of electricity reinforces the poverty trap Restricted access to electricity has direct and damaging consequences for household poverty. Africa’s poor typically pay higher unit costs for energy than the rich. This is partly because the rich are subsidized, but also because the poor use inefficient energy sources including batteries, candles, and charcoal.If the poor could use more efficient energy sources they could reduce the share of income that they spend on energy and free up resources for other priority areas. It could also reduce the amount of time that women and girls spend collecting firewood and cooking. Households across Africa, including very poor households, spend a significant share of their income on energy. Data from 30 countries showed that the average share of household spending directed to energy was 13 per cent.21 The poorest households typically spend a larger share of their income on energy than richer households. In Uganda, the poorest one-fifth allocated 16 per cent of their income to energy, three times the share of their richest counterparts. Women and girls spend a lot of time collecting firewood and cooking with inefficient stoves. Factoring in the costs of this unpaid labour greatly inflates the economic costs that come with Africa’s energy deficits. Estimates by the World Bank put the losses for 2010 at US$38 billion or 3 per cent of GDP.

DISCONNECTED AFRICA APP_REPORT_2015

Food Insecurity: Biofuels Are Not a Green Alternative to Fossil Fuels February 10, 2015

Posted by OromianEconomist in African Poor, Agriculture, Alternative Energy, Biofuels, Development Studies, Energy Economics.
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OBiofuela are not green

     

 

Biofuels Are Not a Green Alternative to Fossil Fuels

by Andrew Streer* and Craig Hanson**

Powering cars with corn and burning wood to make electricity might seem like a way to lessen dependence on fossil fuels and help solve the climate crisis. But although some forms of bioenergy can play a helpful role, dedicating land specifically for generating bioenergy is unwise. It uses land needed for food production and carbon storage, it requires large areas to generate just a small amount of fuel, and it won’t typically cut greenhouse gas emissions.

First, dedicating areas to bioenergy production increases competition for land.

Roughly three-quarters of the world’s vegetated land is already being used to meet people’s need for food and forest products, and that demand is expected to rise by 70 percent or more by 2050. Much of the rest contains natural ecosystems that keep climate-warming carbon out of the atmosphere, protect freshwater supplies, and preserve biodiversity.

Because land and the plants growing on it are already generating these benefits, diverting land—even degraded, under-utilised areas—to bioenergy means sacrificing much-needed food, timber, and carbon storage.

Second, bioenergy production is an inefficient use of land.

While photosynthesis may do a great job of converting the sun’s rays into food, it is an inefficient way to turn solar radiation into non-food energy that people can use. Thus, it takes a lot of land (and water) to yield a small amount of fuel from plants. In a new working paper, WRI calculates that providing just 10 percent of the world’s liquid transportation fuel in the year 2050 would require nearly 30 percent of all the energy in a year’s worth of crops the world produces today.

The push for bioenergy extends beyond transportation fuels to the harvest of trees and other sources of biomass for electricity and heat generation. Some research suggests that bioenergy could meet 20 percent of the world’s total annual energy demand by 2050. Yet doing so would require an amount of plants equal to all the world’s current crop harvests, plant residues, timber, and grass consumed by livestock–a true non-starter.

Third, bioenergy that makes dedicated use of land does not generally cut greenhouse gas emissions.

Burning biomass, whether directly as wood or in the form of ethanol or biodiesel, emits carbon dioxide just like burning fossil fuels. In fact, burning biomass directly emits a bit more carbon dioxide than fossil fuels for the same amount of generated energy. But most calculations claiming that bioenergy reduces greenhouse gas emissions relative to burning fossil fuels do not include the carbon dioxide released when biomass is burned. They exclude it based on the assumption that this release of carbon dioxide is matched and implicitly offset by the carbon dioxide absorbed by the plants growing the biomass.

Yet if those plants were going to grow anyway, simply diverting them to bioenergy does not remove any additional carbon from the atmosphere and therefore does not offset the emissions from burning that biomass. Furthermore, when natural forests are felled to generate bioenergy or to replace the farm fields that were diverted to growing biofuels, greenhouse gas emissions go up.

That said, some forms of bioenergy do not increase competition with food or land, and using them instead of fossil fuels could reduce greenhouse gas emissions. One example is biomass grown in excess of what would have grown without the demand for bioenergy, such as winter cover crops for energy. Others include timber processing wastes, urban waste wood, landfill methane, and modest amounts of agriculture residues.

Using so-called second-generation technologies to convert material such as crop residues into bioenergy has a role to play and avoids competition for land. A challenge will be to do this at scale, since most of these residues are already used for animal feed or needed for soil fertility, and others are expensive to harvest.

There are good alternatives to bioenergy made from dedicated land. For example, solar photovoltaic (PV) cells convert sunlight directly into energy that people can use, much like bioenergy, but with greater efficiency and less water use. On three-quarters of the world’s land, solar PV systems today can generate more than 100 times the usable energy per hectare as bioenergy. Because electric motors can be two to three times more efficient than internal combustion engines, solar PV can result in 200 to 300 times as much usable energy per hectare for vehicle transport compared to bioenergy.

One of the great challenges of our generation is how the world can sustainably feed a population expected to reach 9.6 billion by 2050. Using crops or land for biofuels competes with food production, making this goal even more difficult.

The world’s land is a finite resource. As Earth becomes more crowded, fertile land and the plants it supports become ever more valuable for food, timber and carbon storage—things for which we don’t have an alternative source.

*Dr Steer is president of the WRI. **Hanson is the WRI’s global director of food, forest and water programmes

 

This blog post was originally published in The Guardian on January 29, 2015.

Source:

http://www.wri.org/blog/2015/01/biofuels-are-not-green-alternative-fossil-fuels?utm_medium=wri-page&utm_source=facebook.com&utm_campaign=socialmedia

Read related at:

http://biofuel.org.uk/threat-to-food-supply.html

 

Related:

WRI’s Searchinger says land and crops should not be used for bioenergy production, biofuels not curbing climate change.

http://www.eenews.net/tv/2015/02/10

http://www.eenews.net/tv/videos/1937/transcript