March 12, 2008

Food-CSA


The Problem with Food:
Did you know that food travels and average of 1300 miles before it reaches the grocery shelves? In addition, for each dollar you spend on produce, only 10 percent of the money returns to the farmer. The other 90% of your money goes to pay for the food transportation, packaging, and marketing.

Top 12 reasons to buy locally:
1) Freshness. Locally-grown organic fruits and vegetables are usually harvested within 24 hours of being purchased by the consumer.
2) Taste. Produce picked and eaten at the height of freshness tastes better.
3) Nutrition. Nutritional value declines, often dramatically, as time passes after harvest. Locally-grown produce is freshest, it is more nutritionally complete.
4) Purity. Eighty percent of American adults say they are concerned about the safety of the food they eat. They worry about residues of pesticides and fungicides. These materials are not permitted in an organic production system either before or after harvest.
5) Regional Economic Health. Buying locally grown food keeps money within the community. This contributes to the health of all sectors of the local economy, increasing the local quality of life.
6) Variety. Organic farmers selling locally are not limited to the few varieties that are bred for long distance shipping, high yields, and shelf life. Often they raise and sell wonderful unusual varieties you will never find on supermarket shelves.
7) Soil Stewardship. Soil health is essential for the survival of our species. Conventional farming practices are rapidly depleting topsoil fertility. Creating and sustaining soil fertility is the major objective for organic growers.
8) Energy Conservation. Buying locally grown organic foods decreases dependence on petroleum, a non- renewable energy source. One fifth of all petroleum now used in the United States is used in Agriculture. Organic production systems do not rely upon the input of petroleum derived fertilizers and pesticides and thus save energy at the farm. Buying from local producers conserves additional energy at the distribution level.
9) Environmental Protection. Soil erosion; pesticide contamination of soil, air, and water; nitrate loading of waterways and wells; and elimination of planetary biodiversity are some of the problems associated with today's predominate farming methods. Organic growers use practices that protect soil, air, and water resources; and that promote biodiversity.
10) Cost. Conventional food processes don't reflect the hidden costs of the environmental, health and social consequences of predominate production practices- of, for instance, correcting a water supply polluted by agricultural runoff, or obtaining medical treatment for pesticide induced illness suffered by farmers or consumers. When these and other hidden costs are taken into account, as they should be, locally grown organic foods are seen clearly for the value they are, even if they cost a few pennies more.
11) A Step Toward Regional Food Self Reliance. Dependency on far away food sources leaves a region vulnerable to supply disruptions, and removes any real accountability of producer to consumer. Regional food production systems keep the food supply in the hands of many, providing interesting job and self-employment opportunities, and enabling people to influence how their food is grown.
12) Passing on the Stewardship Ethic. When you buy locally produced organic food you cannot help but raise the consciousness of your friends and family about how food buying decisions can make a difference in your life and the life of your community; and about how this basic act is connected to planetary issues.

What is Community Supported Agriculture (CSA):
CSA is a strategy to connect local farmers with local consumers. People make a financial commitment to a farm, and they become shareholders or members of that community, in return they recieve fresh produce every week. Most people pay at the beginning of the season, prices usually range from $300-$600 for 20 weeks of fresh produce. This mutually supportive relationship between local farmers and local consumers, creates economically stable farm operation, in which members are assured the highest quality produce often below retail prices. In return, farmers and growers are guaranteed a reliable market for a diverse selection of crops.

Food-Problem Statement

A startling change is unfolding in the world’s food markets. Soaring fuel prices have altered the equation for growing food and transporting it across the globe. Huge demand for biofuels has created tension between using land to produce fuel and using it for food.

A growing middle class in the developing world is demanding more protein, from pork and hamburgers to chicken and ice cream. And all this is happening even as global climate change may be starting to make it harder to grow food in some of the places best equipped to do so, like Australia.

Kaith Bradsher
A New Global Oil Quandary: Costly Fuel Means Costly Calories
New York Times, 01.19.2008

March 11, 2008

Energy - Large Scale Solar Farms




Sarah Sandman

How Solar Power Works
Converting Photons to Electrons


howthingswork.com

"The solar cells that you see on calculators and satellites are photovoltaic cells or modules (modules are simply a group of cells electrically connected and packaged in one frame). Photovoltaics, as the word implies (photo = light, voltaic = electricity), convert sunlight directly into electricity. Once used almost exclusively in space, photovoltaics are used more and more in less exotic ways. They could even power your house. How do these devices work?

Photovoltaic (PV) cells are made of special materials called semiconductors such as silicon, which is currently the most commonly used. Basically, when light strikes the cell, a certain portion of it is absorbed within the semiconductor material. This means that the energy of the absorbed light is transferred to the semiconductor. The energy knocks electrons loose, allowing them to flow freely. PV cells also all have one or more electric fields that act to force electrons freed by light absorption to flow in a certain direction. This flow of electrons is a current, and by placing metal contacts on the top and bottom of the PV cell, we can draw that current off to use externally. For example, the current can power a calculator. This current, together with the cell’s voltage (which is a result of its built-in electric field or fields), defines the power (or wattage) that the solar cell can produce."

What are Photovoltaic Power Plants?


howthingswork.com

"Photovoltaic power plants - Solar modules are nowadays parts of large standalone or grid-connected systems. Large photovoltaic power plants (MW range) have beeing constructed in Germany, Spain, USA, Italy, Netherlands etc. Worldwide more than 250 large PV power plants with peak power 1 MWp or more (each plant) are connected to the public grid(s)."



Worldwide Photovoltaic Power Plant Breakdown

solarserver.de

"80% of all large photovoltaic plants (power related) are installed in Europe (700 MWp). The share of the USA accounts about 16 % (142 MWp) and in Asia 4 % (34 MWp) are installed. At present Germany hosts nearly 50 % of the world’s installed photovoltaic power, but its market share was decreasing slowly within the last months.

The most dynamic market is Spain - where an extreme increase of installed power has been observed in 2007. In the last decade only the USA and Germany created a steady growth of their photovoltaic market. The fast growth in Spain started about three years ago and led to an extreme increase in 2007. Further progress is visible in Europe and in South Korea. Italy, particulate France, and Greece turn out to be auspicious markets. The rest of the world (i.e. Africa, South America and Australia) represents less than 1 % of global installed PV power but shows significant potentials for future solar energy use in these regions.


Countries with cumulative installed power more than 1 MW of large photovoltaic power plants (> 200 kWp each considered plant) are listed in Table 2 a the end of this report. Germany leads with more than 400 MW, followed by Spain (almost 250 MW) that displaced the USA (140 MW) at the second position. Italy and Japan (each about 17 MW) Korea (13 MW) and Portugal (12 MW) anyhow reached two digit figures. Countries with less than 1 MWp installed are Thailand, France (without overseas territories), United Kingdom, Malaysia, Saudi Arabia, Luxembourg, Rwanda, India and Mexico.

Primary PV world markets are still Germany with about 45 % of the installed power, followed by Spain (28 %) and the USA with 16 % market share. Spain proved as the most dynamic PV market with an impressive growth that might be probably lower this year. The average installed capacity of a single large commercial power plant has increased from 400 kWp in 1997 to 1,64 MWp in 2007. The average capacity of sole commercial PV plants accounts for 1,14 MWp."

Parque Solar Hoya de Los Vincentes
Jumilla, Spain


http://technology4life.wordpress.com

January 31, 2008

"With an installed peak power of 20 MW, the solar park at Jumilla, Murcia (Southeastern Spain) is the world’s current highest capacity PV plant and the most efficient to-date.

It took a team of 400 people 11 months to build the Jumilla plant, where 120,000 solar panels are grouped into 200 separate photovoltaic arrays -owned by different investors- to convert light from the sun into electricity. It’s expected to generate an estimated annual income of $28 million (€19 million) and a reduction in CO2 emissions of 42,000 tons a year.
jumilla_solar_farm.jpg

The plant covers an area of 100 hectares in La Hoya de Vicentes, Jumilla, (see picture) where the local Mayor says 300 days of sun a year are guaranteed. Its total annual production will be the equivalent of the energy used by 20,000 homes.

Different measures were taken following the recommendations from a local association, Juncellus, to ensure high environmental criteria in the construction of the plant. They included replanting an area of almost 5.4 thousand square yards around the plant, water deposits for fires, drinking troughs for birds and other such details."

Solarpark Waldpolenz
Brandis, Germany


renewableenergyworld.com

February 23, 2007

"Construction on a 40 megawatt (MW) solar generation power plant is under way at a former military base in the Saxon region of Germany. The total surface area of the planned photovoltaic (PV) installation? It’s comparable to about 200 soccer fields, said Matthias Willenbacher, cofounder and CEO of the juwi group.

The “Waldpolenz” solar park -- which is being developed by the juwi group in the township of Brandis -- will be comprised of approximately 550,000 First Solar thin-film modules. The direct current produced in the solar modules will be converted into alternating current and fed completely into the power grid.

Once completed in 2009, the project will be one of the largest photovoltaic projects ever constructed. Currently the biggest PV plant in the world has an output capacity of around 12 megawatts."

With a specific price of approximately Euro 3,250 per kilowatt [U.S. $4,226], the power plant is expected to be around 20%-40% cheaper than the going German market price. In addition, after just a year in operation, the “Waldpolenz” will have produced the energy needed to build it.


Stirling Energy and SoCal Edison
Mojave Desert : Victorville, CA


wikipedia.org

February 2, 2008

Stirling Energy is a United States company which develops equipment for utility-scale renewable energy power plants and distributed electrical generating systems. In California’s Mojave Desert, already home to 354 megawatts of SEGS solar thermal facilities, Stirling Energy Systems in conjunction with utility company Southern California Edison is erecting a 500 megawatt, 4,600-acre (19 km²), solar power plant to open in 2009. [1]

According to their website, Stirling Energy Systems (SES) is a systems integration and project management company that is developing equipment for utility-scale renewable energy power plants and distributed electric generating systems (“gensets”). Stirling Energy stands to rake in upwards of $90 million a year once the solar dishes are generating 500 MW in 2011. For SCE, already the largest purchaser of renewable energy in the U.S., the extra 500 MW will more than double the 354 MW of solar power it tapped in 2004 from nine other solar-thermal operations in the Mojave. It will also add almost 20% to SCE’s 2,588 MW of renewable energy sources, including 1,021 MW of wind power. Last year more than 18% of the electricity that the utility delivered to its customers came from renewables.

China’s Solar Projected Future
Dunhuang, China


redherring.com

November 20, 2006

In the latest sign that solar projects are growing larger, China announced plans Tuesday to build the world’s largest solar power plant in Dunhuang, a city in the northwestern Gansu province.

The plant, which will take five years to build, will yield 100 megawatts of peak capacity and will cost an estimated 6.03 billion yuan (about $766 million), according to the state-run Xinhua news agency.

That’s small compared to conventional coal-fired plants, which generally have capacities in the “hundreds of megawatts, if not a thousand megawatts,” said Joel Serface, director of the Austin Clean Energy Incubator.

But it’s large for solar, and it’s only one of several projects claiming to become “the world’s largest,” rapidly growing the world’s solar energy capacity.

Still, the latest announcement is significant news because China could potentially become one of the “world’s largest markets” for solar power, said David Saltman, chief executive of solar company Open Energy.


sources:

howthingswork.com

redherring.com
solarservice.de
wikipedia.org
renewableenergyworld.com
technology4life.wordpress.com

Energy-Off Grid


What is off grid?
Off grid technologies allow for private homes and people to access
Environmentally friendly methods of attaining power independently from public power sources.

The benefit of off grid power is that it can decrease or rid customers of a power bill, allowing the consumer to make more environmentally conscious decisions about the source of their power (if local power companies are not already doing so).
Some states, such as California give large rebates and cash back to private individuals that utilize off grid technology. If you connect home-generated power to the grid, you can add power back to the grid, running your meter backwards, potentially making a bit of money (though this is usually minimal).


What are the Options?


Solar
Due to the price of solar power systems, solar power is most common in off grid applications. There are two types solar energy systems: solar thermal systems collect radiant energy to produce heat; photovoltaic-cell systems convert direct sunlight into a stream of electrons to produce energy.

Photovoltaics are the most common form of off grid home generated power. Many homeowners are proud to have solar panels bolted to their roofs, but those who want solar power without the bolt on look can now use building integrated photovoltaics. Most of these are solar shingles, which are intended to cover your roof like shingles. Most of these shingles tend to be between 10-20 percent efficient. Though photovoltaics have been around since the 1970’s, new materials have allowed them to be produced in a myriad of ways allowing them to be used in a variety of ways from building materials, to components on new gadgets. Also, the modular setup of solar power means it is easy to expand on existing solar projects.

Wind
Wind is generally considered the cleanest alternative energy source, and is beginning to scale down for home use (though it tends to be more practical in rural environments than urban ones). A small wind turbine is enough to offset a good portion of electricity in a typical home, and best of all can be easily retrofitted to existing homes.

Anew breed of vertical axis wind turbine (VAWT) from Helix Wind offers a promising design that may change the way we do wind at home. The Helix Wind Savonious 2.0 uses a unique rotor capable of capturing omni-directional winds to provide quieter, kinder small wind power for your urban home.

Water
Have a small stream or creek on your property? Waterwheels have been used around the world for centuries to mill grain and de-hull rice. Now some of these wheels are being retrofitted with generators to provide electricity, too. In some places, entirely new systems are being installed, these systems are called micro-hydro systems, because they are generally capable of powering only a few houses or a small village and they can be plopped down in a river without significantly affecting its flow, banks or general ecosystem as a large hydroelectric dam would.

Geo-Thermal
Ground-source heat pumps use the earth or groundwater as a heat source in winter and a heat sink in summer. Using resource temperatures of 4°C (40°F) to 38°C (100°F), the heat pump, a device which moves heat from one place to another, transfers heat from the soil to the house in winter and from the house to the soil in summer.
Geothermal heat pumps can be used almost worldwide. The earth's temperature a few feet below the ground surface is relatively constant everywhere in the world, while the air temperature can change from summer to winter extremes. Unlike other kinds of geothermal heat, shallow ground temperatures are not dependent upon tectonic plate activity or other unique geologic processes. Thus geothermal heat pumps can be used to help heat and cool homes anywhere.


Fuel Cell
Fuel cell technology can be used to make electricity to power vehicles, homes, and businesses. Unlike conventional technologies, fuel is not burned but is combined in a chemical process. A fuel cell consists of two electrodes sandwiched around an electrolyte. Oxygen passes over one electrode and hydrogen over the other, generating electricity, water, and heat.

The problem with fuel cells is that the hydrogen utilized to power the cells must be initially produced by a primary energy source. The idea is, if you use a renewable energy source as the main source of hydrogen, a fuel cell can be considered a renewable energy source. It is more efficient to just use the renewable energy source from the start though, making hydrogen a bit impractical at the moment.

Eco Futurists still promote hydrogen as the replacement for fossil fuels. Many are banking on common green algae that excrete hydrogen when deprived of certain nutrients. Scientists are currently working on making the algae more productive at producing the hydrogen in a lab setting.

Synopsis
Essentially, solar is the best option for residential, off grid technology. While wind has the potential to be very effective, most residential environments do not work well with wind due to scale logistics (unless you live way out in the country). Hydrogen fuel cells look great for the future of energy production, but the technology is not yet there today to make it truly sustainable

Sources
http://www.consumerenergycenter.org/renewables
http://www.gosolarcalifronia.ca.gov
http://www.geothermal.org
http://www.helixwind.com






March 10, 2008

Energy - SunEdison


Introduction
:

SunEdison in the largest solar energy provider in North America, helping commercial, governmental organizations and utility providers establish and maintain a solar unit. Holding long-term relationships with trusted suppliers and manufacturers, SunEdison is reliable. Due to the complex financing elements needed to make it solar energy a viable solution, SunEdison is also a service agent, helping customers manage and install solar units’ specific to their needs and location. In each case SunEdison will analyze, design, manage materials, construct, certify, activate, monitor and maintain a unit. With customers such as Whole Foods and Staples, SunEdison is showing that solar power is as much of a positive environmental move and an economic investment.


Commercial and Government

Setting up and maintaining a solar unite is simplified for the customer for Sun Edison will do the work and only ask the company to pay for the solar energy produced; no upfront capital is required. It makes it an easy choice for it is predictable and straightforward. While the unite is in use, SunEdison will continue with monitoring and service where a customer login page is created for the company to see detailed information on their personal energy system and production.

Commercial/Kohls: Leading by Example

Kohls is serving a leader in using solar power as a long term solution. In September, the first of 63 roof top electrical systems was activated at the Laguna Niguel location in California. The company is conscious of government goals, where the 25 MW that will be produced by the total of this endeavor will be a large step toward the California Solar Initiative’s goal of 3,000 MW by 2017. Kohl’s has been recognized with their high rankings on both the EPA’s Top 10 Retain List and Fortune 500 Green Power Challenge.

Government/Department of Energy: Recognizing the Potential

The U.S. Department of Energy (DOE) has called upon SunEdison to develop a solar energy unit at the DOE’s National Renewable Energy Laboratory (NREL) in Colorado. Expected to be completed by May 2008, the project is a large venture, however toped with great benefits. The project is one of the two largest projects at the NREL; five-acres of solar panels will be used to generate 750kW of clean power, which is expected to power seven percent of the facilities needs.

“We commend NREL for its progress in providing clean, renewable energy”

-Thomas Rainwater, CEO of SunEdison


Utility

Energy utility providers are feeling pressure from customers and the Renewable Portfolio Standards to provide a certain amount of solar energy. From building to maintaining, SunEdison makes it simple. Furthermore, SunEdison will also help the utility providers with delivering solar energy to utility’s customers as well as create a system to develop Solar Tariffs.

Xcel Energy: Throwing the Big Switch

SunEdison made it easy. So easy that this solar plant, the largest of its kind, was activated in December of 2007 before its completion date. SunEdison made this possible by financing and building the plant in addition to guaranteeing maintenance. As a significant power provider in Colorado, this project highlights the state’s renewable energy commitment. However, this venture is not only a benefit to the environment, but the community as well, where it is expected to create new jobs and create energy independence/ Colorado Governer Bill Ritter calls it a “win-win for everyone.”

Energy- Solar Edison

Website:

www.solaredisonllc.com

Introduction:

Solar Edison is about practical, economic, and sustainable energy. The company creates renewable energy systems for residential and commercial use in New England, which can be configured either on or off the grid. Representing solar panel and PV component manufactures, Solar Edison is able to resourcefully supply the customer with a system that will eliminate an electric bill and carbon emissions.

The Solar Power System by Solar Edison is an affordable solution for the supply of electricity. Due to its novelty, the company is committed to helping design as well as installs the system. Furthermore, there are a number of benefits for using solar electricity, where Solar Edison is committed to helping the customer by assisting them to obtain rebates and tax incentives.

They are also dealers of a number of products including ZAP! Electric Cars, Trucks, and ATVs, as well as renewable energy products.

Commercial Use

A grid tied system is used, which is economical because it reduced energy bills, earns utility rebates of up to $2.50 per installed watt, qualifies for tax credit, and is exempt from state sales tax. In the first year, approximately 75% of the capital cost is earned back in the first year and the remaining in following four years.

Residential Use

This system is beneficial for residential use for it is economic, environmentally conscious, and recognized as a means to earn state and federal rebate as well as tax incentives. Through using this system, a customer’s energy bill is reduced or eliminated; it is also sustained for it fixes the cost of electricity over 20 years and avoids increases in utility rates. The customer can also sleep at night for the energy source is pollution free, reducing the world’s CO2 emissions. The three most common solar systems for residents are a Grid-Tie PV System, Off-Grid/Stand Alone System, or Grid-Tie/Battery Back Up.

Products

Solar Edison sells a range of products for renewable energy including Photovoltaic Solar Panels, Fronius Inverters, Crown Deep Cycle Batteries, and ZAP! Electric Cars, which are electric or solar-electric hybrids.

My Analyses

When reading about Solar Edison, it seems so logical and I wonder why more people are not adapting this system. I am impressed by the company’s initiative concerning renewable energy and their emphasis on its economic benefits.

Energy- There is No Such Thing as Clean Coal


Coal is the most abundant fossil fuel today, accounting for more than 80% of all recoverable fossil fuels. In addition, coal is relatively cheap compared to the perpetual climb of oil and natural gas prices. However, these advantages are completely superficial. The environmental costs of coal apply to every stage of converting coal to energy, making the coal fuel cycle one of the most devastating activities for the environment.


Coal Production:

- The largest coal resources are held by the United States, followed by Russia, China, India, and Australia. U.S. recoverable coal resources of 270 billion tons are about 250 times current annual production, while China’s recoverable resources of 190 billion tons are about 80 times its current annual production.

- The United States produces more than 1 billion tons of coal each year

- More than 40 percent of U.S. coal production comes from federal public lands, primarily in the West, and this production has increased by 20 percent in the last five years. In 2005 more than 453,000 acres of federal land were under coal leases, and the U.S. Bureau of Land Management (BLM) sold the rights to mine 1 billion tons of coal on this land.

-Almost 90 percent of western coal production is from surface mining, which accounts for nearly all of Wyoming’s production.

- About 65 percent of Appalachian production is from underground mining, whereas about 60 percent of Interior production is from surface mining.

- China produced more than 2.3 billion tons of coal in 2006, nearly 40 percent of the world’s total and more than the United States, Russia, and India combined.

- More than 95 percent of China’s coal comes from underground mines, often with a high sulfur and ash content. China’s coal mining industry employs more than 7.8 million people in around 25,000mines

Coal use:

-Coal-fired electricity generation has increased by 24% between 1990 and 2004

-In 2004, the use of coal resulted in 2.6 billion metric tons of heat trapping carbon dioxide (CO2) emissions in China and 3.9 billion metric tons of CO2 in the United States, adding up to more than 20 percent of global CO2 emissions from fossil fuel combustion.

- In China, more than half of the coal supply is used to generate electricity, with the rest used primarily for production of steel, cement, and chemicals, as well as for domestic heating and cooking.

- About half of the U.S. electricity supply is generated using coal-fired power plants.

- More than 90 percent of the U.S. coal supply is used to generate electricity in some 600 coal fired power plants scattered around the country, with the remainder used for process heat in steel manufacturing and other heavy industrial production. Coal is used for power production in coal-fired power. Texas uses more coal than any other state, followed by Indiana, Illinois, Ohio, and Pennsylvania.


Environmental Effects of Coal Production:


Health and Safety Risks:

- Coal mining industry about five times as hazardous as the average private workplace (fatality rate of .23 per thousand workers)

- 22 fatalities in 2005, 47 fatalities in 2006 (2,518 fatalities in 1925)

- Coal miners suffer many nonfatal injuries are are vulnerable to serious diseases (most notably black lung disease)

- China’s coal mining industry is the most dangerous in the world. Although it produced nearly 40 percent of the world’s coal in 2005, it reported 80 percent of the total deaths in coal mine accidents. With soaring demand for coal in China, mine operators often ignore safety standards in search of quick profits. Other factors include inadequate safety equipment and a lack of safety education among miners. In 2006, 4,746 coal mining deaths were reported, occurring due to coal mine floods, cave-ins, fires, and explosions, resulting in an average of 13 coal miner deaths a day

- Some scholars indicate that, including unreported deaths, coal mining in China could result in closer to 20,000 deaths a year.25 In addition, about 300,000 coal miners suffer from black lung disease in China, with 5,000 to 8,000 new cases arising each year

Destruction of Terrestrial Habitats:

- Coal mining—and particularly surface or strip mining—poses one of the most significant threats to terrestrial habitats in the United States. The Appalachian region, for example, which produces more than 35 percent of our nation’s coal, is one of the most biologically diverse forested regions in the country. But surface mining activity clearcuts trees and fragments habitat, destroying natural areas that were home to hundreds of unique species of plants, invertebrates, salamanders, mussels, and fish.

- Surface mining activities cause severe environmental damage as huge machines strip, rip apart, and scrape aside vegetation, soils, and wildlife habitat as they drastically—and permanently—reshape existing land forms and the affected area’s ecology to reach the subsurface coal. Strip mining replaces precious open space with invasive industrialization that displaces wildlife, increases soil erosion, takes away recreational opportunities, degrades the wilderness, and destroys the region’s scenic beauty. Forty-six western national parks are located within 10 miles of an identified coal basin, and these parks could be significantly damaged by future surface mining in the
region.

Water Pollution:

- Coal mining of all types can also lead to increased sedimentation, which affects water chemistry and stream flow and negatively impacts aquatic habitat. Valley fills in the eastern United States and waste rock from strip mines in the West add sediment to streams, as do the construction and use of roads in mining complexes. A final physical impact of mining on water involves the hydrology of aquifers. MTR and valley fills remove upper drainage basins and often connect two previously separate aquifers, altering the surrounding groundwater recharge scheme.

- Chemical pollution produced by coal mining operations comes most significantly in the form of acid mine drainage (AMD). In both underground and surface mining, sulfur-bearing minerals common in coal mining areas are brought up to the surface in waste rock. This problem could be exacerbated to the extent that advanced sulfur dioxide pollution controls allow increased use of high‑sulfur coal. When these minerals come in contact with precipitation and groundwater, an acidic leachate is formed. This leachate picks up heavy metals and carries these toxins into streams or groundwater. Waters affected by AMD often exhibit increased levels of sulfate, total dissolved solids, calcium, selenium, magnesium, manganese, conductivity, acidity, sodium, and nitrate, reflecting drastic changes in stream and groundwater chemistry. The degraded water becomes less habitable, non potable, and unfit for recreational purposes

- In the eastern United States, AMD has damaged an estimated 4,000 to 11,000 miles of streams. In the West, estimates are between 5,000 and 10,000 miles of streams polluted.

Air Pollution:

- There are two main sources of air pollution during the coal production process. The first is methane emissions from the mines. Methane is a powerful heat-trapping gas and is the second most significant contributor to global warming after carbon dioxide. According to the most recent official inventory of U.S. global warming emissions, coal mining results in the release of 3 million metric tons of methane per year, which is equivalent to 68 million metric tons of carbon dioxide.

- The second significant form of air pollution from coal mining is particulate matter (PM) emissions. While methane emissions are largely from eastern underground mines, PM emissions are particularly serious at western surface mines. Mining operations in the arid, open, and frequently windy region creates a significant amount of particulate matter. These wind-driven dust emissions occur during nearly every phase of coal strip mining in the West, but the most significant sources are removal of the overburden through blasting and use of draglines, truck haulage of the overburden and mined coal, road grading, and wind erosion of reclaimed areas. The diesel trucks and equipment used in mining are also a source of PM emissions.

- Particulate matter emissions are a serious health threat that can cause significant respiratory damage as well as premature death.

- 3,700,000 tons of carbon dioxide (CO2), the primary human cause of global warming--as much carbon dioxide as cutting down 161 million trees.

- 10,000 tons of sulfur dioxide (SO2), which causes acid rain that damages forests, lakes, and buildings, and forms small airborne particles that can penetrate deep into lungs.

- 500 tons of small airborne particles, which can cause chronic bronchitis, aggravated asthma, and premature death, as well as haze obstructing visibility.

- 10,200 tons of nitrogen oxide (NOx), as much as would be emitted by half a million late-model cars. NOx leads to formation of ozone (smog) which inflames the lungs, burning through lung tissue making people more susceptible to respiratory illness.

- 720 tons of carbon monoxide (CO), which causes headaches and place additional stress on people with heart disease.

- 220 tons of hydrocarbons, volatile organic compounds (VOC), which form ozone.

- 70 pounds of mercury, where just 1/70th of a teaspoon deposited on a 25-acre lake can make the fish unsafe to eat.

- 225 pounds of arsenic, which will cause cancer in one out of 100 people who drink water containing 50 parts per billion.

- 114 pounds of lead, 4 pounds of cadmium, other toxic heavy metals, and trace amounts of uranium.


Waste Generated:

-One significant waste is the sludge that is produced from washing coal. There are currently more than 700 sludge impoundments strewn throughout mining regions, and this number continues to grow. These impoundment ponds pose a potential threat to the environment and human life. If an impoundment fails, the result is disastrous.

- Waste created by a typical 500-megawatt coal plant includes more than 125,000 tons of ash and 193,000 tons of sludge from the smokestack scrubber each year. Nationally, more than 75% of this waste is disposed of in unlined, unmonitored onsite landfills and surface impoundments.

- Toxic substances in the waste -- including arsenic, mercury, chromium, and cadmium -- can contaminate drinking water supplies and damage vital human organs and the nervous system. One study found that one out of every 100 children who drink groundwater contaminated with arsenic from coal power plant wastes were at risk of developing cancer.

- Once the 2.2 billion gallons of water have cycled through the coal-fired power plant, they are released back into the lake, river, or ocean. This water is hotter (by up to 20-25° F) than the water that receives it. This "thermal pollution" can decrease fertility and increase heart rates in fish. Typically, power plants also add chlorine or other toxic chemicals to their cooling water to decrease algae growth. These chemicals are also discharged back into the environment.

- Much of the heat produced from burning coal is wasted. A typical coal power plant uses only 33-35% of the coal's heat to produce electricity. The majority of the heat is released into the atmosphere or absorbed by the cooling water.
Coal Transportation:

- A typical coal plant requires 40 railroad cars to supply 1.4 million tons in a year. That's 14,600 railroad cars a year.

- Railroad locomotives, which rely on diesel fuel, emit nearly 1 million tons of nitrogen oxide (NOx) and 52,000 tons of coarse and small particles in the United States. Coal dust blowing from coal trains contributes particulate matter to the air.

Carbon Capture and Disposal of CO2:

- The critical technology for coal is CO2 capture and geologic disposal. This is the only technology that will make continued coal use compatible with protection of the climate. Marginal improvements in coal plant efficiency will not deliver reductions on the scale needed to stabilize concentrations at reasonable levels.

- Coal-based CO2 capture and disposal system (CDS) have all been demonstrated at commercial scale in numerous projects around the world. But there is large potential for optimization of each element, and their integration, to bring down costs and improve efficiency. In addition, experience with large-scale injection of CO2 into geologic formations is still limited.


Liquid Coal:

- The considerable economic, social, and
environmental drawbacks of coal-derived liquid
fuel preclude it from being a sound option to
move America beyond oil

- Relying on liquid coal could nearly double global warming pollution per gallon of transportation fuels, and increase the devastating effects of coal mining felt by communities and ecosystems stretching from Appalachia to the Rocky mountains.

- If the CO2 from liquid coal plants is captured instead of being released into the atmosphere, then well-to-wheels CO2 emissions would be reduced some but would still be higher than emissions from today’s crude oil system


Analysis:

- The U.S is addicted to coal, and our problem is that we have way too much of it. Coal means a boost in our economy but it also means the destruction of the environment.

-Enforce and strengthen the laws that already exist (Clean Water Act, Clean Air Act, Surface Mining Laws, etc.)

-No EPA exemptions

-Making the production and use of coal a cleaner process takes a lot. A lot of money, time, and work that should be directed toward clean, more efficient, renewable energy.

-Is Carbon Capture and Disposal really the answer? Does it even work?


Sources:

www.nrdc.org
www.ucsusa.org

Energy- Galveston Offshore Wind

Galveston Offshore Wind

“The Texas Wind Rush is on, and the pioneers are staking their claims, and wherever there are pioneers, the settlers soon follow.”- Jerry Patterson, Commissioner of the Texas General Land Office

October 2, 2007- Announcement that GOW has leased 4 additional tracts of offshore space for wind tests, totaling 5 all together. This is the only offshore land lease for wind power in the US.
In May of 2007 an instrument tower was erected in 280 feet waters off the coast of Galveston Texas, to measure wind speeds, consistency, etc. This tower is expected to stay till the end of May 2008.

GOW- part of the larger company Wind Energy Systems Technology (WEST) Has leased the 4 additional tracts at competitive prices, as part of the regular oil and gas lease sale. The first tract was offered at non-competitive prices. But by leasing the tracts with oil and gas, it is bringing wind into the competitive field.

Monetary Details
The deal it that once the wind farms are operational, WEST will pay the State’s Permanent School Fund a minimum of $132 Million present day dollars (or $258 adjusted). The Permanent School fund will also receive a gross revenue from the wind farms production and with that the total rises to more than $231 Million present day dollars- or $433 Million over the 30 year lease.The research phase is expected to last 4 years, and during this time WEST is paying the PSF $91,000 per year per tract on the 4 newest acquisitions.

Following the research phase of the leases, W.E.S.T. will begin to develop wind farms on each of the four tracts. If winds are favorable, W.E.S.T. plans to build wind farms that will produce a minimum of 250 MW to 300 MW per lease.

W.E.S.T. will then begin paying the state’s Permane
nt School Fund a percentage of the electricity produced on the leases. For the first eight years of each lease, W.E.S.T. will pay the Permanent School Fund from 3.5 to 6.5 percent of all electricity produced from the four tracts of land.
Generally, that royalty will start at 3.5 percent of all e
lectricity produced for the first eight years of the lease. That percentage will grow to 4.5 to 4.75 percent of total production for years nine through 16, and 5.5 to 6.5 percent of total production for years 17 through 30 of the 30-year lease.


Construction Costs

As material and construction prices have been going up-particularly in wind turbine cases due to demand (the opposite as to what we had all hoped) many offshore projects are being put on hold. However in this case yes, the price of the turbines are going up, but the price of the oil rigs are going down, so they aren’t seeing a huge increase in the budget of the project.


Sources
http://www.glo.state.tx.us/news/archive/2007/events/windlease_100207.html

Energy- Offshore Wind

Wind Farms can be located in 3 different zones.


How do wind turbines work?


1 Rotor Blades, which are shaped like airplane wings attach to a hub and can be up to 150 feet long.
2 Pitch drive Rotates blades to reduce lift when wind speeds become too great.
3 Nacelle Encloses components.
4 Brake Acts as a backup to the pitch drive.
5 Low-Speed Shaft Attaches to the rotor.
6 Gear Box The rotor turns the low-speed shaft at speeds ranging from 20-400 rpm. Transmission gears increase the speed to the 1,200-1,800 rpm required by most generators to produce electricity.
7 High-Speed Shaft Attaches to the Generator.
8 Generator Converts energy into electricity.
9 Heat Exchanger Cools generator.
10 Controller Computer system runs tests, adjusts, turbine.
11 Anemometer Measures wind speeds.
12 Wind Vane Detects wind direction.
13 Yaw Drive Keeps rotor facing into the wind.
14 Towe

On Shore vs. Off Shore

Historically, wind power has been developed on land. But the interest has now been directed towards the sea. Particularly coastal areas with water depths of between 5 and 15 m. Here the output is up to 50% higher than on land and the visual and noise pollution is greatly reduced.

Also areas that have sufficient land for large scale wind operations such as middle America are less efficient as power supply locations as they are located far away from city centers where most of the population lives. Since 30% of all energy produced is lost in it’s transportation sighting power sources close to population hubs is key. Off shore sites tend to be closer to large cities than vast unused expanses of land.

How do Off Shore wind farms work?

Piles (1) are driven into the seabed. Erosion protection, similar to sea defenses, are placed at the base to prevent damage to the sea floor. The top of the foundation is painted a bright color to make it visible to ships and has an access platform to allow maintenance teams to dock.

The blades (2) rotate around a horizontal hub, which is connected to a shaft inside the nacelle (3). This shaft, via a gearbox, powers a generator to convert the energy into electricity. Sub sea cables (4) take the power to an offshore transformer (5) which converts the electricity to a high voltage (33kV) before running it back 5 -10 miles to connect to the grid at a substation on land (6).
http://www.bwea.com/offshore/how.html

London Array
www.londonarray.com

A proposed offshore wind farm, to be built off the Kent and Essex coasts, in the outer Thames Estuary.

A consortium called London Array Limited is developing the project. The company comprises the following three partners: Shell WindEnergy, E.ON and DONG Energy.

The project will consist of up to 341 turbines which would have a capacity of 1,000 MW of electricity. This is enough to meet the electricity needs of 750,000 homes or roughly 1/4 of the homes in the greater London area.

The project would contribute significantly to the Government’s target for renewable energy – providing around 10% of their target for 10% wind energy by2010.

The turbines will range between 3MW and 7MW in electrical capacity, depending on when they are installed. The hub heights will be between 85m and 100m above sea level, and the total turbine height won’t be greater than 175m.

The wind turbines will typically begin generating electricity at a minimum wind speed of 7mph, with full power being achieved from 29mph. They would begin to shut down at wind speeds greater than 56mph.


BUT THIS IS REALLY COOL!


Wind Energy Systems Technology (WEST)
RECYCLING ON A GRAND SCALE

http://www.wired.com/wired/archive/15.02/wind.html


Offshore oil drilling sites are being retrofitted for wind power.

Normally returned to shore only to rust, old drilling platforms, refurbished by a local startup, will return to sea for the wind. The first will carry wind-monitoring equipment as well as radar for tracking migratory birds. Those that follow will be topped by windmills.

The turbines will be tested 18-square-mile area roughly 10 miles off the coast of Galveston, Texas, where the first offshore wind farm in the US is under construction.

The project, at only $240 million and 150 megawatts of peak output—enough to power 45,000 homes— is modest. But what allows them to compete with larger more established projects is their reuse of materials. Not only are they reusing old oil industry infrastructure, but in the event of a hurricane they decided to outfit their windmills with hydraulic lifts scavenged from oil-industry machinery; the system would lower the turbines in the event of a squall.

Energy- TransGas Energy Facility


Why TransGas Energy in NYC?
In New York State, the generation of electricity is subject to a competitive market place. TGE's proposed facility is expected to be very efficient and will be well positioned to compete against and displace generation from older, less efficient generating facilities. Studies performed by municipal and state organizations forecast that New York State's and New York City's power demands are growing and more generation capacity must be built.

What it looks like:
TGE is taking extraordinary care to design its plant to be visually compatible with a modern, vibrant, urban setting. The plant design will not fit most people’s image of what a power plant or an industrial facility looks like. It will look more like a modern building than like the older power plants that currently exist in the city. We believe the architecture of this facility will redefine how power generating facilities should be designed in the future.

How it works: Waste heat from an electric power plant still contains enough heat to generate steam. Some electric generation potential is typically sacrificed in order to generate the steam but the overall effect greatly increases efficiency. When a single plant produces both electricity and steam, it is called a “cogeneration” facility. By making use of the waste heat, cogeneration systems can achieve overall efficiencies of 75% or more. The primary technological breakthrough leading to a significant jump in efficiency was the introduction of combined-cycle technology. This technology “combines” a gas turbine with a conventional steam turbine. The efficiency improvement occurs because fuel is combusted only once — in the gas turbine. The hot exhaust gases from the gas turbine are used to heat the steam needed to generate electricity in the steam turbine. Older baseload plants utilizing only steam turbines were limited in their efficiency to less than 40%. Combined-cycle systems can achieve efficiencies approaching 55%. Combined cycle technology became possible only after gas turbines were adapted for power generation in the 1970s.

What it is:
Trans Gas Energy Facility will be a 1,100-megawatt (MW) cogeneration facility on the East River between the Greenpoint and Williamsburg's North Side sections of Brooklyn. The proposed Facility will also be capable of producing up to 2 million pounds per hour (mmlbs/hr) of steam for export to Con Edison's steam distribution system in Manhattan. The proposed state-of-the art facility will convert natural gas to electricity, adding in numerous ways to the reliability in New York City’s electricity supply. It will produce energy much more efficiently and cleanly than the facilities that are currently operating in New York City. TGE also has the capability to supply steam to the Con Edison steam system. The site of the proposed installation is presently an oil storage and trucking terminal. It has served as an oil and fuel storage terminal for over 100 years. The Department of City Planning proposed in June 2003 to convert this industrial zone to parkland. In response, TGE formulated a concept for an underground design, with a park topping the site. Whether built above or below ground, the TGE plant will become an anchor facility for a new and revitalized north Brooklyn waterfront. TGE’s facility would rehabilitate an active industrial site located in a drab, pedestrian-unfriendly industrial area. TGE's underground design takes up only an acre of land and the surface, and dedicates the remainder to waterfront parkland, which can become part of a future waterfront access network.

Benefits:
Economic:
Reduced energy prices, economic stimulation, enhanced reliability
Environmental: Improved air quality, Brownfield cleanup, water savings
Social/Cultural: Innovative architecture, New York City 2012 Olympics, education of the arts
Architectural: Dynamic architecture, sustainable design, waterfront access
Land Use: Compact design, part atop plant, Olympic park

Energy – Emissions Cap and Trade








These systems draw on the power of the marketplace to reduce emissions in a cost-effective and flexible manner. In practice, cap-and-trade systems create a financial incentive for emission reductions by assigning a cost to polluting. First, an environmental regulator establishes a “cap” that limits emissions from a designated group of polluters, such as power plants, to a level lower than their
current emissions. The emissions allowed under the new cap are then divided up into individual permits—usually equal to one ton of pollution—that represent the right to emit that amount.









HOW IT WORKS

Plant A emits 600 tons of CO2 each year, and Plant B emits 400 tons, for a combined annual total of 1,000 tons. An environmental agency then establishes a CO2 emissions cap of 700 tons per year (a 30 percent reduction).

Under a traditional approach, both plants could be ordered to reduce their emissions by 30 percent, which would force Plant A to reduce its annual emissions to 420 tons (a reduction of 180 tons) and Plant B to reduce its emissions to 280 tons (a reduction of 120 tons). The cost for each plant to make emission reductions depends on factors such as plant efficiency and the type of fuel used (e.g., coal, natural gas); in this example, it would cost Plant A an average of $50 per ton and Plant B an average of $25 per ton to meet these reductions, for a total cost of $12,000.

Under a cap-and-trade system, each plant seeks out the lowest-cost way to reduce emissions. Initially, Plant B is able to reduce its emissions at a lower cost than Plant A, so it can sell permits to Plant A. However, the more Plant B reduces its emissions, the more expensive it becomes to make further cuts. Eventually, both plants reach a point where their cost to reduce an additional ton of pollution is equal.

The end result of the cap-and-trade system is that the two plants are able to reach the emission reduction goal set under the cap, but at a lower cost. In our example, we calculate a total cost of $9,000—a savings of 25 percent compared with the traditional approach.

OTHER MODELS

There are cases in which other emission reduction approaches are preferable to cap-and-trade. For example, less flexible regulations are more appropriate when the negative impact of pollution is direct and localized (as with asthma) rather than indirect and global (as with climate change). Cap-and-trade systems are also not very beneficial if the polluters have identical costs for reducing emissions, or if policy makers prefer to be more certain about how much the program will cost rather than how much the environment will benefit.

What’s A Carbon Tax?

A carbon tax is a tax on the carbon content of fuels — effectively a tax on the carbon dioxide emissions from burning fossil fuels. Thus, carbon tax is shorthand for carbon dioxide tax or CO2 tax.

Tax vs. Cap - and -Trade

Note: The New York Times’ Nov. 2 on-line piece, The Real Climate Debate: To Cap or to Tax?, is a superb primer on the carbon-pricing debate. CTC’s Charles Komanoff is quoted for the carbon tax side.

  1. Carbon taxes will lend predictability to energy prices, whereas cap-and-trade systems will aggravate the price volatility that historically has discouraged investments in less carbon-intensive electricity generation, carbon-reducing energy efficiency and carbon-replacing renewable energy.
  2. Carbon taxes can be implemented much sooner than complex cap-and-trade systems. Because of the urgency of the climate crisis, we do not have the luxury of waiting while the myriad details of a cap-and-trade system are resolved through lengthy negotiations.
  3. Carbon taxes are transparent and easily understandable, making them more likely to elicit the necessary public support than an opaque and difficult to understand cap-and-trade system.
  4. Carbon taxes can be implemented with far less opportunity for manipulation by special interests, while a cap-and-trade system’s complexity opens it to exploitation by special interests and perverse incentives that can undermine public confidence and undercut its effectiveness.
  5. Carbon taxes address emissions of carbon from every sector, whereas cap-and-trade systems discussed to date have only targeted the electricity industry, which accounts for less than 40% of emissions.
  6. Carbon tax revenues can be returned to the public through progressive tax-shifting, while the costs of cap-and-trade systems are likely to become a hidden tax as dollars flow to market participants, lawyers and consultants.


BENEFITS

A key advantage of a cap-and-trade system compared with other emission reduction strategies is that it gives companies flexibility in the manner in which they may achieve their emission targets. Another advantage is that it sets a clear limit on emissions. Traditional approaches often focus on emission rates or require the best available technology, but do not always require that specific environmental goals be met. For example, an emissions tax penalizes polluters but does not guarantee the degree to which the environment will benefit, because some companies might find it easier to pay the tax instead of reducing emissions.

Cap-and-trade systems do, however, exert constant pressure on polluters to reduce emissions while allowing flexibility in the process. This encourages companies to meet (or exceed) their emission targets in the most innovative and cost-effective way possible. By promoting innovation, cap-and-trade systems can help slow the pace of global warming while spurring the development of new technologies and industries that will contribute to the long-term growth of the U.S. economy.

www.ucsusa.org

www.carbontax.org

Energy - Replace my Appliances and Lightbulbs



Changing Consumer purchasing patterns
USA

Eleonore de Lusignan

Today in the US, an average home can spend $1,900 on energy costs. By changing your purchasing patterns You can reduce these costs and benefit the environment.

"ENERGY STAR qualified appliances incorporate advanced technologies that use 10–50% less energy and water than standard models."

In 2006 the success of the Energy Star Program led to the reduction of CO2 emissions equivalent to 25 million cars and utility bill savings of $14 billion.

The Energy Star program was with joint efforts from the EPA ( Environmental Protection Agency) and DOE. The Department of Energy has also developed the The U.S. Department of Energy's Appliances and Commercial Equipment Standards Program. This programs sets the energy efficiency standards for manufacturers, creating guide lines, regulations, and testing product procedures.

Now energy star products are readily available. Philips Lighting company is one of the main leaders in fluorescent bulbs. One fluorescent light bulb can last 10 times longer then a standard incandescent light bulb.
Others have followed or also lead the way such as the Federal Government of Australia, who a complete phase out of incandescent light bulb within the next 2 years. Wal-Mart is also making the initiative in their stores by converting all their light bulb, and estimate to save $ 7 million
dollars per year.
For more tips on how you can save energy look at this checklist

Here's the video I was talking about in class about LED paper by GE:




Here's an interactive home that tells you what changes you can do for your home.



Energy-Low Head Hydro


low head hydroelectric power plants
Mary Banas



WHY?
+ Hydropower, given the right site, can cost as little as a tenth of a PV system of comparable output
+ even a modest hydro output over 24 hours a day, rain or shine, will add up to a large cumulative total
+ Hydro systems get by with smaller battery banks because they only need to cover the occasional heavy power surge rather than four days of cloudy weather

Hydro turbines can be used in conjunction with any other renewable energy source, such as PV or wind, to charge a common battery bank. This is especially true in the West, where seasonal creeks with substantial drops only flow in the winter. This is when power needs are at their highest and PV input is at its lowest. Small hydro systems are well worth developing, even if used only a few months out of the year, if those months coincide with your highest power needs.

Use of existing sites:
Many small hydro electric sites were abandoned in the 1950's and 60's when the price of oil and coal was very low, and their environmental impacts unrealized.

HOW IT WORKS
Here are the basic components of a conventional hydropower plant:
• Dam - Most hydropower plants rely on a dam that holds back water, creating a large reservoir. Often, this reservoir is used as a recreational lake.
• Intake - Gates on the dam open and gravity pulls the water through the penstock, a pipeline that leads to the turbine. Water builds up pressure as it flows through this pipe.
• Turbine - The water strikes and turns the large blades of a turbine, which is attached to a generator above it by way of a shaft. The most common type of turbine for hydropower plants is the Francis Turbine, which looks like a big disc with curved blades. A turbine can weigh as much as 172 tons and turn at a rate of 90 revolutions per minute (rpm), according to the Foundation for Water & Energy Education (FWEE).
• Generators - As the turbine blades turn, so do a series of magnets inside the generator. Giant magnets rotate past copper coils, producing alternating current (AC) by moving electrons. (You'll learn more about how the generator works later.)
• Transformer - The transformer inside the powerhouse takes the AC and converts it to higher-voltage current.
• Power lines - Out of every power plant come four wires: the three phases of power being produced simultaneously plus a neutral or ground common to all three.
• Outflow - Used water is carried through pipelines, called tailraces, and re-enters the river downstream

Hydro-electric power plants can generally be divided into two categories:
HIGH HEAD
+ most common
+ utilize a dam to store water at an increased elevation
+ use of a dam to impound water also provides the capability of storing water during rainy periods and releasing it during dry periods
+ consistent and reliable production of electricity, able to meet demand
+ high head plants with storage are very valuable to electric utilities because they can be quickly adjusted to meet the electrical demand on a distribution system.

LOW HEAD
+ utilize heads of only a few meters or less
+ may utilize a low dam or weir to channel water, or no dam and simply use the "run of the river"
+ run of the river generating stations cannot store water, thus their electric output varies with seasonal flows of water in a river
+ a large volume of water must pass through a low head hydro plant's turbines in order to produce a useful amount of power
Hydropower plants harness water's energy and use simple mechanics to convert that energy into electricity. Hydropower plants are actually based on a rather simple concept—water flowing through a dam turns a turbine, which turns a generator.
BENEFITS
Hydro power is better than burning coal, oil or natural gas to produce electricity, as it does not contribute to global warming or acid rain. Similarly, hydro-electric power plants do not result in the risks of radioactive contamination associated with nuclear power plants.
Small scale and low head hydro capacity will probably increase in the future as research on low head turbines, and standardized turbine production, lowers the costs of hydro-electric power at sites with low heads
Low head hydro is more beneficial than high head hydro because:
With high head hydro comes flooding of vast areas of land, much of it previously forested or used for agriculture. The size of reservoirs created can be extremely large. The La Grande project in the James Bay region of Quebec has already submerged over 10,000 square kilometers of land; and if future plans are carried out, the eventual area of flooding in northern Quebec will be larger than the country of Switzerland. Reservoirs can be used for ensuring adequate water supplies, providing irrigation, and recreation; but in several cases they have flooded the homelands of native peoples, whose way of life has then been destroyed. Many rare ecosystems are also threatened by hydro-electric development.
A few recent studies of large reservoirs created behind hydro dams have suggested that decaying vegetation, submerged by flooding, may give off quantities of greenhouse gases equivalent to those from other sources of electricity. If this turns out to be true, hydro-electric facilities such as the James Bay project in Quebec that flood large areas of land might be significant contributors to global warming.
+ high head hydro floods vast area of land which may produce greenhouse gases that contribute to global warming
+ high head hydro disrupts some fragile ecosystems
+ Run of the river (or low head) hydro plants without dams and reservoirs would not be a source of these greenhouse gases.

IMPLEMENTATION
Cajamarca Peru
http://www.microhydropower.net/casestudies/cajamarca.html

Australia
http://www.microhydropower.net/casestudies/small_head_australia.html

Switzerland
http://www.microhydropower.net/casestudies/derendingen.php

SOURCES
howthingswork.com
http://www.solareco.com/articles/article.cfm?id=34