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Building a Path to Ecological Restoration An Institute in India Fights the Desert

Editor’s note: Deserts spread but deserts are not inevitable. Restored ecosystems, managed by humans, can reclaim desertified land through harvesting and storing more rainwater, planting hardy trees that none-the-less yield a crop, and sustainable farming and grazing areas. Such a practice may not stop every desert, but it beats using the land for overgrazing livestock, allowing excess water to run-off each year, and allowing all the trees to die. If tomorrow trees were planted this way everywhere, it might certainly make a positive difference in global climate change. A variety of new farming and forestry technologies and water harvesting practices combine to fight deserts; many of these combinations and recipes for restoration are only now being developed and documented. In India, a country experiencing desertification, an institute in Jodpur, Rajasthan, is pioneering many interesting ways to fight the desert..

Agriculture is not a dependable proposition in this area– after the rainy season, at least 33% of crops definitely fail, stated Dr. Pratap Narain, director of the Central Arid Zone Research Institute (CAZRI), based in Jodhpur, Rajasthan. Animal husbandry, trees and grasses, intercropped with vegetables or fruit trees, is the most viable model for arid, drought-prone regions.

Nand Kishore Jaisalmeria, a local farmer who has won national awards for his progressive approach to agriculture, said current drought conditions have cost him a 30-40% loss.

The Great Indian Desert Stretches over much of Northwest Central India (Scale: 100 miles = 41 pixels)

Arid regions of Western Rajasthan, Gujarat, and Southern parts of Haryana receive low precipitation (under 40 CMS. normally) with high evapotranspiration due to high solar radiation and wind speed. The region faces frequent droughts. Overgrazing due to the high animal population, wind and water erosion, mining and other industries are serious land degradation processes, according to Dr. Narain.

“Certain oceanographic features may be the cause of the current drought and shift in climate,” he said. “We don’t have good oceanographic stations yet; we can only offer medium-range weather forecasting, which means about 15 days in advance. We can’t say when the monsoon, or any other rain will come.”

In the last 15-20 years, the Rajasthani desert has seen many changes, including a manifold increase of both the human and animal population. Animal husbandry has become popular due to the difficult farming conditions. At present, there are ten times more animals per person in Rajasthan than the national average, and overgrazing is also a factor affecting climatic and drought conditions.

Central Arid Zone Research Institute

Since its establishment in 1959, CAZRI, funded primarily by the Indian Council of Agricultural Research, has been working under the mandate of undertaking basic and applied researches in order to contribute to the development of sustainable farming systems in the arid ecosystems.

In 2001, CAZRI established five multi-purpose tanks of 50,000 litre capacity to help meet drought needs, for which the cost was shared with farmers. Three 20-meter deep infiltration wells were established to enhance groundwater recharge, and subsurface barriers across the ephemeral stream increased well yield from 28% to 53%. Vegetative barriers, perhaps the most non-invasive way to conserve water, prevent runoff, and increased the yield of crops like pearl millet and mung bean in some areas from 30 to 50%.

In August of 2002 CAZRI held a drought management conference to discuss what they should reccomend that the goverment do in terms of drought-proofing and prevention. The scientists concluded that crops requiring less water should be cultivated, and that rooftop rainwater harvesting systems should be mandatory in the construction of new buildings. This water can be used for crops.

Newly Planted Budding Ber Trees

In the short term, it was agreed at CAZRI’s 2002 Conference that relief work must be done, like supplying grain and fodder for animals, and cleaning existing wells. For the long term, however, issues like how land-use policies might be adjusted and how people can be encouraged to grow more grasses and legumes came up.

“Right now survey teams are collecting data from farmers,” said Dr. Narain. “We want to fuse technology with the indigenous wisdom of farmers, and learn how they are coping with the drought. After surveying, we will make a publication, and then submit it to the goverment.”

Dr. Narain emphasized, however, that CAZRI is primarily an agricultural research institute. Construction is the responsibility of the state government. Technology is developed at CAZRI, and then the state mechanism for distribution takes over. As he puts it “Our work is in planning, not execution.”

Improved varieties of crops like low-rainfall grasses, for example, particularly Dhaman (Cenchurs cilaiaris) & Sewan (Lasiurus sindicus) have been developed in seed and pellet form which can be sown by helicopter, according to Dr. Nairain.

The scientists of CAZRI have successfully developed and improved dozens of traditional and non-traditional crops/fruits, such as Ber trees (like plums) that produce much larger fruits than before (lemon-size) and can thrive with minimal rainfall. These trees have become a profitable option for farmers. One example from a case study of horticulture showed that in situation of budding in 35 plants of Ber and Guar (Gola, Seb & Mundia variety developed in CAZRI), using only one hectare of land, yielded 10,000 Kg. of Ber and 250 Kg. of Guar, which translates into double or even triple profit.

The Drought-Resistant Kejari Tree

Acacia Senegal, a tree imported from Africa 25 years ago, has adapted well to the Indian desert. CAZRI has developed ethophil injection, an etheline compound which increases the gum production of the tree by 25-35%. This gum is used for eating and in various medicines.

Technology is transferred via field days, farmers’ fairs, exhibitions, training, and on-farm trials. It adopted the new technology developed by CAZRI in 1976 by budding an improved variety of Ber,” said Mr. Jaisalmeria, a local farmer. “It started giving good results in 2-3 years and gave a new crop idea to contemporary farmers.”

He said the CAZRI ber trees had helped prevent soil erosion, and proved to be one of his most drought-resistant crops, along with indigenous trees like Neem, Khajeri and Rohira. “Now 1,000,000 hectares of land (even sand dunes) is being cultivated which was not of any use before,” he said.

One major area of CAZRI’s achievement is the rehabilitation of wastelands created by the large-scale mining of minerals like limestone and gypsum, which are found in abundance in arid zones.

Technologies integrating suitable plant species, soil amendments and water harvesting have been developed, and many such wastelands have been successfully revitalized. Furthermore, scientists have identified several species of trees that can be planted on land contaminated by chemicals used in printing and dyeing clothes.

Sand Dunes Cover 58% of Rajasthan

About 58% of the area of arid Rajasthan is occupied by highly mobile sand dunes, a serious danger to farms, canals, highways, and generally everyone living in the arid regions, and are a contributing factor to increased desertification. The institute has established shelterbelts consisting of three rows of trees: a central row of tall trees like Albizzia lebbek, with one row of branching trees like Acacia tortolis, Cassia siamea or Prosopis juliflora on either side. These shelterbelts have proved to reduce wind velocity by 20-46%, and soil loss by 76%. To date over 16,000 ha of land has been stabilized using this method.

Also contributing to combatting desertification is CAZRI’s long-going project of mapping the desert, and identifying and understanding the processes leading to desertification. Using sattelite imagery, the extent of soil movement has been quantified, and underground courses of rivers like Saraswati have been located.

These discoveries were confirmed through geophysical depth sounding, and later successfully used for groundwater exploration.

In the area of livestock management, which is an important source of sustenance for farmers in drought years, an animal feed block compression machine was developed in 2002 which compresses the feed 3-3.5 times, producing blocks of 2.5 kg weight. This reduces the costly burden of transporting large quantities of bulky animal feed. The machines now are being manufactured by private companies.

CAZRI scientists have also recently identified a new breed of sheep, Parbatsar, which has a higher growth rate, milk yield and duration of lactation. A technique of ensiling surplus fodder, using over-fermented milk, urea and molasses, has been developed.

Hindi Newspaper Dainik Bhaskar

Another recent discovery, heralded by Dainik Bhaskar, a Hindi national newspaper, is the development of fresh water fish that can survive in brackish (salty) water. Dr. Narain explained that Panaeus monodon shrimp and Seabass fish fry were reared with 92% survival and an average weight of 38 GMs and 12 GMs respectively in 140-150 days. Grey mullet fish could be grown to 1.4 GMs in 39 days in winter at 12-18 degree centigrade in waters up to 45 parts per thousand salinity. On March 16, a fair was held for over 300 participants, sharing this technology and seeds with willing farmers.

“We have contacted the Fishery Department and banks to help with financing,” said Dr. Narain. “Farmers will need to make fish ponds. CAZRI can give low-profit or free prawn seeds.”

The recent discovery of the Dhingri Mushroom, which can be grown easily in arid regions, also proves to be a profitable new crop. Mushrooms were previously transported from remote areas, and are therefore expensive here.

Other findings include finding of anti-HIV constituents viz. Betulinic acid (BA), oleanolic acid (OA) and ursolic acid (UA) which were extracted and isolated by column chromatography, using standard protocol from Tecomella Undulata (Rohira). However, this is only a preliminary finding, caution researchers, which is currently being clinically tested by the Central Drug Research Institute, Lukhnow.

Although CAZRI is doing a great favour to the farmers in this region, still the regular drought and the poverty make the difference. And the rain is the thing which brings smile on the faces.

Brook and Gaurav Bhagat are writers and independent filmmakers based in Jodhpur, Rajasthan, India.

Planting New Mangrove Forests

Many of us don’t realize how lucky we are to have access to all the water we want. Showering or bathing every day, dishwashing with the faucet on full blast, or owning a swimming pool is unthinkable in many countries. Water is not divided equally around the world. While Americans happily feed koi in backyard ponds, others in the Middle East or Africa, for example, have to wait for a truck to deliver their monthly supply of water. Walking five miles to the nearest community well and back is not an uncommon practice in these regions. “I’m not convinced that there are water shortages as much as there are problems with water distribution” says Linda Platt, an editor at the Political Economy Research Center (PERC), who like many of us, believes that many regions are at a disadvantage when it comes to water availability for farming, drinking, or simple hygiene.

With oceans covering more than 70% of the earth’s surface, it is ironic that usable water is not an abundant commodity. Less than 1% of water on the planet comes in the exploitable form of lakes, streams and groundwater. The potential of saltwater has been contemplated for years, but only recently have there been advances in operations that utilize this abundant resource.

Eritrea has deserts and coastline perfect for salt water agriculture

Carl Hodges, an atmospheric physicist at the University of Arizona, came up with an ingenious plan to overcome the freshwater shortages that many farmers face in arid countries. This plan, financed by University of Phoenix founder John Sperling, came in the form of Seawater Farms. “This project is still in the experimental stages,” says Linda Platt, editor of PERC, “but Seawater farms seems to have found a way to produce environmental goods without overexploitation of the environment.” Seawater Farms, established in the small African country of Eritrea, uses saltwater to sustain an array of shrimp, fish and plants. Amazingly, it doesn’t stop there: The remaining water even irrigates and sustains wetlands and mangrove forests that naturally occur in the region. They have also planted numerous trees in the hopes of establishing habitats for the fauna in the region.

“The life the mangroves support is tremendous,” says Jugal Tiwari, staff ecologist of the Seawater Farms and the Seawater Forests Initiative. “I have seen at least 100 species of insects, including 4 species of butterflies and 12 species of moths. Doves, Warblers and Prinias nest in the mangroves a well, and there are at least 14 different kind of crabs, including fiddler crabs. This year over 1 million seedlings were raised by the foresters of Seawater Forests Initiative. Each of the 15,000 mangrove plants we have planted in the 10 hectares of area is supporting a lot of life.”

“The number of bird species that have come to inhabit our farm has grown from an estimated dozen to well over 200,” says Howard Weiss, also of the Seawater Forests Initiative.

Mangrove Forest in Eritrea

“The mangroves are equally important in sequestering the atmospheric carbon and making environment pollution free,” says Jugal Tiwari, “We are basically a group of people who think global and take the challenge of converting the so called coastal wastelands (4.2 million hectares of such coastal wastelands in Eritrea) into green land using just the ocean’s salt water. As you know fresh water in such areas is a limiting factor and so deficient that people can’t find enough water to survive.”

The farming system is quite effective: Untreated salt water is brought inland through a 3-mile long canal to salicornia fields which, unlike most crops, are able to grow efficiently in this salty environment. The principal field crop, Salicornia, provides a gourmet vegetable from its young shoots. The mature plant provides seed that produce a fine, edible oil and a high protein meal. There is also a large amount of biomass, which can be used for animal fodder, particleboard, and firebricks.

Not all seawater flows directly to these plants; some diverges and flows into shrimp tanks and later 3 salt lakes containing different species of fish. The shrimp species Penaeus vannamei is the gem of Seawater Farms Eritrea aquaculture. This species tolerates variations in salinity, temperature, pH and oxygen levels that allow it to be as suited to farming as it is profitable. Another species of shrimp, Penaeus indicus, arrived in seawater farms unexpectedly through the seawater canals connecting the farms to the red sea. This added little bonus, with its popular flavor, has been a big boost to Seawater Farms’ business.

The Tilapia Fish is Farmed Worldwide

Fish were also incorporated into this intricate project. Originally, the plan was to just farm the tilapia fish. This useful species, naturally occurring in the Middle East and Africa is now farmed worldwide. At seawater farms, these fish are not just a food product; Their skin is similar to leather when dried and is used to make a variety of products whereas the leftover heads are recycled for shrimp feed. Another species of fish, the milk fish or chanos chanos, unexpectedly rode in on the seawater stream and has now established itself in the shallow waters of the mangrove park in addition to the tilapia. This is yet another bonus for the Farm.

The waste from the shrimp and fish is carried by water to fertilize the salicornia fields. This versatile agricultural system has worked extremely well, while the reestablished wetland parks, created by the overflowing seawater, are very much appreciated by wildlife residing in the area. No seawater is wasted either: It is absorbed by the soil and returns to its starting point-the red sea.

Unfortunately, Seawater agriculture can only “be confined to coastal deserts because if seawater were brought inland, it would ruin the land unaccustomed to the high salinity. Saltwater agriculture further inland would be a disaster” says Emanuel Epstein, a professor and highly respected researcher of plant biology at the University of California, Davis.

Salt Water Agriculture A Field of Salicornia

Epstein has also had a fair amount of success with saltwater agriculture during the 1970s and 80s. “Why not start out with plants that are already economically useful such as wheat and rice which feed 2/3 of mankind instead of imposing economic usefulness on other plants such as salicornia,” says Epstein. “I was fairly successful in harvesting barley, wheat and tomatoes selected and bred for salt tolerance.” The scheme discussed [regarding salicornia] starts with naturally occurring wild plants. “An alternative approach,” continues Epstein, “is to start with established crop species, such as wheat or rice, which are salt sensitive, and by means of genetic and molecular biological methods engineer salt tolerance into them. The feasibility of this approach was demonstrated over 30 years ago at Bodega Marine Laboratory, with wheat, barley, and tomatoes and the likelihood of success has greatly improved since then as a result of the spectacular advances in molecular biology.”

Seawater Farms currently focuses on salicornia fields but genetic research funded by John Sperling is being done in the hopes of using other more ‘profitable’ species in this type of agriculture.

Seawater Farms is both ecologically acceptable and profitable. The first shrimp harvest, for example, was worth nearly 12 million dollars. Seawater Farms has also revolutionized coastal agriculture as we know it. It has given hope to farmers who are limited by the lack of freshwater available while the Seawater Forests Initiative has breathed life into forests that reside in an otherwise dry, desert environment.

EMAIL TO THE EDITOR

—–Original Message—–

From: Jane Poynter [mailto:anon@anon.com]

Sent: Wednesday, December 03, 2003 4:57 PM

To: ed@ecoworld.com

Subject: Seawater Farms and Forests

In your great article about salt tolerant crops, featuring Seawater
Farms Eritrea and Seawater Forests Initiative, I would like to point out
a discrepancy in the quote by Epstein regarding genetically engineering
standard crops, such as wheat and tomatoes, for salt tolerance. He is
referring to something quite different from what salicornia can do. Salt
tolerance in his context means plants that can grow in water that would
be too salty to grow normal agricultural crops, but is far less saline
than pure seawater by many parts per thousand. Salicornia bigolovii,
which has been bred to produce a high quality oil seed, grows on pure,
untreated seawater. Something quite different altogether.

Jane

Capitalism leads to wealth, wealth leads to investment, investment spawns innovation, and through glorious creative destruction, today’s innovations surpass and replace yesterday’s, creating more wealth. Through capitalist initiative, civilization has advanced beyond the wildest imaginings of our forbears. Today we cure diseases that were incurable. We cultivate miracle crops to feed the world. There is no problem in that cannot eventually be solved if we just give capitalist entrepreneurs free rein.

Yet in spite of compelling evidence, the capitalist system remains challenged. Globalization, privatization, the growth of intellectual property law, industrialization, mechanization, and free trade have all spawned resistance. Voices raised include socialists, environmentalists, indigenous peoples, humanitarians and even other capitalists.

The following Capitalist Myths, each embraced by far too many capitalists, dangerous when adopted blindly, can be amended or eliminated through more serious debate. Capitalism is a powerful force for positive change, but cannot realize its full potential unless it acknowledges and confronts its myths, and assimilates positive ideas from belief systems besides its own.

Myth #1
Global Free Trade is Always Best

What is Fair and Free Trade? Read “Global Exchange”

Not always. While a world of unfettered free trade can create faster overall economic growth, that same growth can cause some societies and countries to become worse off. Suddenly introduced global free trade can turn an entire country’s economy and fledgling local industries upside-down. Foreign investment often focuses on over-development of single commodities that can go bust. Increased foreign investment and global trade usually ride into a country alongside debt. Going into countries using international legal weaponry to enforce free flow of capital and foreign ownership of local assets isn’t always best. Alongside free trade there is fair trade, an equally elusive and worthy goal.

Myth #2
Cheaper is Always Better

Price competition is a pillar of capitalism, but many measures of value do not immediately or easily translate into quantities of money. How can the happiness of a people, or the health of an ecosystem appear on the financial statements of a multinational corporation? Hire lower-paid employees and lay them off and move to another country as soon as it’s cheaper there, then move again. Mechanize the workplace and make workers commodities. Log forests on cheap land, pay massive short-term profits into dividends and close the company. Strip-mine oceans with driftnets 50 miles long and kill off the final scattered fish with high-tech sonar detection systems. Capitalist competition means more, cheaper, faster; cheaper goods, cheaper shelter, and cheaper protein, but it’s not always better.

Myth #3
Capitalism has European Roots

Only some capitalists are European. The functions of capitalism; property ownership, monetary exchange, trade, competition, value creation and entrepreneurship, easily predate Europe and exist and originate from most everywhere. Private individual wealth and multinational corporations come from diverse cultures. That the Europeans have been successful capitalists doesn’t mean they invented capitalism, and it doesn’t automatically consign capitalism to European values and prerogatives. Critics of capitalism point their fingers at the west more than the west deserves. Capitalism is part of human nature.

Myth #4
Intellectual Property is Sacred

Where does public domain begin? Read “Monocultures of the Mind”

Absolutely not! Patents for inventions that incorporate life forms, mimic natural processes or copy native remedies and recipes are walking on legal thin ice. “Business method” patents are complete baloney and should be repealed. Maybe copyrights last too long, and royalties cost too much. The public domain is under attack and it’s shrinking. Farmers who save and reuse seed from their own crops, inadvertently or effortlessly cross-pollinated with windblown genetic material that somebody patented should not be prosecuted. Open source legal precedents are already set in the software industry. Stakes are high. Intellectual property law run rampant becomes an expensive and devastating tool for oligarchic and other vested interests to outlaw competition. How capitalist is that? It’s time to reverse this trend. There is an intangible commons, too.

Myth #5
Industrialization is the Only Alternative

From a global perspective industrialization is inevitable, but that doesn’t mean developing countries should develop now or else. Countries that would have enjoyed relative stability if they’d never industrialized can be sorely disrupted by sudden financial flight. Single commodity economies with debt service blow in the wind. When a country commits to industrialize they place high bets in limited areas and they run this risk. Moreover, because global productivity constantly improves, especially in the high-tech era we live in, the longer a country waits to develop, the less they will have to pay for their new industries. Countries should not be rushed into industrialization because it’s supposedly in their interests.

Myth #6
Property is Sacred.

Who Owns the Oceans? Read “David Brower’s Legacy”

Never. Too much of the property we might consider sacred is also shared between us. If the air is unhealthy for people to breath, or the water too poisonous for fishermen to fish, some property owner’s prerogative, and resultant pollution, is definitely not sacred. Productive assets necessary to society, especially when controlled by monopolies, cartels, or foreign financial interests, must be regulated to ensure sustainable practices and a safety net for the poor. Property rights defenders are correct to call regulations “takings,” but that per se is not at issue. Governments must regulate trade to enforce “free trade,” they must regulate commerce to encourage and enable competition, and they should help protect the weak; all of which can translate into “takings” in some form. The only question is when, and how much.

Myth #7
Democracy-Capitalism is the End-Point of Civilization

Really now? Then go explain how corporate welfare fits into this rosy picture, for starters. Democracy-Capitalism has today’s media and mainstream academic endorsements, but utopia nonetheless eludes modern civilization. To strive for democracy-capitalism, ideally, is an ongoing fight against tyranny and oligarchy from any group, creed or political ideology. Capitalists can be tyrants. Democracies can be belligerent. The form of capitalism and the ethics of democratic societies are diverse and subtle and need constant reexamination. Congratulating democracy-capitalism as the end-point of civilization shouldn’t discourage or take the place of relentless investigation and reporting, healthy dissent, and meaningful public debate.

Myth #8
Privatize Public Works

Can Everything be Privatized? Read “The Giants of Water”

It depends. Many if not all public works provide necessities such as water and energy that cannot be found anywhere else. These necessities should be offered free to those who cannot afford to pay. Privately operated public works, owned by foreign interests, could in unregulated free-trade environments be managed as cash-cows, exporting profits into a multi-national conglomerate instead of back into the local economy. There is no monopoly on corruption, which can affect private corporations inside or outside a country just as severely as it might affect public administrations anywhere. Public works can succeed as mostly public or mostly private operations.

Myth #9
Maximize Quarterly Profits

This is a canard disguised as a rationalization turned into an obligation compelling a property owner to cut down all the trees in their forest, or pump out all the water from their aquifer, selling to the highest bidder as quickly as possible. Every industry has its culprits, compulsive competitors who cut every corner, cook the books, betting the farms, heedless of the ultimate payback. In the name of short-term gain people can become puppets and chattel, worthy enterprises ignored and abandoned, and the earth stripped. In the long run human rights always prevail, ecosystems are stewarded, and business is sustainable. It is much easier for a long-term capitalist to profit without creating victims and collateral damage. If all that really mattered were to maximize quarterly profits the world would already be a wasteland.

Myth #10
Greed is Good

Pure crap. Greed is a sin, not a virtue, but it can be confused and conflated with one of capitalism’s moral appeals; that capitalism offers, hopefully, a competitive and pluralistic game where no one sinful, awful faction can ever dominate. In this pragmatic model greed is not good it is contained. But capitalism, ideally, also depends on a totally voluntary moral framework and consensus in societies that greed is not good. Only then does capitalism better avoid caricature and condemnation. Only then do capitalist visions have more universal appeal and overall joy.

Capitalism at its best is the engine that will bring peace and prosperity to humanity, eliminate poverty and disease, and protect the earth. But building enthusiasm for capitalism throughout the world requires patience and compromise, possibly slower but more sustainable economic and corporate growth, and more diverse patterns of ownership.

To proliferate faster, more capitalists might prefer not myths that only emphasize the economic game, but instead visions of a better world. Visions where most everyone, especially the avid capitalists, believe that humanity and ecology weigh in equally alongside winning.

Ed Ring is Editor and CEO of EcoWorld Inc., publisher of www.EcoWorld.com.

Five Megawatt Offshore Wind Turbines Are Now Being Installed

Options for exploiting the energy available from the world’s oceans include offshore wind, wave and tidal stream energy. Offshore wind is by far the closest to commercial exploitation, but the range of possibilities is surprisingly broad.

Offshore wind is set for rapid development and could become fully commercial in 15-20 years. However, both wave and tidal stream energy face one of the so-called ‘valleys of death’ in the development of successful innovation – that between the prototype and wide utilisation. Some, perhaps many, of the current companies and designs will fall by the wayside. Nevertheless, wave and tidal hold considerable promise for the longer term.

Extracting clean and economically viable energy from the world’s oceans has fascinated researchers and engineers for centuries. The first patent on a wave energy device was taken out in 1799, and more than 300 such devices have been patented since. Commercial application has been limited to a small number of devices that use wave energy to power navigation buoys. However, concerns over climate change may fuel progress. All of the marine renewables offer energy with low environmental impact and near-zero emissions.

European Union

While estimates of resources available depend upon assumptions about technology and the availability of suitable sites, all options are able, in principle, to provide large amounts of electricity. Global resources have not been mapped in detail, but studies of EU and UK resources provide an indication of the scale of the potential. Offshore wind could provide 900 terawatt-hours (TWh) per year in Western Europe, and wave 50-700 TWh/year in UK waters alone. Tidal resources appear more modest: 48 TWh has been identified in EU waters, but at present only limited sites have been considered. (UK electricity consumption is around 380 TWh/year.)

Here is an assessment of the economic prospects for deriving energy from ocean wind, waves, and tides.:

OCEAN WIND ENERGY

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Maritime Denmark is a World Leader in Low-Cost, Large-Scale Wind Energy

Offshore wind has benefited from progress made onshore over the last 20 years. Costs have fallen dramatically – in good locations it is almost competitive with conventional energy sources. Turbines have grown from less than 100 kilowatts (kW) to 1 megawatt (MW) or more. Offshore wind farms under development feature turbines of 2 MW, and 3-5 MW turbines are widely predicted to become available soon. Large turbines are essential if offshore wind is to deliver energy at acceptable cost, and this is one reason why the stage is set for developments offshore.

Offshore wind involves additional costs in installation, cabling and maintenance, with existing plants generating at 4.5-7 US cents per kWh – twice the cost of developments on land. However, wind regimes are typically more stable offshore and the absence of noise constraints means turbines can spin faster, which raises efficiency and reduces costs. Current developments in turbine design, experience in installation and operation, and economies of scale as the industry expands, suggest costs will fall. Costs halved between Denmark’s Vindby development in 1991 and its recent Horns Rev project. A recent study for the UK government concluded that offshore wind costs are likely to fall to 3-5 US cents per kWh by 2020. Although less than 100 MW of offshore wind is currently installed worldwide, this is expected to grow to 3 gigawatts (GW) by 2005 because individual offshore wind farms can be large. Several developments of 100-500 MW are being built.

OCEAN WAVE ENERGY

Power generation using wave energy is at a much earlier stage of
development. Wave energy offers more predictable outputs than wind, but in early 2003
there was only around one megawatt of generating capacity installed worldwide, all of it essentially with demonstration prototypes. Proposed projects are likely to take this to about 6 MW over the next few years. The wave industry is characterised by a wide variety of novel devices
and a large number of small firms. Devices can be classified by generic technology type, though there is some overlap:

Types of Wave Energy Devices:

Inexhaustible Electricity from Wave Energy Can Already Cost Under $.06 per Kilowatt Hour

* Pneumatic devices, such as the oscillating water column (OWC), use wave motion to compress and decompress air, and drive a turbine.

* Float-based devices utilise a buoyant float moving with the waves, reacting against a sea bed anchor in order to harness energy.

* Spillover devices utilise wave height to replenish a reservoir of seawater, which runs a turbine.

* Raft-type devices use the relative motion of adjacent rafts or pontoons to harness wave energy.

* Moving-body devices articulate in the water, inducing motion, which may be used to drive a hydraulic motor.

Commercial-scale wave energy is yet to become a reality and as such empirical evidence on costs is limited. Of those devices that have been deployed (for the most part near-shore and shoreline OWC devices), costs are in the region of 6-8 US cents per kWh. Three designs – the Limpet, Osprey and Pelamis – have secured support from the Irish and Scottish renewables schemes – though supplementary investment has also been required (for example, EU grants). The other devices are still at the research stage, though some are much closer to commercial deployment than others. (Float based devices are already in use for niche applications such as navigation buoys.) The Osprey is designed to provide a mounting platform for wind turbines and hence offers the prospect of the first hybrid wind-wave device. Hybrids have the potential to improve the utilisation of sub-sea power connections and to raise the ratio of output to construction cost.

OCEAN TIDE ENERGY

A Seabed-Mounted Tidal Energy System is now being tested off the U.K.’s Shetland Islands

Tidal stream devices extract energy from the diurnal flow of tidal currents (caused by the gravitational pull of the moon). Unlike wind and wave power, tidal streams offer entirely predictable output. However, as the lunar cycle is of around 25 hours’ duration, the timing of peak outputs differs by around an hour each day and tidal energy cannot be guaranteed at times of peak demand.

Typically, tidal turbines, similar in appearance to wind turbines, are mounted on the seabed. They are designed to exploit the higher energy density, but lower velocity, of tidal flows compared to wind. Tidal stream differs from established technology for exploiting tidal energy (eg estuarine tidal barrages, such as the 240 MW barrage operating in France) in that tidal flows are not captured and controlled by means of a large dam-like structure. Rather, tidal turbines operate in the free flow of the tides, meaning that large construction costs and disruption of estuarine ecosystems associated with barrages may be avoided. However, as tidal streams are a diffuse form of energy and the purpose of the barrage is to concentrate tidal flow, this also means that large numbers of turbines, spread over relatively large areas of seabed, are required if significant amounts of energy are to be extracted.

Until recently, the diffuse nature of the resource, combined with the relatively high costs of engineering and installing turbines able to withstand the rigours of the sea, confined tidal stream to university laboratories. However, several large grid-connected demonstration projects are expected to enter the water in the near future. Tidal stream is thus a few years behind wave energy.

Seabed-Mounted Tidal Energy Lowering A Tidal Propeller Marine Current Turbines

Marine Current Turbines is about to field test a submerged 300 kW tidal turbine off Devon in the United Kingdom, and a seabed-mounted system called Stingray is being tested off the Shetlands. Both have EU and UK government funding. A novel device called the Rochester Venturi, which uses tidal flow to draw a working fluid through turbines mounted onshore and hence has no moving parts under water, is also expected to enter large-scale demonstration soon. The manufacturers of all these devices expect to deliver
energy at a cost of 10-14 US cents per kWh, falling to below 6 US cents as
experience grows and technologies mature

About the Author:
Gordon Feller is the CEO of Urban Age Institute (www.UrbanAge.org). During the past twenty years he has authored more than 500 magazine articles, journal articles or newspaper articles on the profound changes underway in politics, economics, and ecology – with a special emphasis on sustainable development. Gordon is the editor of Urban Age Magazine, a unique quarterly which serves as a global resource and which was founded in 1990. He can be reached at GordonFeller@UrbanAge.org and he is available for speaking to your organization about the issues raised in this and his other numerous articles published in EcoWorld.