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Scurvy is a disease now known to be caused by a deficiency of vitamin C, but in Lind’s day, the concept of vitamins was unknown. Vitamin C is necessary for the maintenance of healthy connective tissue. In 1740 the catastrophic result of Anson’s circumnavigation attracted much attention in Europe; out of 1900 men, 1400 had died, most of them allegedly from having contracted scurvy. According to Lind, scurvy caused more deaths in the British fleets than French and Spanish arms.

Since antiquity in various parts of the world, and since the 1600s in England, it had been known that citrus fruit had an antiscorbutic effect, when John Woodall (1570–1643), an English military surgeon of the British East India Company recommended them but their use wasn’t widespread. Although Lind was not the first to suggest citrus fruit as a cure for scurvy, he was the first to study their effect by a systematic experiment in 1747. It ranks as one of the first clinical experiments in the history of medicine.

Lind thought that scurvy was due to putrefaction of the body which could be helped by acids; that is why he chose to include a dietary supplement of acidic quality in his experiment. This began after two months at sea when the ship was afflicted with scurvy. He divided twelve scorbutic sailors into six groups. They all received the same diet but, in addition, group one was given a quart of cider daily, group two twenty-five drops of elixir of vitriol (sulfuric acid), group three six spoonfuls of vinegar, group four half a pint of seawater, group five received two oranges and one lemon and the last group a spicy paste plus a drink of barley water. The treatment of group five stopped after six days when they ran out of fruit, but by that time one sailor was fit for duty and the other had almost recovered. Apart from that, only group one also showed some effect of its treatment.

Shortly after this experiment Lind retired from the Navy and at first practised privately as a physician. In 1753 he published ”A treatise of the scurvy”, which was virtually ignored. In 1758 he was appointed chief physician of the Royal Naval Hospital Haslar at Gosport. When James Cook went on his first voyage he carried wort (0.1& mg vitamin C per 100 g), sauerkraut (10–15& mg per 100 g) and a syrup, or ‘rob’, of oranges and lemons (the juice contains 40–60& mg of vitamin C per 100 g) as antiscorbutics, but only the results of the trials on wort were published. In 1762 Lind’s ”Essay on the most effectual means of preserving the health of seamen” appeared. In it he recommended growing salad, i.e. watercress (662& mg vitamin C per 100 g) on wet blankets. This was actually put in practice, and in the winter of 1775 the British Army in North America was supplied with mustard and cress seeds. However Lind, like most of the medical profession believed that scurvy was essentially a result of ill digested and putrefying food within the body, bad water, excessive work and living in an damp atmosphere which prevented healthful perspiration. Thus, while he recognised the benefits of citrus fruit (although he weaken his case by switching to a boiled concentrated or ‘rob’, the production of which unfortunately destroyed the vitamin C), he never advocated citrus juice as a single solution. He believed that scurvy had multiple causes which therefore required multiple remedies.

The medical establishment ashore continued to be wedded to the idea that scurvy was a disease of putrefaction, curable by the administration of elixir of vitriol, infusions of wort and other remedies designed to ‘ginger up’ the system. It could not account for the benefits of citrus fruits and dismissed the evidence in their favour as unproven and anecdotal. In the navy however, experience had convinced many officers and surgeons that citrus juices provided the answer to scurvy even if the reason was unknown. On the insistence of senior officers, led by Rear Admiral Alan Gardner, in 1794 lemon juice was issued on board the ”Suffolk” on a twenty-three week, non-stop voyage to India. The daily ration of two-thirds of an ounce mixed in grog contained just about the minimum daily intake of 10& mg vitamin C. There was no serious outbreak of scurvy. This astonishing event resulted in a widespread demand within the navy for lemon juice, backed by the Sick and Hurt Board whose numbers had recently been augmented by two practical naval surgeons who were well aware of Lind’s experiment with citrus. The following year the Admiralty accepted its recommendation that lemon juice should be issued routinely to the whole fleet. Another Scot, Archibald Menzies, picked up citrus plants and dropped them off at Kealakekua Bay in Hawaii on the Vancouver Expedition, to help the Navy re-supply in the Pacific.

This was not the immediate end of scurvy in the Navy, as lemon juice was at first in such short supply that it could only be used in home waters as a cure under the direction of the surgeons rather than issued routinely as a preventative. Only after 1800 did the supply increase sufficiently so that, on the insistence of Admiral Lord St Vincent, it began to be issued generally.

Prevention of Typhus

Finding that typhus disappeared from the top floor of his hospital, where patients were bathed and given clean clothes and bedding, while it raged through the floors below where such hygiene measures were not in place, Lind recommended that sailors be stripped, shaved, scrubbed, and issued with clean clothes and bedding regularly. As a result, British seamen did not suffer from typhus, giving the British navy a significant competitive advantage over the French.

Fresh water from the sea

In the 18th century sailors took along water, cordial and milk in casks. According to the ”Regulations and Instructions relating to His Majesty’s Service at Sea”, which had been published for the first time in 1733 by the Admiralty, sailors were entitled to a gallon of weak beer daily (5/6 of the usual British gallon, equivalent to the modern American gallon or slightly more than three and a half litres). As the beer had been boiled in the brewing process it was reasonably free from bacteria and lasted for months unlike water kept in a cask for the same time. In the Mediterranean, wine was also issued, often fortified with brandy.

A frigate with 240 men, equipped with stores for four months, carried more than a hundred tons of drinkable liquid. Water quality depended on the original source of the water, the condition of the casks and for how long it had been kept. During normal times sailors weren’t allowed to take any water away. When water got scarce, it was rationed and rain water was collected with spread sails. Fresh water was also collected when an opportunity presented itself ”en voyage”, but watering places were often marshy, and in the tropics infested with malaria.

In 1759, Lind discovered that the steam of heated salt water was fresh. He also proposed to use solar energy for the distillation of water. But only when a new type of cooking stove was introduced in 1810 did the possibility arise of producing fresh water by distillation on a useful scale.

Adapted from the Wikipedia article James Lind, under the G. N. U. Free Documentation License. Please also see http://en.wikipedia.org/wiki

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Solar power

Initial designs for a GREEN cell proposed that each GREEN Cell opens two doors length-wise, thus covering neighboring containers as well. The inside of the doors, and much of the exposed surface of the container are mounted with solar panels. Thus, a typical container ship could cover its entire surface with solar energy panels. One GREEN Cell produces as much as 1000& ft2 of solar panel surface area. This equates to roughly 12& kW. 100 such containers could thus conceivably produce 1.2 MW. Alternate calculations show that such a system would retrieve 500 Watts per m2. Multiplied by the approximately 20,000 m2 of surface area on a large container ship like Emma Maersk would give 10 MW of solar energy.

Wind power

An extendable vertical-axis windmill emerges from one side of the container. A vertical-axis windmill is preferred as it introduces less resistance to the forward motion of the ship and disturbs ship stability less than horizontal-axis windmills.

Stored chemical power

The battery of the GREEN cell takes up the remainder of the space in the container. Designers describe the potential battery as either an optimised lithium-ion battery, or a sodium-sulfur one.

Adapted from the Wikipedia article GREEN Cell Shipping, under the G. N. U. Free Documentation License. Please also see http://en.wikipedia.org/wiki

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The event is primarily sponsored by the US Department of Energy and includes a decathlon of 10 individual contests for the students and their homes. It takes place biannually in October on the National Mall in Washington, D.C. The teams’ houses and the sponsors’ educational exhibits form a solar ‘village.’ The public, media, industry representatives and invited dignitaries tour the homes and exhibits and learn about the powerful combination of solar energy, energy efficiency and the best in home design.

Adapted from the Wikipedia article Alberta Solar Decathlon Project, under the G. N. U. Free Documentation License. Please also see http://en.wikipedia.org/wiki

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Wind power is derived from uneven heating of the Earth’s surface from the Sun and the warm core. Most modern wind power is generated in the form of electricity by converting the rotation of turbine blades into electrical current by means of an electrical generator. In windmills (a much older technology) wind energy is used to turn mechanical machinery to do physical work, like crushing grain or pumping water.

Hydropower is energy derived from the movement of water in rivers and oceans (or other energy differentials), can likewise be used to generate electricity using turbines, or can be used mechanically to do useful work. It is a very common resource.

Geothermal power directly harnesses the natural flow of heat from the ground. The available energy from natural decay of radioactive elements in the Earth’s crust and mantle is approximately equal to that of incoming solar energy.

Alcohol derived from corn, sugar cane, switchgrass, etc. is also a renewable source of energy. Similarly, oils from plants and seeds can be used as a substitute for non-renewable diesel. Methane is also considered as a renewable source of energy.

Adapted from the Wikipedia article Renewable resource, under the G. N. U. Free Documentation License. Please also see http://en.wikipedia.org/wiki

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The bridge is 470m long with a main span of 120m and features two large viewing and relaxation platforms, two rest areas, and a continuous all-weather canopy for the entire length of the bridge.

A canopy is supported by a secondary tensegrity structure. It is estimated that 550 tons of structural steel including 6.8 km of spiral strand cable are incorporated into the bridge.

The bridge is lit with a sophisticated LED lighting system which can be programmed to produce an array of different lighting effects. Depending on lighting configurations, 75%-100% of the power required is provided by solar energy.

All electrical work was done by Stowe Australia.

Adapted from the Wikipedia article Kurilpa Bridge, under the G. N. U. Free Documentation License. Please also see http://en.wikipedia.org/wiki

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Adapted from the Wikipedia article Solar gain, under the G. N. U. Free Documentation License. Please also see http://en.wikipedia.org/wiki

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The Florida Solar Energy Center conducts education and research into alternative energy sources including hydrogen, building construction, as well as solar thermal and photovoltaics.

Sewage

A local firm has developed a self-contained sewage system which recycles

water for use in boats, campers, remote camps. It sells for $15,000-$20,000. When it becomes more consumer priced, this could have a positive effect on local lagoon and estuary water quality.

Adapted from the Wikipedia article Environmental issues in Brevard County, under the G. N. U. Free Documentation License. Please also see http://en.wikipedia.org/wiki

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In standard photovoltaic applications trackers are used to minimize the angle of incidence between the incoming light and a photovoltaic panel. This increases the amount of energy produced from a fixed amount of installed power generating capacity. In standard photovoltaic applications, it is estimated that trackers are used in at least 85% of commercial installations greater than 1MW from 2009 to 2012.

In concentrated photovoltaic and concentrated solar thermal applications trackers are used to enable the optical components in the CPV and CSP systems. The optics in concentrated solar applications accept the direct component of sunlight light and therefore must be oriented appropriately to collect energy. Tracking systems are found in all concentrator applications because systems do not produce energy unless oriented toward the sun.

Adapted from the Wikipedia article Solar tracker, under the G. N. U. Free Documentation License. Please also see http://en.wikipedia.org/wiki

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While the value of RECs fluctuate, most sellers are legally obligated to “deliver” RECs to their customers within a few months of their generation date. Other organizations will sell as many RECs as possible and then use the funds to guarantee a specific fixed price per MWh generated by a future wind farm, for example, making the building of the wind farm a financially viable prospect. The income provided by RECs, and a long-term stabilized market for tags can generate the additional incentive needed to build renewable energy plants.

Adapted from the Wikipedia article Renewable Energy Certificates, under the G. N. U. Free Documentation License. Please also see http://en.wikipedia.org/wiki

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