PALM ISLANDS, DUBAI

tarih: 29/8/2007 Saat: 05:22 yer: - 0 Yorumlar - Yorum Yaz - Link

The Palm Islands in Dubai are the three largest artificial islands in the world. They are being constructed by Nakheel Properties, a property developer in the United Arab Emirates, who hired the Dutch dredging and marine contractor Van Oord, one of the world's specialists in land reclamation. The islands are The Palm Jumeirah, The Palm Jebel Ali and The Palm Deira.

The islands were commissioned by Sheikh Mohammed bin Rashid Al Maktoum in order to increase Dubai's tourism. Each settlement will be in the shape of a palm tree, topped with a crescent, and will have a large number of residential, leisure and entertainment centers. The Palm Islands are located off the coast of The United Arab Emirates in the Persian Gulf and will add 520 km of beaches to the city of Dubai.

The first two islands will comprise approximately 100 million cubic meters of rock and sand. Palm Deira will be composed of approximately 1 billion cubic meters of rock and sand. All materials will be quarried in the UAE. Between the three islands there will be over 100 luxury hotels, exclusive residential beach side villas and apartments, marinas, water theme parks, restaurants, shopping malls, sports facilities and health spas.

The creation of The Palm Jumeirah began in June 2001. Shortly after, The Palm Jebel Ali was announced and reclamation work began. In 2004, The Palm Deira, which will be almost as large in size as Paris, was announced. Palm Jumeirah is currently open for development. Construction will be completed over the next 10-15 years.

The Palm islands are technically artificial peninsulas constructed of sand dredged from the bottom of the Persian Gulf by the Dutch company Van Oord. The sand is sprayed by the dredging ships, which are guided by DGPS, onto the required area in a process known as rainbowing due to the way the sand arcs when sprayed. The outer edge of each Palm's encircling crescent is a large rock breakwater. The breakwater of the Palm Jumeirah has over 7 million tons of rock. Each rock was placed individually by a crane, signed off by a diver and given a GPS coordinate.

Palm Jumeirah

The Palm Jumeirah ( Coordinates: 25°06′28″N, 55°08′15″E ) consists of a trunk, a crown with 17 fronds, and a surrounding crescent island that forms an 11 kilometer-long breakwater. The island itself is 5 kilometers by 5 kilometers. It will add 78 kilometers to the Dubai coastline. The first phase of development on the Palm Jumeirah will create 4,000 residences with a combination of villas and apartments over the next 3 to 4 years.

Residents began moving into their Palm Jumeirah properties at the end of 2006, five years after land reclamation began, according to project developer Nakheel Properties. This signaled the end of phase one of construction, which includes approximately 1,400 villas on 11 of the fronds of the island and roughly 2,500 shoreline apartments in 20 buildings on the east side of the trunk.

According to Nakheel Properties officials, the process of adding 78 kilometers of beach is under way, while eight of the 32 hotels on The Palm Jumeirah have begun construction, including the Taj Exotica Resort and Spa, which is planned for completion in late 2008 or early 2009. The first phase of Atlantis, The Palm, is scheduled to be completed by December 2008.

The "Golden Mile", the strip of land located along the center of the trunk overlooking the canal, is set for completion in the first quarter of 2008. Construction has also begun on the Palm Monorail, which will take three years to complete and will serve as a transit system between the Gateway Station at the trunk of The Palm Jumeirah and the Atlantis Station on the crescent. (Emirates News Agency, WAM) On the Palm, construction workers have had to strengthen the sand base after a number of properties fell into the sea.

The Palm, Jebel Ali

The Palm, Jebel Ali began construction in October 2002 and is expected to be completed in mid 2008.The Jebel Ali is expected to accommodate 250,000 people and once it has been completed it will be encircled by the Dubai Waterfront project. The project, which will be 50 percent larger than the Palm Jumeriah, will include six marinas, a water theme park, 'Sea Village', homes built on stilts above the water, and boardwalks that circle the "fronds" of the "palm" and spell out an Arabic poem by Sheik Mohammed bin Rashid Al Maktoum:

Take wisdom from the wise

It takes a man of vision to write on water

Not everyone who rides a horse is a jockey

Great men rise to greater challenges

The Palm, Deira

The Palm Deira was announced for development on October 2004 and completion is expected in 2015, when it will become the largest of the three Palm Islands with 41 fronds. Projections indicate that construction will consume over a billion cubic meters of rock and sand.  According to the company Ten Real Estate, "The Palm Deira will cover 14 kilometers (8.7 miles) in length and 8.5 kilometers (5.3 miles) in width and have an area of 80 square kilometers (861 million square feet). It will consist of residential property, marinas, shopping malls, sports facilities, and clubs. The residential area will be located on the fronds and will contain 8,000 two-story town houses in three distinct styles - Premier Villas, Grand Villas and Vista Town Homes"

POWER GENERATOR

tarih: 29/8/2007 Saat: 05:21 yer: - 0 Yorumlar - Yorum Yaz - Link

In electricity generation, an electrical generator is a device that converts kinetic energy to electrical energy, generally using electromagnetic induction. The reverse conversion of electrical energy into mechanical energy is done by a motor, and motors and generators have many similarities. The source of mechanical energy may be a reciprocating or turbine steam engine, water falling through a turbine or waterwheel, an internal combustion engine, a wind turbine, a hand crank, or any other source of mechanical energy.

Electrostatic generators are used for scientific experiments requiring high voltages. Because of the difficulty of insulating machines producing very high voltages, electrostatic generators are made only with low power ratings and are never used for generation of commercially-significant quantities of electric power. Before the connection between magnetism and electricity was discovered, generators used electrostatic principles. The Wimshurst machine used electrostatic induction or "influence". Some electrostatic machines (such as the more modern Van de Graaff generator) uses either of two mechanisms:

• Charge transferred from a high-voltage electrode
• Charge created by the triboelectric effect using the separation of two insulators (the belt leaving the lower pulley)

   In 1831-1832 Michael Faraday discovered that a potential difference is generated between the ends of an electrical conductor that moves perpendicular to a magnetic field. He also built the first electromagnetic generator called the 'Faraday disc', a type of homopolar generator, using a copper disc rotating between the poles of a horseshoe magnet. It produced a small DC voltage, and large amounts of current.

Dynamo

The Dynamo was the first electrical generator capable of delivering power for industry. The dynamo uses electromagnetic principles to convert mechanical rotation into an alternating electric current. A dynamo machine consists of a stationary structure which generates a strong magnetic field, and a set of rotating windings which turn within that field. On small machines the magnetic field may be provided by a permanent magnet; larger machines have the magnetic field created by electromagnets.

The generator moves an electric current, but does not create electric charge, which is already present in the conductive wire of its windings. It is somewhat analogous to a water pump, which creates a flow of water but does not create the water inside. Other types of electrical generators exist, based on other electrical phenomena such as piezoelectricity, and magnetohydrodynamics. The construction of a dynamo is similar to that of an electric motor, and all common types of dynamos could work as motors.

An engine-generator is the combination of an electrical generator and an engine mounted together to form a single piece of equipment. This combination is also called an engine-generator set or a gen-set. In many contexts, the engine is taken for granted and the combined unit is simply called a generator.

In addition to the engine and generator, engine-generators generally include a fuel tank, an engine speed regulator and a generator voltage regulator. Many units are equipped with a battery and electric starter. Standby power generating units often include an automatic starting system and a transfer switch to disconnect the load from the utility power source and connect it to the generator.

Engine-generators are often used to supply electrical power in places where utility power is not available and in situations where power is needed only temporarily. Small generators are sometimes used to supply power tools at construction sites. Trailer-mounted generators supply power for temporary installations of lighting, sound ampliification systems, amusement rides etc.

Standby power generators are permanently installed and kept ready to supply power to critical loads during temporary interruptions of the utility power supply. Hospitals, communications service installations, sewage pumping stations and many other important facilities are equipped with standby power generators.

Small and medium generators are especially popular in third world countries to supplement grid power, which is often unreliable. Trailer-mounted generators can be towed to disaster areas where grid power has been temporarily disrupted.The generator can also be driven by the human muscle power (for instance, in the field radio station equipment).The generator voltage (volts), frequenc (Hz) and power (watts) ratings are selected to suit the load that will be connected.

Engine-generators are available in a wide range of power ratings. These include small, hand-portable units that can supply several hundred watts of power, hand-cart mounted units, as pictured above, that can supply several thousand watts and stationary or trailer-mounted units that can supply over a million watts. The smaller units tend to use gasoline (petrol) as a fuel, and the larger ones have various fuel types, including diesel, natural gas and propane (liquid or gas).

There are only a few portable three-phase generator models available in the US. Most of the portable units available are single phase power only and most of the three-phase generators manufactured are large industrial type generators.

Portable engine-generators may require an external power conditioner to safely operate some types of electronic equipment.

Hand portable emergency generators

Hand-held direct current generators supply energy to discharged car batteries. They are called emergency vehicle generators and includes batteries, to store energy.

A prefered hand-held generator is one that has an inverter. They are the smallest, quietest, and most fuel-efficient generators. Small portable generators have a standard A.C. alternator and run at a faster R.P.M. to generate power. Inverter models can run at slower RPMs to generate the power that is necessary, thus reducing the noise of the engine and making it more fuel-efficient. Inverter generators are best to power sensitive electronic devices such as computers and lights that use a ballast. The power output of an inverter is more stable and is equal to or better than household electrical power. Regular generators that do not have AVR (Automatic Voltage Regulation) can damage electronics such as computers and sound systems due to their varying voltage.

The mid-size stationary engine-generator pictured here is a 100 kVA set which produces 415 V at around 110 A per phase. It is powered by a 6.7 litre turbocharged Perkins Phaser 1000 Series engine, and consumes approximately 27 litres of fuel an hour, on a 400 litre tank. Diesel engines in the UK run on red diesel and rotate at 1500 rpm. This produces power at a frequency of 50 Hz, which is the frequency used in the UK. In areas where the power frequency is 60 Hz (United States), generators rotate at 1800 rpm or another even multiple of 60. Diesel engine-generator sets operated at their peak efficiency point can produce between 3 and 4 kilowatthours of electrical energy for each litre of diesel fuel consumed, with lower efficiency at part load.

MALTA

tarih: 29/8/2007 Saat: 05:20 yer: - 0 Yorumlar - Yorum Yaz - Link

Malta is a small and densely populated island nation comprising an archipelago of seven islands in the Mediterranean Sea. A country of Southern Europe, Malta lies south of Sicily, east of Tunisia, and north of Libya. The country's official languages are Maltese and English. Roman Catholicism is the most practised religion. The islands constituting the Maltese nation have been ruled by various powers and fought over for centuries, most recently the United Kingdom. Malta is a member of the Commonwealth of Nations. It has been a member state of the European Union (EU) since 2004 and it is currently the smallest EU country in both population and area.

Early settlements

                                   

After a period of Byzantine rule (fourth to ninth century) and a probable sack by the Vandals, the islands were conquered by the Arabs in AD 870. The Arabs, who generally tolerated the population's Christianity, introduced the cultivation of citrus fruits and cotton, and irrigation systems. Arab influence can be seen most prominently in the modern Maltese language, which also contains significant Romance influences, and is written in a variation of the Latin alphabet.

The period of Arab rule lasted until 1091, when the islands were taken by the Siculo-Normans. A century later the last Norman king, Tancredo di Lecce, appointed Margarito di Brindisi the first Count of Malta. Subsequent rulers included the Angevin, Hohenstaufen, and Aragonese, who reconstituted a County of Malta in 1283. The Maltese nobility was established during this period; some of it dating back to 1400. Around thirty-two noble titles remain in use today, of which the oldest is the Barony of Djar il-Bniet e Buqana.

Knights of Malta and Napoleon

In 1530, Holy Roman Emperor Charles V of Spain gave the islands to the Order of Knights of the Hospital of St John of Jerusalem in perpetual lease. (The Crown of Aragon had owned the islands as part of its Mediterranean empire for some time). These knights, a military religious order now known as the "Knights of Malta", had been driven out of Rhodes by the Ottoman Empire in 1522. They withstood a full-blown siege by the Ottoman Turks in 1565, at the time the greatest naval power in the Mediterranean sea. After this they decided to increase the fortifications, particularly in the inner-harbour area, where the new city of Valletta, named after Grand Master Jean de la Valette, was built.

       

Their reign ended when Malta was captured by Napoleon en route to his expedition of Egypt during the French Revolutionary Wars in 1798. As a ruse, Napoleon asked for safe harbour to resupply his ships, and then turned his guns against his hosts once safely inside Valletta. The Grandmaster knew that he could only allow a few ships at a time to enter the harbour, due to the Treaty of Trent. Grand Master Ferdinand von Hompesch zu Bolheim capitulated, and Napoleon stayed in Malta for a few days, during which he systematically looted the movable assets of the Order, and established an administration controlled by his nominees. He then sailed for Egypt, leaving a substantial garrison in Malta.

The occupying French forces were unpopular, however, due particularly to their negative attitude towards religion. The financial reforms and the religious reforms did not go down well with the citizens. The Maltese rebelled against them, and the French were forced behind the fortifications. Great Britain, along with the Kingdom of the Two Sicilies, sent munitions and aid to the rebels. Britain also sent her navy, which instigated a blockade of the islands. The isolated French forces, under General Claude-Henri Belgrand de Vaubois, surrendered in 1800, and the island became a British Dominion, being presented by several Maltese leaders to Sir Alexander Ball.

Their reign ended when Malta was captured by Napoleon en route to his expedition of Egypt during the French Revolutionary Wars in 1798. As a ruse, Napoleon asked for safe harbour to resupply his ships, and then turned his guns against his hosts once safely inside Valletta. The Grandmaster knew that he could only allow a few ships at a time to enter the harbour, due to the Treaty of Trent. Grand Master Ferdinand von Hompesch zu Bolheim capitulated, and Napoleon stayed in Malta for a few days, during which he systematically looted the movable assets of the Order, and established an administration controlled by his nominees. He then sailed for Egypt, leaving a substantial garrison in Malta.

The occupying French forces were unpopular, however, due particularly to their negative attitude towards religion. The financial reforms and the religious reforms did not go down well with the citizens. The Maltese rebelled against them, and the French were forced behind the fortifications. Great Britain, along with the Kingdom of the Two Sicilies, sent munitions and aid to the rebels. Britain also sent her navy, which instigated a blockade of the islands. The isolated French forces, under General Claude-Henri Belgrand de Vaubois, surrendered in 1800, and the island became a British Dominion, being presented by several Maltese leaders to Sir Alexander Ball.

British rule and World War II

In 1814, as part of the Treaty of Paris, Malta officially became a part of the British Empire, and was used as a shipping way-station and fleet headquarters. Malta's position half-way between Gibraltar and the Suez Canal proved to be its main asset during these years, and it was considered to be a most important stop on the way to India.

Malta joined the European Union on May 1, 2004. Following the conclusions of the European Council of 21 to 22 June 2007 it will be joining the Eurozone in 2008.

Geography

Contrary to popular belief, the south of Malta is not Europe's most southern point; that distinction belongs to the Greek island of Gavdos. It is even clear that the whole famous Greek island of Crete is more southern than any point of Malta.

FIBER TECHNOLOGY

tarih: 28/8/2007 Saat: 05:20 yer: - 0 Yorumlar - Yorum Yaz - Link

FIBER TECHNOLOGY

Fiber or fibre is a class of materials that are continuous filaments or are in discrete elongated pieces, similar to lengths of thread. Fibers are of great importance in the biology of both plants and animals, for holding tissues together. Human uses for fibers are diverse. They can be spun into filaments, thread, string or rope. They can be used as a component of composite materials. They can also be matted into sheets to make products such as paper or felt. Fibers are often used in the manufacture of other materials.

Natural fibers include those produced by plants, animals, and geological processes. They can be classified according to their origin:

• Vegetable fibers are generally based on arrangements of cellulose, often with lignin: examples include cotton, hemp jute, flax, ramie, and sisal. Plant fibers serve in the manufacture of paper and cloth.
• Wood fiber, distinguished from vegetable fiber, is from tree sources. Forms include groundwood, thermomechanical pulp (TMP) and bleached or unbleached kraft or sulfite pulps. Kraft and sulfite, also called sulphite, refer to the type of pulping process used to remove the lignin bonding the original wood structure, thus freeing the fibers.
• Animal fibers consist largely of particular proteins. Instances are spider silk, sinew, catgut and hair (including wool).
• Mineral fibers comprise asbestos. Asbestos is the only naturally occurring long mineral fiber. Short, fiber-like minerals include wollastinite, attapulgite and halloysite.

Man-made fibers may come from natural raw materials or from synthetic chemicals. Many types of fiber are manufactured from natural cellulose, including rayon, modal, and the more recently developed Lyocell. Cellulose-based fibers are of two types, regenerated or pure cellulose such as from the cupro-ammonium process and modified or derivitized cellulose such as the cellulose acetates.

Mineral fibers

The most well-known mineral fibers are glass and metal fibers.

• Fiberglass made from specific glass formulas and optical fiber, made from purified natural quartz, are also man-made fibers that come from natural raw materials.
• Metallic fibers can be drawn from ductile metals such as copper, gold or silver and extruded or deposited from more brittle ones such as nickel, aluminum or iron.
• Carbon fibers are often based on carbonised polymers, but the end product is pure carbon.

Polymer fibers

• Polymer fibers are a subset of man-made fibers, which are based on synthetic chemicals (often from petrochemical sources) rather than arising from natural materials by a purely physical process. Such fibers are made from:

  • polyamide nylon,
  • PET or PBT polyester
  • phenol-formaldehyde (PF)
  • polyvinyl alcohol fiber (PVOH)
  • polyvinyl chloride fiber (PVC)
  • polyolefins (PP and PE)
  • acrylic polymers, pure polyacrylonitrile PAN fibers are used to make carbon fiber by roasting them in a low oxygen environment. Traditional acrylic fiber is used more often as a synthetic replacement for wool. Carbon fibers and PF fibers are noted as two resin-based fibers that are not thermoplastic, most others can be melted.
  • Aromatic polyamids such as Twaron, Kevlar and Nomex thermally degrade at high temperatures and do not melt. These fibers have strong bonding between polymer chains
  • polyethylene (PE), eventually with extremely long chains / HMPE (e.g. Dyneema or Spectra).
  • Elastomers can even be used, e.g. spandex although urethane fibers are starting to replace spandex technology.
  • polyurethane fiber

• Coextruded fibers have two distinct polymers forming the fiber, usually as a core-sheath or side-by-side. Coated fibers exist such as nickel-coated to provide static elimination, silver-coated to provide anti-bacterial properties and aluminum-coated to provide radar chaff. Radar chaff is actually a spool of continuous glass tow that has been aluminum coated. An aircraft-mounted high speed cutter chops it up as it spews from a moving aircraft to foil radar signals.

Microfibers

Micro fibers in textiles refer to sub-denier fiber (such as polyester drawn to 0.5 dn). Denier and Detex are two measurements of fiber yield based on weight and length. If the fiber density is known you also have a fiber diameter, otherwise it is simpler to measure diameters in micrometres. Microfibers in technical fibers refer to ultrafine fibers (glass or meltblown thermoplastics) often used in filtration. Newer fiber designs include extruding fiber that splits into multiple finer fibers. Most synthetic fibers are round in cross-section, but special designs can be hollow, oval, star-shaped or trilobal. The latter design provides more optically reflective properties. Synthetic textile fibers are often crimped to provide bulk in a woven, nonwoven or knitted structure. Fiber surfaces can also be dull or bright. Dull surfaces reflect more light while bright tends to transmit light and make the fiber more transparent.

Very short and/or irregular fibers have been called fibrils. Natural cellulose, such as cotton or bleached kraft show smaller fibrils jutting out and away from the main fiber structure. 

SOLAR POWER

tarih: 28/8/2007 Saat: 05:18 yer: - 0 Yorumlar - Yorum Yaz - Link

Solar power (also known as solar energy) is a source of energy that uses radiation emitted by the Sun. It is a renewable energy source that has been used in many traditional technologies for centuries. It is also in widespread use where other power supplies are absent, such as in remote locations and in space.

Solar energy is currently used in a number of applications:

• Heat (hot water, building heat, cooking)
• Electricity generation (photovoltaics, heat engines)
• Transportation (solar car)
• Desalination of seawater
• Photosynthesis by plants

Solar radiation reaches the Earth's upper atmosphere at a rate of 1366 watts per square meter (W/m²).The first map shows how the solar energy varies in different latitudes.

While traveling through the atmosphere, 6% of the incoming solar radiation (insolation) is reflected and 16% is absorbed resulting in a peak irradiance at the equator of 1,020 W/m².Average atmospheric conditions (clouds, dust, pollutants) further reduce insolation by 20% through reflection and 3% through absorption.Atmospheric conditions not only reduce the quantity of insolation reaching the Earth's surface but also affect the quality of insolation by diffusing incoming light and altering its spectrum.

The second map shows the average global irradiance calculated from satellite data collected from 1991 to 1993. For example, in North America the average insolation at ground level over an entire year (including nights and periods of cloudy weather) lies between 125 and 375 W/m² (3 to 9 kWh/m²/day).This represents the available power, and not the delivered power. At present, photovoltaic panels typically convert about 15% of incident sunlight into electricity; therefore, a solar panel in the contiguous United States on average delivers 19 to 56 W/m² or 0.45 - 1.35 kWh/m²/day.

The dark disks in the third map on the right are an example of the land areas that, if covered with 8% efficient solar panels, would produce slightly more energy in the form of electricity than the total world primary energy supply in 2003. While average insolation and power offer insight into solar power's potential on a regional scale, locally relevant conditions are of primary importance to the potential of a specific site.

After passing through the Earth's atmosphere, most of the sun's energy is in the form of visible and infrared radiation. Plants use solar energy to create chemical energy through photosynthesis. Humans regularly use this energy burning wood or fossil fuels, or when simply eating the plants.

A recent concern is global dimming, an effect of pollution that is allowing less sunlight to reach the Earth's surface. It is intricately linked with pollution particles and global warming, and it is mostly of concern for issues of global climate change, but is also of concern to proponents of solar power because of the existing and potential future decreases in available solar energy. The order of magnitude is about 4% less solar energy available at sea level over the timeframe of 1961–90, mostly from increased reflection from clouds back into space.

Many types of technology have been developed to make use of solar radiation. Some of these technologies make direct use of the solar energy (e.g. to provide light, heat, etc.), while others produce electricity

Solar design in architecture involves the use of appropriate solar technologies to maintain a building’s environment at a comfortable temperature through the sun's daily and annual cycles. It may do this by storing solar energy as heat in the walls of a building, which then acts to heat the building at night. Another approach is to keep the interior cool during a hot day by designing in natural convection through the building’s interior.

Solar hot water systems use sunlight to heat water. Solar hot water systems were used extensively in the United States up to the 1920s until replaced by relatively cheap and more reliable conventional heating fuels. The economic advantage of conventional heating fuels has varied over time resulting in periodic interest in solar hot water; however, solar hot water and heating technologies have yet to show the sustained momentum they lost in the 1920s. That being said, the recent spikes and erratic availability of conventional fuels have resulted in a renewed interest in solar heating technologies.

On a technical level, solar water heating is particularly appropriate for low temperature applications (100-150F). This advantage has been successfully applied to heating swimming pools where solar water heating can economically increase pool use. Solar water heating is also used in stand alone or hybrid domestic water heating systems.

Solar water heating systems are composed of solar thermal collectors, a storage tank and a circulation loop. The three basic classifications of solar water heaters are:

• Batch systems which consist of a tank that is directly heated by sunlight. These are the oldest and simplest solar water heater designs, however; the exposed tank can be vulnerable to cooldown.
• Active systems which use pumps to circulate water or a heat transfer fluid.
• Passive systems which circulate water or a heat transfer fluid by natural circulation. These are also called thermosiphon systems.

A Trombe wall is a passive solar heating and ventilation system consisting of an air channel sandwiched between a window and a sun-facing wall. Sunlight heats the air space during the day causing natural circulation through vents at the top and bottom of the wall and storing heat in the thermal mass. During the evening the Trombe wall radiates stored heat.

A transpired collector is a perforated sun-facing wall. The wall absorbs sunlight and pre-heats air up 40F as it is drawn into the building's ventilation system. These systems are inexpensive and pay for themselves within 3-12 years in offset heating costs

A solar box cooker traps the sun's energy in an insulated box; such boxes have been successfully used for cooking, pasteurization and fruit canning. Solar cooking is helping many developing countries, both reducing the demands for local firewood and maintaining a cleaner breathing environment for the community.

The first known western solar oven is attributed to Horace de Saussure in 1767, which impressed Sir John Herschel enough to build one for cooking meals on his astronomical expedition to the Cape of Good Hope in Africa in 1830. Today, there are many different designs in use around the world.

Daylighting is a passive solar method of using natural light to provide illumination. Daylighting directly offsets energy use in electric lighting systems and indirectly offsets energy use through a reduction in cooling load.^[14] Although difficult to quantify, the use of natural light also offers physiological and psychological benefits compared to conventional lighting.

Daylight features include building orientation, window orientation, exterior shading, sawtooth roofs, clerestory windows, light shelves, skylights and light tubes. These features may be incorporated in existing structures but are most effective when integrated in a solar design package which accounts for factors such as glare, heat gain, heat loss and time-of-use. Architectural trends increasingly recognize daylighting as a cornerstone of sustainable design.

Hybrid solar lighting (HSL) is an active solar method of using natural light to provide illumination. Hybrid solar lighting systems collect sunlight using focusing mirrors that track the sun. The collected light is transmitted via optical fibers into a building's interior to supplement conventional lighting.

Daylight saving time (DST) can be seen as a method of utilising solar energy by matching available sunlight to the hours of the day in which it is most useful. In 2001 this was estimated to reduce peak demand in California by 35–70 MW (0.08%–0.16%) in June through August, though total electricity use was unaffected. However, there is some question whether these estimates are valid. In 2000 when parts of Australia began DST in late winter, overall electricity consumption did not decrease, but the peak load increased

Solar cells, also referred to as photovoltaic cells, are devices or banks of devices that use the photovoltaic effect of semiconductors to generate electricity directly from sunlight. Until recently, their use has been limited because of high manufacturing costs. One cost effective use has been in very low-power devices such as calculators with LCDs. Another use has been in remote applications such as roadside emergency telephones, remote sensing, cathodic protection of pipe lines, and limited "off grid" home power applications. A third use has been in powering orbiting satellites and spacecraft.

To take advantage of the incoming electromagnetic radiation from the sun, solar panels can be attached to each house or building. The panels should be mounted perpendicular to the arc of the sun to maximize usefulness. The easiest way to use this electricity is by connecting the solar panels to a grid tie inverter. However, these solar panels may also be used to charge batteries or other energy storage device. Solar panels produce more power during summer months because they receive more sunlight. The cost payback time may take over 10 years depending on the cost of grid electricity and tax rebates.

Total peak power of installed PV is around 6,000 MW as of the end of 2006. Installed PV is projected to increase to over 9,000 MW in 2007. This is only one part of solar-generated electric power.

Declining manufacturing costs (dropping at 3 to 5% a year in recent years) are expanding the range of cost-effective uses. The average lowest retail cost of a large photovoltaic array declined from $7.50 to $4 per watt between 1990 and 2005.With many jurisdictions now giving tax and rebate incentives, solar electric power can now pay for itself in five to ten years in many places. "Grid-connected" systems - those systems that use an inverter to connect to the utility grid instead of relying on batteries - now make up the largest part of the market.

In 2003, worldwide production of solar cells increased by 32%. Between 2000 and 2004, the increase in worldwide solar energy capacity was an annualized 60%. 2005 was expected to see large growth again, but shortages of refined silicon have been hampering production worldwide since late 2004. Analysts have predicted similar supply problems for 2006 and 2007.