What are Photovoltaics


Photovoltaic solar cells, which directly convert sunlight into electricity, are made of semiconducting materials. The simplest photovoltaic cells power watches and calculators and the like, while more complex systems can light houses and provide power to the electrical grid.

August 31st, 2005 - Posted in Photovoltaics, Solar Power News | | 0 Comments

Solar Energy Basics

Solar Energy Basics

Sunlight—solar energy—can be used to generate electricity, provide hot water, and to heat, cool, and light buildings.

Photovoltaic (solar cell) systems convert sunlight directly into electricity. A solar or PV cell consists of semiconducting material that absorbs the sunlight. The solar energy knocks electrons loose from their atoms, allowing the electrons to flow through the material to produce electricity. PV cells are typically combined into modules that hold about 40 cells. About 10 of these modules are mounted in PV arrays. PV arrays can be used to generate electricity for a single building or, in large numbers, for a power plant. A power plant can also use a concentrating solar power system, which uses the sun’s heat to generate electricity. The sunlight is collected and focused with mirrors to create a high-intensity heat source. This heat source produces steam or mechanical power to run a generator that creates electricity.

Solar water heating systems for buildings have two main parts: a solar collector and a storage tank. Typically, a flat-plate collector—a thin, flat, rectangular box with a transparent cover—is mounted on the roof, facing the sun. The sun heats an absorber plate in the collector, which, in turn, heats the fluid running through tubes within the collector. To move the heated fluid between the collector and the storage tank, a system either uses a pump or gravity, as water has a tendency to naturally circulate as it is heated. Systems that use fluids other than water in the collector’s tubes usually heat the water by passing it through a coil of tubing in the tank.

Many large commercial buildings can use solar collectors to provide more than just hot water. Solar process heating systems can be used to heat these buildings. A solar ventilation system can be used in cold climates to preheat air as it enters a building. And the heat from a solar collector can even be used to provide energy for cooling a building.

A solar collector is not always needed when using sunlight to heat a building. Some buildings can be designed for passive solar heating. These buildings usually have large, south-facing windows. Materials that absorb and store the sun’s heat can be built into the sunlit floors and walls. The floors and walls will then heat up during the day and slowly release heat at night—a process called direct gain. Many of the passive solar heating design features also provide daylighting. Daylighting is simply the use of natural sunlight to brighten up a building’s interior.

August 22nd, 2005 - Posted in Solar Energy News | | 0 Comments

ICP Solar 20750 SolarPRO Plug’n'Play 75-Watt Kit.

ICP Solar 20750 SolarPRO Plug’n'Play 75-Watt Kit.

With Super easy set-up installation takes only seconds! Plug’n'Play technology also allows multiple panels to be connected with no wiring. Includes 7 Amp charge regulator. LED display indicates current charging level. Built-in discharge protection. Frame is waterproof and resistant to rust and shock.

August 17th, 2005 - Posted in Solar Energy Products | | 0 Comments

La Crosse Technology WS-2010 Professional Wireless Weather Station

Exceptional as a gift, this professional wireless weather station is a meteorologist’s dream. The stylish main base unit, with built-in desk stand and hanging notch, receives and simultaneously displays data (in metric or U.S.) from the included four remote sensors, three of which are solar-powered with rechargeable lithium battery backup for measuring wind, rain, and outdoor temperature and humidity. The fourth sensor measures indoor temperature, humidity, and air pressure. Symbolic display of forecasts, graphical display of air pressure changes over the last 24 hours, and storing of minimum and maximum measured values for all sensors are just a few of the options shown on the base unit. Up to 39 alarms may be programmed for frost warnings, storm warnings, etc. Boaters or retired sailors will appreciate the ability to check wind speed in miles per hour, knots, meters per second, kilometers per hour, Beaufort scale, or wind direction in a 5° resolution instead of wind speed. Gardeners can keep track of rainfall for the previous hour, previous 24 hours, and total amount since the last reset. Hardware is included for mounting the various sensors. La Crosse weather instruments are automatically calibrated daily to the atomic time standard of the National Institute of Standards and Technology, via radio station WWVB in Colorado. This weather station is covered by a one-year warranty, excluding interference problems. Six AA batteries are required.–Ann Bieri

Product Description
With 4 separate sensors, including solar-powered outdoor sensors for temperature and humidity, rainfall and wind direction, this La Crosse professional weather station gives you a continuous, detailed and accurate report of conditions in your specific location. The station indicates the weather forecast—displayed as an icon (like the symbols used in the news)—as well as air pressure trends and a 24-hr. bar chart history. The wireless rain gauge tracks total rainfall, along with rainfall amounts for the last hour and 24 hrs. The wind gauge tracks speed and direction, displaying the information on an easy-to-read compass. The station also simultaneously displays indoor temperature, humidity and pressure, outdoor temperature and humidity, and minimum/maximum (highs and lows) data for all readings with time and date recorded. Features US/metric select for all data, manual set time and date, data receiving from as many as 9 transmitters (additional sensors sold separately) and a transmission range of up to 330′. Includes display, 4 remote sensors (1 battery-operated indoor plus 3 solar-powered outdoor), a rechargeable Lithium backup battery for solar-powered sensors, and mounting hardware. Wall hanging or free standing. Weather station (display): 8-1/2Lx1-1/4Wx6-1/2H.

August 10th, 2005 - Posted in Solar Energy Products | | 0 Comments