Wednesday, March 13, 2013

Advantages of Solar Energy


by Nick Gromicko

 
Solar energy offers considerable advantages over conventional energy systems by nullifying flaws in those systems long considered to be unchangeable. Solar power for home energy production has its flaws, too, which are outlined in another article, but they're dwarfed by the advantages listed below.
 
Solar energy is a great choice
The following are advantages of solar energy:
  • Raw materials are renewable and unlimited. The amount of available solar energy is staggering -- roughly 10,000 times that currently required by humans -- and it’s constantly replaced. A mere 0.02% of incoming sunlight, if captured correctly, would be sufficient to replace every other fuel source currently used.
Granted, the Earth does need much of this solar energy to drive its weather, so let’s look only at the unused portion of sunlight that is reflected back into space, known as the albedo. Earth’s average albedo is around 30%, meaning that roughly 52 petawatts of energy is reflected by the Earth and lost into space every year. Compare this number with global energy-consumption statistics.  Annually, the energy lost to space is the combined equivalent of 400 hurricanes, 1 million Hoover Dams, Great Britain's energy requirement for 250,000 years, worldwide oil, gas and coal production for 387 years, 75 million cars, and 50 million 747s running perpetually for one year (not to mention 1 million fictional DeLorean time machines!). 
  • Solar power is low-emission. Solar panels produce no pollution, although they impose environmental costs through manufacture and construction. These environmental tolls are negligible, however, when compared with the damage inflicted by conventional energy sources:  the burning of fossil fuels releases roughly 21.3 billion metric tons of carbon dioxide into the atmosphere annually.  
  • Solar power is suitable for remote areas that are not connected to energy grids. It may come as a surprise to city-dwellers but, according to Home Power Magazine, as of 2006, 180,000 houses in the United States were off-grid, and that figure is likely considerably higher today. California, Colorado, Maine, Oregon, Vermont and Washington have long been refuges for such energy rebels, though people live off the grid in every state. While many of these people shun the grid on principle, owing to politics and environmental concerns, few of the world’s 1.8 billion off-the-gridders have any choice in the matter. Solar energy can drastically improve the quality of life for millions of people who live in the dark, especially in places such as Sub-Saharan Africa, where as many as 90% of the rural population lacks access to electricity. People in these areas must rely on fuel-based lighting, which inflicts significant social and environmental costs, from jeopardized health through Rural, off-grid homes are excellent applications for solar powercontamination of indoor air, to limited overall productivity.  
  • Solar power provides green jobs. Production of solar panels for domestic use is becoming a growing source of employment in research, manufacture, sales and installation.
  • Solar panels contain no moving parts and thus produce no noise. Wind turbines, by contrast, require noisy gearboxes and blades.
  • In the long run, solar power is economical. Solar panels and installation involve high initial expenses, but this cost is soon offset by savings on energy bills.  Eventually, they may even produce a profit on their use.
  • Solar power takes advantage of net metering, which is the practice of crediting homeowners for electricity they produce and return to the power grid. As part of the Energy Policy Act of 2005, public electric utilities are required to make available, upon request, net metering to their Manhattan, and much of the northeast USA, goes dark in August, 2003customers. This practice offers an advantage for homeowners who use solar panels (or wind turbines or fuel cells) that may, at times, produce more energy than their homes require. If net metering is not an option, excess energy may be stored in batteries.
  • Solar power can mean government tax credits. U.S. federal subsidies credit up to 30% of system costs, and each state offers its own incentives. California, blessed with abundant sunshine and plagued by high electric rates and an over-taxed grid, was the first state to offer generous renewable-energy incentives for homes and businesses.
  • Solar power is reliable. Many homeowners favor solar energy because it is virtually immune to potential failings of utility companies, mainly in the form of political or economic turmoil, terrorism, natural disasters, or brownouts due to overuse. The Northeast Blackout of 2003 unplugged 55 million people across two countries, while rolling blackouts are a part of regular life in some South Asian countries, and occasionally in California and Texas.
  • Solar power conserves foreign energy expenditures. In many countries, a large percentage of earnings is used to pay for imported oil for power generation. The United States alone spends $13 million per hour on oil, much of which comes from Persian Gulf nations. As oil supplies dwindle and prices rise in this politically unstable region, these problems continue to catalyze the expansion of solar power and other alternative-energy systems.
In summary, solar energy offers advantages to conventional fossil fuels and other renewable energy systems.


From Advantages of Solar Energy - InterNACHI http://www.nachi.org/advantages-solar-energy.htm#ixzz2NStULIDs

Tuesday, March 5, 2013

Central Air-Conditioning System Inspection



by Nick Gromicko and Rob London
 
 
A building's central air-conditioning system must be periodically inspected and maintained in order to function properly. While an annual inspection performed by a trained professional is recommended, homeowners can do a lot of the work themselves by following the tips offered in this guide.Exterior Condenser Unit
 
Clean the Exterior Condenser Unit and Components
 
The exterior condenser unit is the large box located on the side of the building that is designed to push heat from the inside of the building to the outdoors. Inside of the box are coils of pipe that are surrounded by thousands of thin metal "fins" that allow the coils more surface area to exchange heat. Follow these tips when cleaning the exterior condenser unit and its inner components -- after turning off power to the unit!
  • Remove any leaves, spider webs and other debris from the unit's exterior. Trim foliage back several feet from the unit to ensure proper air flow.
  • Remove the cover grille to clean any debris from the unit's interior. A garden hose can be helpful for this task.
  • Straighten any bent fins with a tool called a fin comb.
  • Add lubricating oil to the motor. Check your owner’s manual for specific instructions.
  • Clean the evaporator coil and condenser coil at least once a year.  When they collect dirt, they may not function properly.
Inspect the Condensate Drain Line
 
Condensate drain lines collect condensed water and drain it away from the unit.  They are located on the side of the inside fan unit. Sometimes there are two drain lines—a primary drain line that’s built into the unit, and a secondary drain line that can drain if the first line becomes blocked. Homeowners can inspect the drain line by using the following tips, which take very little time and require no specialized tools:
  • Inspect the drain line for obstructions, such as algae and debris. If the line becomes blocked, water will back up into the drain pan and overflow, potentially causing a safety hazard or water damage to your home.
  • Make sure the hoses are secured and fit properly.
Clean the Air Filter
The air filter slides out for easy replacement
 
Air filters remove pollen, dust and other particles that would otherwise circulate indoors. Most filters are typically rectangular in shape and about 20 inches by 16 inches, and about 1 inch thick. They slide into the main ductwork near the inside fan unit. The filter should be periodically washed or replaced, depending on the manufacturer’s instructions. A dirty air filter will not only degrade indoor air quality, but it will also strain the motor to work harder to move air through it, increasing energy costs and reducing energy efficiency. The filter should be replaced monthly during heavy use during the cooling seasons. You may need to change the filter more often if the air conditioner is in constant use, if building occupants have respiratory problems,if  you have pets with fur, or if dusty conditions are present. 
 
Cover the Exterior Unit
 
When the cooling season is over, you should cover the exterior condenser unit in preparation for winter. If it isn’t being used, why expose it to the elements? This measure will prevent ice, leaves and dirt from entering the unit, which can harm components and require additional maintenance in the spring. A cover can be purchased, or you can make one yourself by taping together plastic trash bags. Be sure to turn the unit off before covering it.
Close the Air-Distribution Registers
 
Air-distribution registers are duct openings in ceilings, walls and floors where cold air enters the room. They should be closed after the cooling season ends in order to keep warm air from back-flowing out of the room during the warming season. Pests and dust will also be unable to enter the ducts during the winter if the registers are closed. These vents typically can be opened or closed with an adjacent lever or wheel.  Remember to open the registers in the spring before the cooling season starts.  Also, make sure they are not blocked by drapes, carpeting or furniture.
 
In addition, homeowners should practice the following strategies in order to keep their central air conditioning systems running properly:
  • Have the air-conditioning system inspected by a professional each year before the start of the cooling season.
  • Reduce stress on the air conditioning system by enhancing your home’s energy efficiency. Switch from incandescent lights to compact fluorescents, for instance, which produce less heat.
 
In summary, any homeowner can perform periodic inspections and maintenance to their home's central air-conditioning system.


From Central Air-Conditioning System Inspection - InterNACHI http://www.nachi.org/central-air-conditioning-system-inspection.htm#ixzz2MiE1HS2H