Monday, March 12, 2012

Programmable thermostats make it easy for homeowners to save energy and still come home (or wake up) to a comfortable house.

Following  our "House Posts", enjoy it.

Another effect that we should discuss is how your furnace or boiler delivers heat to your house. Most furnaces and boilers run either at full fire or off. When the combustion cycle starts, a certain amount of heat is used to warm up the heat exchanger and the duct or pipes. When the furnace or boiler shuts off, much of this heat will be lost.
(Having your ducts taped and insulated will help minimize this.) Any energy-saving strategy should also try to minimize the cycling of your heating system.

The most energy-saving alternative is to let your house become as cold as possible while you’re not home. What’s “as cold as possible”?
Don’t allow anything fragile (water pipes, for example) to freeze.
Allow just enough time for your heating system to bring the house temperature to its set point the moment you walk in the door.

But wait, there’s another complication. Even though the air temperature in your house may be at the perfect set point, you may feel less comfortable under these conditions. That’s because the surfaces in your house will probably be colder than if you had left the temperature set point higher. Cold surfaces will make you feel colder—not just because of touch (conduction), but also because of radiation.

The strategy of saving energy by allowing your house to drop in temperature while it’s unoccupied makes perfect sense. Programmable thermostats can “learn” how fast your house heats up and bring the temperature to the set point with little cycling. Also: Web-enabled thermostats, where you can access your home system from any Internet-connected computer, offer even more convenience for people with varying schedules.

Monday, March 5, 2012

Tweaking an Solar Hot Water (SHW) System

An amazing article that we saw in "Home Power Magazine", Enjoy it.

Two situations: 

I recently had a solar hot water (SHW) system installed on my house. It is a closed-loop, evacuated-tube system with a heat exchanger in the storage tank. The differential control (a Caleffi Solar Plus) provides variable pump speed control. Currently, it is using factory defaults for the conditions that determine pump speed. The system has four temperature sensors and a data logger, which help me keep tabs on its function.
I like the idea of a variable-speed pump because it seems like it can add efficiency to an SHW system—just like an MPPT controller does to solar-electric systems. That said, I am not sure what conditions drive the efficiency of the SHW system. Should the control be set for lower flows and higher temperatures, or higher flows and lower temperatures? I know there is more heat transfer at the exchanger with a higher temperature difference between the transfer fluid and tank water, but I am not sure how that balances with the collectors’ lower efficiencies at higher temperatures.
Is there a reference I can use to figure this out? I am not looking for specific numbers—more like basic explanations of relationships between the parts of the system and what to look for as a sign of how well an SHW system is performing. Perhaps it’s something like checking transfer-fluid temperature drop across the heat exchanger versus the temperature rise at the collector.

Jack Herndon • Seattle, Washington

An ideal collector loop of any SHW system would operate at a difference in temperature of just a few degrees between the inlet and outlet temperatures of the collectors. The higher this differential, the more heat is lost to the outside atmosphere.
This loss is dependent on the outside temperature. Although evacuated tubes are more resistant to heat loss, they are not immune to it. If you’re seeing a temperature difference of 50°F or greater, your system is suffering from a low flow rate problem. A system with a 20°F difference is much closer to operating at an “ideal” temperature.
The ideal is a compromise between the lower inlet/outlet differential to minimize heat loss, and a high-enough differential to prevent the control from short-cycling. Short-cycling will occur with too high of a flow rate and will be noticeable—the system will turning on and off excessively. Turning on and off is normal in the early morning and late afternoon and in cloudy weather, but shouldn’t happen in mid- day bright sun.
Chuck Marken • Home Power solar thermal editor
The Answer: 

Thermostat Dilemma
Is it more energy efficient to turn off your home’s heat when you’re going to be gone all day, or to leave it at a slightly lowered set point? I realize that this is likely a complex calculation involving volume of space, outside temperatures, building envelope and insulation, number of degrees in drop and recovery, elapsed time, type and cost of heating fuel, etc. But perhaps there are some general rules or simplified formulas that can direct a homeowner on the best approach.

Temperature Differentials, With & Without Heat Exchangers

The short answer is that leaving your thermostat at a very low set point will almost always result in lower energy consumption. The long answer follows.
For most residential heating systems, the thermostat controls the heating system to maintain the set point (the temperature you set). It does this by turning the heating system on and off. As you would expect, the room temperature will fluctuate from the set point, unless you allow the heating system to cycle on and off very quickly, which will prematurely age your equipment.
During cold weather, your house is continually losing heat to the outdoors. It does this in several ways. Heat is lost by conduction through the surfaces of the house; warm air exits the house while cold air enters (infiltration); and to a lesser extent, your house radiates heat outward. Of course, it gets more complicated, since your house has a great many parts, each of which have different thermal conductivities, thermal capacities, and radiative properties.
The net effect of all this complicated heat transfer is that a typical house will (almost always) lose more heat when the inside temperature becomes higher relative to outside. I say “almost always” because it’s possible to have net heat gain on a cold day if it’s very sunny, and your house is well-insulated and sealed.

Monday, February 13, 2012

Heli-Cycling on High

No Mountain High Enough


The magical kingdom of Nepal is, without a doubt, one of the most storied destina- tions in the world, and a mecca for adven- ture travelers of every stripe. What better way to see this exotic land than on a mountain bike? Well, actually, there is a better way—on a mountain bike that’s transported by helicopter to a highland pass, allowing you to cruise downhill through some of the most spectacular ter- rain on earth. You can now ride through Nepal’s magnificent scenery while avoid- ing the lung-busting uphill rides that would make the trip impossible for all but a hand- ful of oxygen-carrying elite athletes.
Most trips to Nepal begin in Kathmandu, the country’s capital and largest (and noisiest) city. Heli-cycling programs organized by qualified tour operators who know the terrain are definitely the way to experi- ence this activity; some operators have relatively short 1-day packages, while oth- ers offer longer excursions of several days. Thrill-seekers opting for longer tours are able to stop in remote teahouses for breaks, and stay overnight in lodges nes- tled in isolated villages.

If what you seek is adventure on the road less traveled, you’ll find it here. Many of the spots visited by heli-cyclers are tiny hamlets, difficult to reach even by four- wheel-drive vehicles. The landscape is rich and varied: Icy, snow-capped mountain ranges give way to dense alpine forests,semi-arid steppes, surging rivers, lush farmland, and golden rice paddies. And for sheer death-defying thrills, try crossing a swinging suspension bridge on a windy day with a full pack and a mountain bike— not for the faint of heart.

It’s not all hard work and sweat, how- ever. Bikers make frequent stops to sam- ple local foods and teas, including the region’s apple ciders and brandies. In addition, there are hot spring pools along some routes that allow bone-weary riders a chance to soothe their aching bodies. And at the end of your journey, the sights and sounds of Kathmandu are yours to explore. —ML

Wednesday, January 18, 2012

Breast surgery

Breast surgery is defined as any medical procedure that penetrates beyond the surface of breast skin. Breast surgery ranges from procedures as limited as a needle biopsy, to something as complex as microsurgical post-mastectomy breast reconstruction.

Breast surgery can be defined in two broad categories:

  • • Procedures to diagnose and treat breast disease includ- ing cancer and benign cysts, tumors, and growths
  • • Procedures to change the appearance of a breast, including restoring the absence of a breast, increase or decrease in breast size, or revision of breast shape and position 
Recently, however, a third category of breast surgery has emerged: surgery to prevent breast disease. While prophylactic bilateral mastectomy has been elected as early as the 1980s to significantly reduce a woman’s chances for developing breast cancer, it only recently has become an accepted practice in the prevention of breast disease in women who are carriers of the breast cancer genes BRCA1 and BRCA2. Studies show that there is a 90% reduction in the incidence of breast can- cer among these women. However, recent studies have demonstrated that even women who are not carriers of the breast cancer gene can, in fact, reduce their chances of developing breast cancer. 

In a study published in the June 2004 issue of Plastic and Reconstructive Surgery, women with overly large breasts and without the pres- ence of certain genetic factors relative to breast cancer who underwent breast reduction were found to have a reported 50% to 70% reduction in the incidence of breast cancer.

Beyond the categories of breast surgery to either treat disease or change appearance, breast surgery can also be defined by medical specialty:
• General breast surgery: to diagnose and treat breast disease through the removal of the entire breast, or only of diseased tissue, tumors, or cysts
• Plastic surgery of the breast: any surgical procedure that changes or restores the appearance of the breast, including those procedures to treat and pre- vent breast disease that result in the change of breast appearance

100 questions and answers about breast surgery / Joseph J. Disa, Marie Czenko Kuechel.— 1st ed. p. cm.
ISBN 0-7637-3041-6 (pbk.)
1. Breast—Surgery—Popular works. I. Title: One hundred questions and answers about breast
surgery. II. Kuechel, Marie Czenko. III. Title. RD539.8.D57 2006

Tuesday, January 3, 2012

New Year Quotes and Sayings

Well, a new year is starting, another chance to workout and reach our dreams.
there's a website "123newyear" and they made a post that we want to share here:

New year is an wonderful occasion, when we welcome something new in our lives and at the same time, forget about all the bad memories, which the passing year gave us. Happy new year quotes is one of those means, with which you can celebrate the new year with elan. All these beautiful new year quotes are written by famous personalities.

If you want to make your own new year quotations ,you can take inspiration from the below mentioned new year sayings.

Do something quotable this new year. And, inspire others to do such deeds in the years to come. And make it a point to consider your everyday as first day of the year. And welcome the daily sun as you welcomed it on the first day of the year. 

Tell your partner that you would abide with him/her no matter in what condition life puts you in. Live life king size and do behave like a king, as a king thinks for his people and puts their needs first before thinking about his own. Become proactive and do things which makes you happy. Cheers. Happy New Year.

Do something quotable this new year. And, inspire others to do such deeds in the years to come. And make it a point to consider your everyday as first day of the year. And welcome the daily sun as you welcomed it on the first day of the year.

Tell your partner that youd abide with him/her no matter in what condition life puts you in. Live life king size and do behave like a king, as a king thinks for his people and puts their needs first before thinking about his own. 

Become proactive and do things which makes you happy. There is a famous quote from a celebrated personality Tom Bergeron, “May all of your resolutions (except the ridiculous ones borne of misplaced guilt) be realized. That should take care of most of them…” cheers to the spirit of this quote and a new life. Cheers. Happy New Year. 

 We are going to post more interesting articles.
Keep Reading us!