Ventilation Louvres

how can i lower the electricity consumption of a 160 unit, mid-rise condominium?

i would like to design the building to be energy efficient (the building is in a tropical climate) besides designing the building to allow natural sunlight and ventilation (passive cooling to save on air-conditioning) i am thinking of using LED for lighting some parts of the building, can you give me comparison of CFLs LEDs and ordinary lights (prices etc.) thanks!

Public Comments

1. Wasn't sure whether you meant comparision of purchase price or power saved so the first site lets you plug in watts used in one bulb vs. watts in another x duration and tells you savings the second is a site that sells different types of lights
2. maybe you ought to paint it white, so it warms less, and requires less AC. maybe you want to have a 2nd water system, to use solar heated water to feed to the hot water heaters. maybe you want to design awnings over the windows, so that during the hottest part of the day, sunlight doesn't shine in. maybe you want to specify window glass that blocks UV radiation and keep at least part of the heat out. i'd think that right now, light bulbs would be a minor consideration. i mean, you can change that after the building is done. maybe something better, or cheaper, will come along.
3. raise the energy rates!
4. One of the big issues with CFLs are the hazardous waste disposal requirements. Right now they remain popular because of the electrial savings. But, give it a few more years and they will become a liability. If possible, I would design for LEDs. When I think tropics, I think in terms of needing to mitigate excess solar heat. Certainly double paned windows should be a consideration but, you might want to look into triple paned windows as well. I would think in terms of looking into serious window coverings. The This Old House folks did a project in what I remember as being the Bahamas. There, wood shutters are used to seal out the mid-day sunlight and solar energy. Also, the slant of the slats is used across open windows to dispell interior heat as well as allow evening breezes to flow through. The City of Chicago, IL in the USA is doing some interesting things with roof top and street side vegetation; they have some data to support this vegetation's effectiveness in keeping their buildings cooler and air conditioning energy savings. The last I heard, they are now working with vegetation up and/or along the sides of buildings to reduce summer heat. Shielding or shading the exterior sides of buildings has been used in many cultures over the years to mitigate temperature extremes. Old plantation houses and mansions in the US south used 10 to 15 wide porches, sleeping porches, and verandas. Many cultures have used walled court yards. There is some evidence to support that even as little as an 18" wide eve mitigates winter chill and summer heat. Often, awnings do more than just protect folks from the rain and snow over a door way. Partially or wholely coverered patios and arbors, either by building materials or vegetation, are used to shield and shade buildings. Surrounding ground surface material can also affect immediate area heat. For example, black top aborbs and retains heat. Unshaded cement reflects heat upon surrounding surfaces with great intensity. Even unshaded swimming pool water can reflect a fair amount of heat. Of course, thick walls provide more insulation which also mitigates both external heat and cold. In hot and humid climates, fans are often a less energy intensive alternative to air conditioning. But, if your goal is to be "green" don't forget to design in the capability to seperate garbage from recyclables. Alternative energy gathering such as heated water systems could be part of the plan. But also, consider electrical, in-line water heaters as opposed to the traditional water tank system. Often, in-floor radiant heat and cooling through the use of piped water uses less energy than traditional heating systems. The choice of paint color and finishes can also make one feel warmer or cooler which can lead to less energy use despite the temperature. Lastly, you may be able to plumb in some water savings concepts. My bias is that individual water meters as opposed to whole-building or complex-wide water meters help individuals better identify and then motivate changes in water usage.
5. Compact florescent have a better spread than LED lights. LED tends to be very directional and focus's on a smaller area. The developers of this technology are working to make this better. A convex design allows LED to have a better spread. The light does not spill over as much as other products. This can be useful in some instances and it can be a hindrance as well. LED have problems in hotter climates and might prove ineffective in your environment. Consult the manufacturer for info. Off grid landscaping lighting would be a great idea for this project. At this time there are limited choices in LED compared to other technologies. It is a product that is useful in many ways and has a promising future. The CFL are a proven commodity. Much of the concern of the mercury content is over blown. Yes the should be disposed of properly but he amount of mercury is very small. They come in many shapes and sizes. With education and a proper recycling area this is easy to overcome. CFL general are good for residential and any area that take a common edison screw fitting. They are not for larger areas such as parking lots or outside lighting As far as cost the up front cost of LED is high. However in the long run it might be cheaper based energy disposal and longevity. Replacement cost is high and there is a limited selection of product at this time. The upfront cost of CFL is cheaper and has alonger track record of reliabilty compared to LED. Must be diposed of properly to be responsible. Replacement costs are cheap. Other considerations for Energy Effciency besides passive solar Super Insulation Tight envelope ducting in living space solar thermal (hot water) PV and Wind Turbine (If applicable) Limit glazing and proper orentation Well placed overhangs Good Luck