Additional information comparing Skylights and other daylighting technologies to SunPipes®
Energy-Saving Attributes of SunPipes Over Traditional Daylighting Technologies.
Compared to other daylighting technologies, only SunPipes (and certain other brands of daylight pipes with a positive, airtight seal at the ceiling dome) actually save energy. Consider these points:
1) Virtually no summer heat gain.
In the summer, traditional daylighting technologies let in a lot of the suns' heat, causing an increase in air-conditioning energy consumption that far outweighs any electric lighting energy savings.
2) Virtually no winter heat-loss.
In the winter, warmed air rises, gets cooled by horizontal or vertical glazing, then sinks to be reheated. Then, after it's reheated, it rises, gets cooled, and sinks to be reheated. Then it rises, gets cooled and sinks to be reheated (repetition intended). Again, traditional daylighting technologies waste far more heating energy than they save in electric lighting energy.
3) Minimal invasion of the thermal envelope.
Traditional daylighting technologies require the removal of 10 times more roof (or wall) insulation than a SunPipe®. Whether it's a wall of vertical windows that allows daylight to reflect off a white wall for indirect lighting (a clearstory), or skylights that just let the sun shine in through the roof, the insulation sacrifice is tremendous.
A common residential skylight measures 30" X 60" which is over 12 square feet in area. A SunPipe-13 is less than 1 sq. ft. in area, yet it brightens up a greater area of the room than does the skylight. In this case, and as a general rule, installation of a skylight requires the removal of 11 times as much roof insulation as the installation of a SunPipe-13.
Commercial / Industrial Example:
A 5 x 6 skylight (30 sq. ft.) is common in industrial buildings and provides intense illumination in only a restricted area of the interior room based on the trajectory of sunlight through the skylight. One SunPipe-21 (2.4 sq. ft.) will illuminate a larger area more uniformly than the skylight and preserve 27.6 sq. ft. of roof insulation in the process. The skylight requires the removal of 11.5 times as much roof insulation as the SunPipe.
While We're At It, Let's Save Those
SunPipe® also reduces relamping frequency. Lamps that required replacement after 1 or 2 years will now last 4 to 5 years. This prolonging of lamp life reduces landfill burdens.
Reduce Disposal of Heavy Metals and Hazardous
Along with lower relamping frequency comes a reduction in the disposal of heavy metals and hazardous waste products (ie. mercury and phosphorous), materials found in fluorescent and certain HID lamps.
SunPipe® customers, whether residential or industrial, reduce electric-lighting energy requirements with every SunPipe® installed.
Electric lighting savings examples:
1) At the low end of the energy-saving scale is a retired residential couple who spend a considerable amount of time at home with a 13 inch diameter SunPipe-13 in a kitchen (where 60% of SunPipe-13's go). This SunPipe® typically replaces the burning of 200 to 500 watts of electric lights for 3 to 7 hours per day. For this example we'll assume a 300 watt savings for 5 Hrs. per day, 5 days per week.
The Result: One SunPipe-13 saves 390 kWh per year.
2) At the upper end of the scale is an industrial customer who installs 100 of our 21 inch diameter SunPipe-21's. Conservatively speaking, each of these SunPipes® replace the burning of a 400 watt HID lamp for 5 hours per day, 5 days per week.
The Result: 100 SunPipe-21's save 52,000 kWh per year = 5.2 megawatts.
Power Plant Emissions Savings:
The above electric-lighting energy savings results in significant emissions reductions from power plants.
1) Emissions reduction based on the savings of 390 kWh of electricity:
Carbon Dioxide (Greenhouse Gas) - 702 Lbs.
Nitrogen Dioxide (Smog) - 1.95 Lbs.
Sulfur Dioxide (Acid Rain) - 2.34 Lbs
High-Level Nuclear Waste (Serious trouble for our great grand kids) - 0.468 oz.
2) Emissions reduction based on the savings of 52,000 kWh of electricity:
Carbon Dioxide (Greenhouse Gas) - 93,600 Lbs. (46.8 tons)
Nitrogen Dioxide (Smog) - 260 Lbs.
Sulfur Dioxide (Acid Rain) - 312 Lbs.
High-Level Nuclear Waste - 62.4 oz.
HVAC Energy Savings:
When using SunPipes® in lieu of traditional skylights, HVAC energy savings is many times greater than electric-lighting energy savings... by a factor of 10 or more, simply because AC compressors and blowers consume far more energy than do lights.
Sun Pipe Company's Super-Efficient "Virtual"
The Sun Pipe Company is a "virtual" manufacturer. We reduce consumption of all types of energy use by using other businesses to manufacture our parts, rather than making them ourselves with our own fossil-fuel-consuming facilities and equipment. From the acrylic domes that cap each end of a SunPipe®, to roof flashings, nuts and bolts, every SunPipe® component is either an off-the-shelf product produced by other companies or is a uniquely specified component produced for us by other companies. We even contract out warehousing and order fulfillment operations.
Really Interesting (and highly technical) Data From The EPAs' Web Site.
"As individuals, we can directly affect the emissions of about
4,800 pounds of carbon equivalent, or nearly 32% of the total
emissions per person, by the choices we make in three areas of our
life. These areas are; 1) the electricity we use in our homes, 2) the
waste we produce, and 3) personal transportation. The other 68% of
emissions are affected more by the types of industries in the U.S.,
the types of offices we use, how our food is grown, and other
Total national emissions per year:
Carbon Dioxide (Greenhouse Gas) - 6,746 Tg.*
Carbon Dioxide (from 1999 electric utilities) - 1953.4 Tg.*
Nitrogen Dioxide (Smog) - 7.4 Tg*
Sulfur Dioxide (Acid Rain) - 20.5 Tg.*
*NOTE: 1 Tg (teragram) = 1 million metric tons
"All gases... are presented in units of teragrams of carbon dioxide equivalents (Tg CO2 Eq.) The relationship between gigagrams (Gg) of a gas and Tg CO2 Eq. can be expressed as follows:
TgCO2 Eq = (Gg of gas)x(GWP)x(Tg/1,000 Gg)"
"The global carbon cycle is made up of large carbon flows and reservoirs. Hundreds of billions of tons of carbon in the form of CO2 are absorbed by oceans and living biomass (sinks) and are emitted to the atmosphere annually through natural processes (sources). When in equilibrium, carbon fluxes among these various reservoirs are roughly balanced."
"Since the Industrial Revolution, this equilibrium of atmospheric carbon has been altered. Atmospheric concentrations of CO2 have risen about 28 percent (IPCC 1996), principally because of fossil fuel combustion, which accounted for almost 98 percent of total U.S. CO2 emissions in 1998. Changes in land-use and forestry practices can also emit CO2 (e.g., through conversion of forest land to agricultural or urban use) or can act as a sink for CO2 (e.g., through net additions to forest biomass)."
Carbon Dioxide Emissions and "Electric Utilities.
The United States relies on electricity to meet a significant portion of its energy demands, especially for lighting, electric motors, heating, and air conditioning. Electric utilities are responsible for consuming 27 percent of U.S. energy from fossil fuels and emitted 36 percent of the CO2 from fossil fuel consumption in 1999. The type of fuel combusted by utilities has a significant effect on their emissions. For example, some electricity is generated with low CO2 emitting energy technologies, particularly non-fossil options such as nuclear, hydroelectric, or geothermal energy. However, electric utilities rely on coal for over half of their total energy requirements and accounted for 85 percent of all coal consumed in the United States in 1999. Consequently, changes in electricity demand have a significant impact on coal consumption and associated CO2 emissions."
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Skylights vs SunPipes
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