1/4/2010 10:00 AM
In the last
, we discussed several types of studio lighting, including incandescent, halogen and LED. If you missed that resource, read it before continuing this series.
We’ll begin this part's discussion by looking at a lamp technology that everyone loves to hate: the compact fluorescent lamp (CFL).
The development of CFLs opened up a whole new market for fluorescent sources. These new lamps permit design of much smaller luminaries, allowing them to compete with incandescent and mercury vapor in a wide variety of lighting fixtures. If your facility isn’t already using CFLs in virtually all noncolor-temperature-critical locations, consider starting the conversion now. Most luminaries — including ceiling cans, desk lamps, outside fixtures and exit lighting — will accommodate CFLs.
The efficacy of CFLs is 60 lumens/watt, making them highly efficient. They have a color rendering index rating of 1B. These lamps have a lamp life ranging from 7,000 to 10,000hr, which makes them among the longest lived of lamps.
Now, the key complaint about CFLs is color temperature. CFLs can provide a range of correlated color temperatures, varying from 2700K (like an incandescent lamp) to 6000K, which is bluer than the sun. Unfortunately, they are seldom properly labeled. Manufacturers typically use marketing names like natural white or soft white instead of the actual correlated color temperature. A few manufacturers do print the Kelvin temperature on the box or the base of the lamp in small numbers such as 3000K, but there is no consistency.
The good news is that proposed Energy Star requirements for CFLs will require CFLs to have the correlated color temperature printed on the packaging. Consumers will (once they are educated) be able to buy CFL lamps whose color temperature is a closer match to the old favorite tungsten lamp.
A significant downside of CFLs is that they remain expensive, costing from 50 percent to 100 percent more than incandescent. Also, they contain 5mg of mercury, so disposal should be controlled. See the sidebar from Part 1.
Even if you don’t believe in this technology, the old standby 100W bulb is about to become a dinosaur. Standard incandescent lamps of this type will no longer be permitted to be sold after Jan. 1, 2012. The remaining incandescent lamps smaller than 100W will be prohibited from sale on Jan. 1, 2014. Read "Phaseout of incandescent lamps" below for more information on bulb types and dates of phaseout.
Adopt now or adopt later.
To reduce lighting costs, first start with your studio lighting. Figure 1 to the left illustrates several important comparison parameters between a studio lighting package of either incandescent or fluorescent lights. For this comparison, they produce equivalent illumination. The figure provides a comparison of both power consumption and light output for three types of lamp technology: incandescent, fluorescent and hot restrike discharge (CST) lamps. The two key points to recognize are light output and heat produced per technology.
Total power consumed by the tungsten lighting is 22.5kW requiring 6161 BTU of cooling. The fluorescent lighting equivalent requires only 3.6kW of power and generates only 755 BTU of heat. Energy consumption is reduced by a factor of 6.25, and heat dissipation is reduced by a factor of 8.16.
You can compute the equivalent monthly power bill savings based on the local kilowatt cost.
After the studio lighting is up to date, calculate the savings from relamping the rest of the station. For an example of the benefits, see the results station WXXI-TV enjoyed below.
As most engineers realize, budgets are never going to grow, so learn to make do with what you’ve got. Begin now to find ways to reduce your station’s electrical power consumption. Both state and federal regulations will soon become more stringent, and power will cost more. Your only response will be to use less power.
Phaseout of incandescent lamps
The Energy Independence and Security Act of 2007 (the “Energy Bill”), signed by the president on Dec. 18, 2007, requires all light bulbs use 30 percent less energy than today’s incandescent bulbs by 2012 to 2014. The phaseout will start with 100W bulbs in January 2012 and end with 40W bulbs in January 2014. By 2020, a Tier 2 would become effective, which requires all bulbs to be at least 70 percent more efficient (effectively equal to today’s CFLs).
It’s not entirely correct to say "CFLs will be required" or “incandescents will be phased out” because the standards set by the bill are technology neutral, and by 2012, a next generation of incandescent bulbs could satisfy the 30 percent increased efficiency. There are also other lighting technologies, such as halogen and LEDs that will be able to meet the new requirements and are expected to both increase in performance and drop in cost over the next few years.
Lighting is approximately 20 percent of the average household’s energy bill. NRDC estimates this law could cut our nation’s electric bill by more than $10 billion a year.
There are many types of incandescent bulbs that are exempt from this law:
• any kind of specialty light (ie. bulb in refrigerator)
• reflector bulbs
• three-way bulbs
• shatter resistant
• vibration service
• rough service
• colored bulbs (i.e. "party bulbs")
• bug lights
• plant lights
The law applies to the sale of bulbs, not the use of existing stock of bulbs.
Success story: WXXI broadcasting
WXXI-TV Public Broadcasting Council in Rochester, NY, sought to reduce its operating expenses, partially through new studio lighting.
When Rochester Gas and Electric, which serves WXXI’s 21,000sq-ft complex, offered energy audits performed by experienced energy engineers at no charge to its customers, station VP Susan Rogers took advantage of the opportunity. She had an audit conducted on the station’s two facilities. Station engineers were looking for a way to recoup studio improvements within five years. All of the upgrades they recommended involved lighting improvements.
The station retrofitted more than 650 fluorescent fixtures with T-8 lamps and electronic ballasts throughout the studios and offices. In addition, more than 100 incandescent fixtures were replaced with CFL fixtures.
All of the station's incandescent exit signs were replaced with new LED exit signs. The new fixtures required 70 percent less power than old fixtures. Additionally, these fixtures provide a maintenance savings because they last at least 25 years.
Combined, the two facilities will reduce their energy consumption by 191,294kWh. At today’s rates, this produces an annual cash savings of $20,700. The total payback period will take less than five years.