LED Infusion Paves Home’s Greener Upgrade


Credit: Don Campbell

How do you save $19,500 a year in electricity costs? Upgrade a big system by downgrading its power consumption.

Jan. 21, 2010 — by .(JavaScript must be enabled to view this email address)

Think about it: You spend a fortune building a massive slope-side vacation home in Utah, complete with a home control system, lighting control system and a snow melt system—only to have your electrical contractor come back two years later to rig about $60,000 worth of energy-saving improvements.

“Everything about the project was big,” says Mark McGuinness of Chesley Electric in Park City, Utah, of this 16,500-square-foot home that recently won lighting company Lutron’s Excellence Award for Best Green Project. “The service at 1,200 amps [most homes have 100- or 200-amp service] was the biggest we had done at the time. A nine-panel Lutron system with 78 SeeTouch keypads was also the biggest we had ever done.”

Unfortunately, all that “big” resulted in big energy bills—about $5,000 a month. The homeowner surely wanted to save money, but McGuinness says he’s also well known in the community and wanted to be environmentally conscious. (Click here to view a slideshow of more photos.)

What to do? Chesley focused on two areas: lighting and the snow melt system, the latter of which was ramping up the utility bills during the winter months. “And the Lutron system gave us all the equipment we needed to dramatically reduce his power consumption,” McGuinness says. The result: a savings of 76,000 kilowatts of power, or about $19,500 a year—and that’s just during the five winter months when the house is occupied.

LED Retrofit
The lighting system fix was relatively straightforward. Chesley replaced all the system’s halogen lighting, inside and out, with LEDs (light emitting diodes) from LED Power. And while that “upgraded” the system, it drastically “downgraded” the amount of energy used in the house.

A total of 26,348 watts reduction, or about 90 percent energy savings, was achieved by changing 300 MR16-type lamps, 186 recessed outdoor PAR (parabolic aluminized reflector) lamps, and 1,000 decorative festoon bulbs to LEDs (See “Lighting Before and After” sidebar).

But just adding LED bulbs in a dimmable lighting control system is not an easy trick. Many LEDs are made differently, and the lighting control system has to be able to work with the lamp’s electronic driver. LEDs are, after all, pieces of solid-state electronics. That often means that some can be dimmed by a system, but others cannot. In this case, the Lutron HomeWorks system is able to dim the 300 or so MR16 lights, but not the recessed PAR lamps. So Chesley programmed the lighting control system to shut off the PAR lamps during certain dimmable scenes. For example, in the kitchen, when a SOFT scene button is pressed, the MR16s over the cabinets dim, and the six receding PAR lamps shut off.

Interestingly, Lutron now has a module that recognizes the small loads to dim such lamps, but McGuinness says that was not a part of the system originally installed.

The 65 PAR lamps outside don’t dim, either, but are controlled by a clock to turn on and off automatically.

That’s not all. Chesley integrated into the Lutron System some security motion sensors that had been installed at the corners of the guest rooms and public spaces. Now when the security sensors detect motion, the light in the room stays on. When they don’t, the lights shut off. 

Chesley also created some nice effects with the LEDs. “In the dining room we programmed the lighting over the glass ‘wave’ wall to pulse from the center outward with alternating colors to give the effect that the wall was waving,” McGuinness says.

LED lamps, especially this many of them, don’t come cheap. The cost of this lighting system do-over ran about $60,000—$40,000 of that was spent on just the LEDs—but it resulted in a savings of 51,870 kilowatts of power, or about $1,300 a month.

No More Melting Money
A new snow melt system on the roof wasn’t needed, but some innovative “programming” saves as much as $2,600 during the winter months. “The snow melt system was also the biggest we’d ever done, pulling 400 amps when operating at 100 percent,” says McGuinness. In more familiar terms, McGuinness says that equals 96,000 watts. That, friends, is a lot of juice.

By using Lutron’s wired Maestro switches and an astronomical time clock, Chesley was able to “pulse” each individual zone of the snow melt system during the winter. “Basically all we’re doing is turning the Maestro off for 20 minutes every hour.  By alternating between the 24 zones, we eliminate the possibility of freezing because we don’t have the gutter and eave off at the same time. Because of that the water will always flow.” 

And what to do when the temps dip below minus-10 degrees Fahrenheit? At this temperature the water will freeze in the 20-minute shut-down period, so two exterior thermostats were installed to trigger the systems to turn on. And when it’s 20 degrees outside, which would normally turn on the system, but it hasn’t snowed in two weeks? The system won’t turn on. “By tying into the driveway moisture sensor (installed by the HVAC contractor) we are able to get a signal sent to us when there is moisture present,” McGuinness says. In order for the system to turn on, it has to check the temperature, the moisture and the date. The earliest the system can turn on is Oct. 15.

“The whole first winter was kind of a test, to see if the 20-minute interval was working,” says McGuinness. Fortunately it did, and the homeowner is saving $2,600 a month just in the snowmelt system adjustment—and for an investment of about $4,000.

With a total savings of $3,900 during five winter months, McGuinness figures that the $40,000 spent on the LED lights alone, as well as the $4,000 for the snow melt system programming, will pay for itself in 2.5 years. The total cost will take a little longer, but this downgrade in energy consumption was an upgrade well worth making.

Electrical and Lighting System
Chesley Electric
Park City, Utah

Lutron Series 8 Processors (2)
PNL 8 Panels (14)
HW-RPM-4U-120 (140)
HW-RPM-4R (8)
HWD-8ANS (15)
SeeTouch Keypads (78)

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