1. CenterPoint Energy Street Light Luminaire Replacement
City of Houston LED Street Light Conversion Project
Introduction & Background
May 8, 2015

2. CenterPoint Energy LED Street Light Replacement
The purpose of this presentation is to:
Introduce LED street lighting technology
Highlight CNP’s LED pilot program and evaluation process
Provide information on the conversion project with City of Houston
Quick explanation of purpose

3. Street Lighting Background
Approximately 410,000 street lights in system
Types of Street Lighting
Overhead Cobra Street Lights
Underground Cobra Street Lights
Decorative Street Lights

4. Lamp Types High Pressure Sodium Metal Halide Mercury Vapor
Amber/Orange in Color
Standard Installation
Economical – 8 year life
Metal Halide
White/Blue in Color
Not Economical – 2-3 year life
More Expensive
Mercury Vapor
Restricted Availability
1,000 left in system
LED – Light Emitting Diode
Highly Efficient – 8-10 Years
Examine the comparison a little closer

5. Why the interest in LEDs?
The U.S Department of Energy estimates that widespread adoption of LED lighting by 2025 will:
Reduce electricity demands from lighting by 62 percent.
Eliminate 258 million metric tons of carbon emissions.
Reduce the amount of materials being put into landfills.
Avoid the building of 133 new power plants.
Save the US over $280 billion.
For one, the DOE states that the widespread adoption of LEDs, not just in the area of street lighting, will reduce energy demand, carbon emissions, and landfill waste while reducing the need to build new power plants. That total estimated savings is near $300 billion dollars. In addition, the fact that LEDs are a “green” commodity has caught the eye of the public and has caused a huge demand for this product.

6. What is LED?
Light-Emitting Diode: a semiconductor device that emits visible light when an electric current passes through it

7. Typical Lighting-class LED Package
Lens, RI ~1.4
Substrate
Wire Bond
Phosphor
LED chip
The LED Package provides:
Protection for the LED chip from the outside environment
Conductive path to carry generated heat away from the LED chip
Reliability
Lens & encapsulant systems should not discolor under UV and exposure to high amounts of luminous flux
Example of an LED pkg. Point out the LED chip, substrate, wire and lens. Point out the difference between HID lamps
Show sample LED chip

8. HID Lamp vs. LED Technology
Technological Differences:
Directionality of generated light
Omni-directional (HID)
Directional (LED)
Means of evacuating generated heat
Convection (HID)
Conduction (LED)
Light Source
Single (HID)
Multiple (LED)
HID lamps:
Reflector
(light)
(heat)
LEDs:
90°-140° viewing angle
(light)
(heat)
The traditional HID lamps radiate light from a single source in many different directions and must be controlled by the use of reflectors and refractors. While traditional lamps have been rather economical, they have not been very efficient in their use of energy and light distribution. They produce a good quality of light, but, they provide a challenge when it comes directing the light to specific locations. They have contributed a lot to the up-light or light-trespass in our communities. This has caused many municipalities to enact Dark Sky compliant laws and standards to better control light going back into the atmosphere.
LED light technology, on the other hand, provides a highly directional light source that can be digitally manufactured in a laboratory to place light in a very specific pattern in a very specific location. By using varied numbers of LED’s (anywhere from 20 – 30 per fixture to or more per fixture, manufacturers are able place light more distinctly in desired areas on roadways and sidewalks and eliminate wasted or unwanted light.

9. HID Light Pattern vs. LED Light Pattern - 150W HPS
Comparison of 150W FCO HPS vs 90W LED Roadstar Type 2

10. HID Light Pattern vs. LED Light Pattern - 150W HPS
Comparison of 150W FCO HPS vs 90W LED Roadstar Type 2

11. HID Light Pattern vs. LED Light Pattern
Comparison of 250W Drop Lens HPS vs 180W LED Roadstar Type 2

12. HID Light Pattern vs. LED Light Pattern
Comparison of 250W Drop Lens HPS vs 180W LED Roadstar Type 2

13. Traditional Street Lights vs. LED Luminaires

14. Traditional Street Lights vs. LED Luminaires
Operate – A Culture of Safety – High Quality White Light

15. Traditional Street Lights vs. LED Luminaires
Serve – Customer Focus – Societal Benefits such as Dark Sky Initiative
Los Angeles Skyline – 2008
Los Angeles Skyline – 2012

16. LED: Advantages and Disadvantages
CenterPoint Energy has been conducting pilot testing of the technology for the previous six years
ADVANTAGES
Energy efficient: 80% of the electricity used by an LED is converted to light, compared to just 10% for incandescent bulbs.
Long and predictable life: LEDs last up to 100,000 hours or more; substantially longer than High Pressure Sodium and Metal Halide lamps
Excellent CRI (color rendering index): LEDs can produce a high quality of white light that allows the eye to detect colors more effectively.
Environmentally friendly: LEDs emit very little infrared radiation and contain no mercury.
Directional lighting: LEDs focus light in a particular direction, making them useful for spotlight and other applications.
Quick turn on and off: LEDs come on with full brightness instantly. Unlike mercury vapor, metal halide and sodium vapor lamps (commonly used in street lighting), LEDs do not have a problem restarting immediately (hot ignition) following a brief power failure or inadvertent turn off.
LED luminaires may provide up to approximately 60% kWh energy savings for the end-use customer
DISADVANTAGES
Cost: LEDs are currently more expensive than other conventional HID sources.
Heat: LEDs are very heat sensitive. Correct dissipation of heat is necessary to light output and lifespan of the fixture.
This technology has grown by leaps and bounds over the last few years. Corporations, cities, municipalities, and utility companies recognize the value of energy efficiency, cost savings, and the environmentally friendly nature of LEDs.
Other advantages seen especially by utilities and municipalities are reductions in labor and maintenance to street light systems. LED lasts 2X longer than HPS and 10X longer than MH
The main challenges at this time is controlling thermal management especially in warm climates and dealing with the high initial cost of these new LED fixtures.
We have seen a steady decrease in the cost of luminaires as the technology has developed and production has increased.

17. CenterPoint Energy LED Pilot Study
In May of 2009, CenterPoint Energy was approached by our largest street light user, the city of Houston (approximately 175,000 lights), about exploring LED lighting and its benefits and possibilities.
These lights have been installed at no charge to our customer base in a local subdivision that would promote and allow feedback from the community.
Initial Participation Criteria
Provide 3 LED test fixtures to replace a 100W high pressure sodium fixture
Meet full cut-off requirements and
Type II Distribution
The test location is an existing subdivision in Southeast Houston with no competing tree canopies and the luminaire mounting heights are at 30 feet. The pavement width is 28 and all poles are staggered approximately 180’ apart.

18. CenterPoint Energy Sample Pilot Map
The test location is an existing subdivision with no competing tree canopies and the luminaire mounting heights are at 30 feet. The pavement width is 28 and all poles are staggered approximately 180’ apart.

19. Evaluation Criteria Input Power (Watts)
Input Current (Amps) Actual on-site measurement
Lumen Output
Weight
EPA Rating (Effective Projected Area)
LED'S (Manufacturer and number used, type and size of driver, warranty on LED’s, warranty on driver)
Installation Concerns (As noted by field consultant and service technician during initial installation.)
CRI (Color Rendering Index)
IP66 Rated
Photometric Files Available / LM-70 Data
Color Correlated Temperature (Kelvin)
Cost
Arrestor Protection
Junction Temperature
Production Capacity
External 3 prong photo receptacle

20. Field Measurements Lighting Calculations Total FC = 14.373
Street number: 4
Street name:
Linden Gate Dr.
Company:
Brand X
15 ft behind pole
Pole / number
Street readings
0.478 O
0.499
0.807
0.694
0.671
0.408
0.586
0.626
0.421
0.321
0.340
0.371
0.344
0.782
0.686
0.812
0.472 O
0.459
0.427
0.382
0.441
0.323
0.373
0.318
0.286
0.496 O
0.512
0.760
0.630
0.741
Lighting Calculations
Note: Darkest area represents strongest concentration of light.
Total FC =
14.373
(28 readings on pavement between 3 fixtures)
Average FC =
Minimum FC =
Uniformity =
(Average/minimum)
Notes
1. All measurements in foot candles
2. Measurements taken June 14, 2010 after 9:00 pm CDT. Lunar phase: new moon (beginning June 12).
3. All light locations are approximately 180' apart and the width of the pavement is 28'.
4. Readings are taken at 60' lengths along the street and 9' widths starting under the pole.
5. Temperature readings taken on September 13, 2010 at approximately 9:30pm.
Readings were taken 4' off curb and 32'' above grade: Light # K and # K
# K and Light # K.

21. Street Light Luminaire Replacement in the City of Houston
The COH LED Conversion Project includes replacing approximately 175,000 mercury vapor, high pressure sodium, and metal halide luminaires with LED alternatives
Removal of existing HID luminaire, lamp and Photoelectric Relay (PER)
Installation of equivalent LED luminaire
Installation of “hardened” Photoelectric Relay (PER)
The City of Houston has an initiative to lower greenhouse gas emissions produced by municipal operations by 10 percent by 2016

22. Equivalent LED Luminaires
Percent of CNP Lamps
Alternative For
45 Watt
~75%
100W MV*
100W HPS*
70W HPS
100W MH*
95 Watt
~10%
175W MV
150W HPS
175W MH
115 Watt
~14%
250W HPS
250W MH
180 Watt
~< 1%
400W MV
400W MH
* MV = Mercury Vapor, HPS = High Pressure Sodium, MH = Metal Halide

23. CNP Approved LED Street Lights
45W, 4800 lumen LED Luminaire
Allowable Range:
45 – 56W
4400 – 5400 lumens
Vendor A
95W, 7900 lumen LED Luminaire
85 – 105W
7110 – 8690 lumens
Vendor B
115W, lumen LED Luminaire
102 – 125W
9850 – lumens
Vendor C
**All approved fixtures are required to have a minimum 10 year warranty
Slide illustrating how we awarded one vendor per wattage category. Made it easier to track the deployment and any warranty issues

24. Street Light Luminaire Replacement in the City of Houston
CenterPoint Energy is replacing approximately 175,000 mercury vapor, high pressure sodium, and metal halide luminaires with LED alternatives
The anticipated time frame for completion of the project is within five years
*Time schedule is contingent upon workforce availability and vendor production constraints
The anticipated number of LED conversions per year
Year 1
Year 2
Year 3
Year 4
Year 5
20%
25%
15%
Year 1
Year 2
Year 3
Year 4
Year 5
35,000
43,750
26,250

25. 5 Year Deployment Map
We deployed the conversions on a work order based system using Lamberts or a geographic grid

26. LED Tariff Rates
List of our new tariff rate effective 12/30/2015

27. LED Tariff Rate Comparison
Lets take a closer look at the HPS equivilents

28. LED Tariff Rate Comparison
Illustration of the same tariff rate for equivalent LED light types, and the difference in estimated Monthly KWH.

29. LED Tariff Added the following paragraphs to the tariff:
Its a lot to read!!!
The first paragraph covers the terms and conditions of the conversion, and acknowledges there is not an LED equivalent for all existing light types.
The 2nd paragraph addresses the fact that no to LED fixtures are the same. It states LED’s can differ in:
physical appearance
lumen output levels
monthly KWH
The 3rd and 4th paragraph addresses the initial lumen, watt and KWH levels shown in the previous table are target values and are not based on any specific manufacturer.

30. City of Houston Conversion Project Timeline
August 2014 – New LED Street Light tariff rate submitted for PUCT approval
November 2014 – PUCT approves new LED Street Light tariff
December 30, 2014 – New LED Street Light rates are effective
January 1, 2015 – Initiated new LED ESI# creation
January 5, Began deployment of 45W cobra LED street lights
February 11, 2015 – CNP Material Standards Dept. approves 95W and 115W manufacturers
March 16, 2015 – Street Light Outage maintenance crews began converting lights on regular maintenance

31. Current Workforce & Deployment Progress
6 deployment crews
Deployment crew consists of one utility head lineman
On average each crew completes 15 – 20 conversions/day
Issued a total of 12,636 street lights for conversion to date
10,300 – 45W LED fixtures
1,117 – 95W fixtures
1,219 – 115W fixtures
Converted 6,490 street lights to 45W LED
24 Street Light Outage maintenance crews
Converted approximately 900 street lights as of April 15, 2015

32. Street Light Luminaire Replacement in the City of Houston
CenterPoint will continue to work toward identifying LED replacement luminaires for the approximate 8,000 City of Houston street lights not covered by the new LED Tariff rates
Estimated kWh savings to the City of Houston: Over 70 million kWh annually
City of Houston projects $28 million in savings over 10 years
No upfront cost to the City of Houston
Initially customers will continue to pay the same monthly CNP tariff rate as current technology; however LED rates will change in the future.
Once the conversion is completed, the City will use an estimated 70 million fewer kilowatt hours annually. Enough to power about 5,400 single family homes
The City projects it will save $28 million in electricity cost over 10 years. **(According to Houston Chronicle article 6/2/2014)
No upfront cost to the customer. Officials with the City and CNP project the long term-drop in maintenance costs will offset the upfront cost of installation.
Rates will change in the future, due to the difference in cost of LED vs HID fixtures. The cost of LED street lights is quickly dropping as technology advances.

33. Coordinating deployment with Public Works Capital Improvement Projects
Challenges
Equipment Failures
8 Luminaires
5 Receptacle failures
3 Driver failures
3 Photocells
All approved street lights and photo controls have a minimum 10 year warranty
Coordinating deployment with Public Works Capital Improvement Projects

34. LED Conversion Program Expansion
Currently the 100W, 150W, 250W, & 400W high pressure sodium are the CNP standard street lights
Municipalities and Home Owner Associations requesting LED street lights will be required to enter into an agreement. Some of the terms & conditions included are:
Deployment Schedule for Conversions
The deployment schedule will be based on the number of lights and current workload
All new street light installations, including the 6% allotment, will be LED technology
Agreement to the recently accepted LED tariff rates, and the potential of increased LED tariff rates in the future
We have expanded the program. We will provide the same offer to all customers

35. Financial Impact of LED Street Light Conversion
LED fixtures average 1 ½ to 3 times the cost of standard HPS fixtures
LED luminaire costs have decreased significantly over time and are expected to continue to decline
Additional capital labor required to replace existing lights
Undepreciated HPS fixtures remain in the streetlight asset base
Energy consumption will decrease by as much as 50% (Retail Provider)
Monthly fixture charge paid to CNP will likely increase substantially
CNP plans to recover LED conversion costs through DCRF annual filing
Increased life of the LED luminaire, coupled with the “hardened” PER is expected to reduce street light outages

36. Conduct a comprehensive evaluation of each LED luminaire
Summary
Conduct a comprehensive evaluation of each LED luminaire
Evaluate photometric files and perform field evaluations
Growing demand for municipalities to decrease their carbon footprint
Great opportunity to partner with customers on a green initiatives
LED street lighting is an emerging technology
The many benefits of LED street lighting should be weighed against the cost of a conversion and potential maintenance savings

37. Questions?