LED Street Lighting: Benefits Of An Extended Life

LED Street Lighting: Benefits Of An Extended Life

Categories: Company News, Energy, Municipal Government

Within the last decade, LED technology has significantly improved allowing production costs to be reduced while the efficiency and performance characteristics continue to increase exponentially. Due to these continually progressing improvements, LED technology has become the lighting option of choice for roadway and exterior area lighting. Another major advancement in LED technology is the extensive lifespan of modern systems.

LED fixtures’ useful life spans differ from traditional street lighting fixtures in that traditionally HID lamp and ballasts are used. The lumen output of HID decreases rapidly over time until they fail or “Burn-out”. In contrast, LED systems lumen output diminishes gradually over time, and are often defined with an L70 rating of >100,000 hours. These ratings define the usable light levels of a fixture as a percentage of its original output. For instance, a lamp with an L70 rating of >100,000 hours will be producing 70% of the light out output that it was producing new once in service for 100,000 hours.  This high rating allows for more accurate budgeting for when the fixtures will need to be replaced in order to maintain desired light levels. The useful lifespan for HID lamps is on average 5 years with ballasts needing to be replaced approximately every 10 years. Most modern LED fixtures available today have useful lifespans exceeding 25+ years for normal dusk-to-dawn operation. The following chart illustrates the lumen maintenance curves for the various technologies.

Source: Pacific Northwest National Laboratory for the Solid-State Lighting Program of the U.S. Department of Energy

The many advancements of LED technology over the last decade has resulted in a viable energy efficient replacement option. Well-designed LED luminaires have high fixture efficacies, optimized color rendering, directional optics, and extensive useful lifespans. These factors allow for the replacement of existing fixtures with LED systems that utilize substantially lower wattages, all while meeting or exceeding the same light levels.

Save 60-75% on Street Lighting Guaranteed With Wendel Energy Services

Installing lower wattage and longer lasting LED street lights reduces energy and maintenance costs by 60-75%. Wendel’s professional, in-house staff will perform a no cost/no pressure Preliminary Assessment of the potential for savings with your community’s street lighting. These same professionals can then design and implement a street lighting upgrade with 100% cost transparency.

LED Street Lighting: Why Blue May Not Be For You

Categories: Company News, Energy, Municipal Government

Correlated Color Temperature (CCT) is the description of a light’s color in terms of its warmth or coolness. Represented by Kelvin, a CCT of below 3,000K will have a warm white appearance similar to that of an incandescent. As this value increases the light will become brighter and cooler. There is an ongoing discussion in the street lighting community concerning what an appropriate CCT is for street lighting, as LED’s with various options for CCT and Color Rendering Indexes (CRI) have come into the picture. There are many factors that come into play in this discussion and affect what CCT is chosen for a particular street lighting project.

Safety

The international Dark-Sky Association (IDA), an organization focused on the control of light pollution, published a paper outlining the potential hazards of blue-rich white light sources. These blue-rich lights represent LEDs with high CCTs. The study found that increased blue light emissions increased the likelihood of glare and interference of the ability of the eye to adapt to low light levels. These emissions have also been known to interfere with the human endocrine system, leading to a reduction in the production of melatonin, a hormone shown to suppress breast cancer growth and development. IDA sought to avoid these effects by creating an FSA (Fixture Seal of Approval) requiring lighting with a CCT of 3,000K or lower.

Poor lighting caused by low CCT can also make it difficult for motorists to see hazards or objects clearly at night, creating an unsafe driving environment. Utilizing LED luminaires with higher color temperatures, such as 4000K, improves safety conditions when properly designed for the application. The higher or whiter the color temperature, the greater the perception of brightness is to the human eye. This allows for an increased ability to perceive colors, definition, and movement of other drivers, pedestrians, and objects all in a comparatively low light setting. It has also been shown that white light doubles a driver’s peripheral vision and reduces their braking times by 25% when compared to high pressure sodium lights (HPS) which have a low CCT. Locations that could benefit from this approach include areas where security is a concern, or high pedestrian conflict areas, such as intersections and downtown districts with a lot of nightlife.

Circadian Rhythm

Circadian rhythm is the internal clock that controls your sleep/wake cycle. It’s what causes you to feel tired at night and alert during the day. Outside factors such as light and darkness impact this cycle, which is why we get more tired as it gets darker and vice versa. When LED’s emerged as a viable and efficient light source, concerns arose that the white lights would cause circadian and sleep disturbances. Philips lighting, a global leader in LED lighting solutions, have stated that if properly designed and applied, there should be no impact on sleep behavior. This proper application and design involves choosing the right optics and light intensity for the area of application, specifically CCT.

Cost

In the first few years of LED outdoor lighting use, lights with higher CCTs were more available, efficient, and cheaper than those of lower CCTs. Efficiency losses occurred when creating warmer CCTs and thus production of these warmer lights was low. With advances in LED technology, warmer CCTs could be made without losing as much efficiency. Even with these advances, however, a higher-CCT LED is more efficacious than that of a lower CCT, keeping all other properties equal. This efficiency translates to lower utility costs and greater environmental benefits.

Appearance

Choosing the right CCT can affect not only the safety of an area, but the aesthetic appearance as well. Street lights with too low of a CCT will appear orange in color and cause a scene to look dreary or dark. Studies have consistently shown that this orange light makes streets look darker than a white-lit street, even with identical levels of luminance. Below is the difference between a street with lights of low CCT’s compared to the same street after having the lights replaced with LED’s with higher CCT’s.

City of Poughkeepsie, NY – AFTER
City of Poughkeepsie, NY – BEFORE

 

 

 

 

 

 

 

Save 60-75% on Street Lighting Guaranteed With Wendel Energy Services
Installing lower wattage and longer lasting LED street lights reduces energy and maintenance costs by 60-75%. Wendel’s professional, in-house staff will perform a no cost/no pressure Preliminary Assessment of the potential for savings with your community’s street lighting. These same professionals can then design and implement a street lighting upgrade with 100% cost transparency.

Establishing the Baseline

Categories: Company News, Energy, Sustainability

How utility bill data creates a reliable foundation for accurate energy savings.

Energy efficiency projects are filled with data; facility operations, occupant behavior, equipment specifications, and utility billing data. Utility billing data forms the baseline for any energy efficiency project. The utility analysis serves as a reliable baseline throughout the project lifecycle. There are four primary uses of utility billing data: utility analysis, benchmarking, utility disaggregation, and measurement and verification (M&V). Each will be discussed in the following paragraphs.

Before an in-field energy audit can be conducted, utility bills are collected and analyzed to establish the base condition for each facility included in the project. Bills are typically collected from at least the electric utility and natural gas utility. If other fossil fuels are utilized, such as propane or fuel oil, those bills would be included in the analysis. Depending on the energy procurement laws in the state where the project is located, there may be additional bills from third-party energy commodity suppliers. Ultimately, the billing data is entered and analyzed to determine the overall energy consumption and the effective unit cost of each utility for use in energy savings analyses.

 

 

 

 

 

 

 

 

The values obtained from the utility analysis are then compared against comparable buildings from the Commercial Building Energy Consumption Survey (CBECS), in an exercise known as benchmarking. The annual consumption for each utility is converted to a common unit (typically kBtu) and normalized by the building square footage to obtain a value known as the energy use intensity (EUI). This value sets all buildings within a particular use type on a level platform for easy comparison. A higher EUI value signifies a less efficient building, having more energy consumption per square foot. High EUI buildings are typically good candidates for a deep energy retrofit project. Even buildings with average or lower EUI values may show higher EUI values for a particular fuel, which may signal opportunities are available to address building systems which utilize that fuel. Costs may also be analyzed on a per square foot basis and compared against national or regional data. This can help target the most costly fuels with applicable energy conservation measures (ECM). Lastly, the profile of energy consumption for each category of building system (lighting, HVAC, plug loads, water heating, etc.) can be developed using the national or regional CBECS data for comparable buildings.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

During the audit and design phases, utility data is used to continually evaluate the reasonableness of energy savings calculations. Past experience and experimental data provide typical energy savings values for particular ECMs. If calculated savings fall outside of expected values, further investigation and changes to the calculations can be made to modify the analysis for increased accuracy. The calculations are then used to separate utility consumption into energy consumption by building system, known as a utility disaggregation. The utility disaggregation is similar to the energy consumption by category profile developed during benchmarking, but instead uses building specific data and calculations rather than CBECS data.

 

 

 

 

 

 

 

 

 

 

 

 

At the end of the project, depending on the contract, measurement and verification may be required. If M&V is required, utility billing data is collected for the 12-month period from project close-out through the following year. Depending on the M&V method agreed upon, energy savings can be evaluated based on utility bill savings. In other instances, the utility analysis may determine the effective unit cost to be used in calculating the achieved cost savings from measured reductions in energy consumption.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Considering the many uses of utility data throughout the project lifecycle, getting the data right is paramount. Utility data is the foundational element to any energy project, critical for providing accurate baselines, benchmarks, and unit costs. This foundation, much like that of a building, must be solid to ensure a good project.

 

Written by:  Justin M. Imiola, ISSP-SA | Energy Engineer

Wendel Project Managers Obtain PMP Certifications

Categories: Uncategorized

Wendel is pleased to announce that members of their project management team have obtained their Project Management Professional (PMP) certifications from the Project Management Institute. The PMP is the most widely industry-recognized certification for project managers worldwide. Wendel’s decision to elevate its team to this next level was based on their ongoing commitment to quality and career development initiative.

“Our push to have more certified Project Management Professionals is twofold. First, we think it will make our folks better project managers. This will benefit everyone including the client and the firm. Second, we want it to be obvious to our clients the priority we place on doing project management right!  We are not only technical and subject matter experts but also experts in project delivery!” – Stewart Haney, CEO

Recent PMP certification recipients from Wendel include Christopher P. George PE, PMP Lindsay Brownschidle RA, PMP, Susan Sherwood, PMP Amanda Williams, PMP and Michael Galley, PMP. They look forward to sharing their expertise with their clients.