City Street Lighting Research Articles

Application of Genetic Algorithms to Solve MTSP Problems with Priority (Case Study at the Jakarta Street Lighting Service)

Transportation is one thing that is very important and is the highest cost in the supply chain. One way to reduce these costs is to optimize vehicle routes. The Multiple Traveling Salesman Problem (MTSP) and Capacitated Vehicle Routing Problem (CVRP) are models that have been extensively researched to optimize vehicle routes. In its development based on actual events in the real world, some priorities must be visited first in optimizing vehicle routes. Several studies on MTSP and CVRP models have been conducted with exact solutions and algorithms. In a real case in the Jakarta City Street Lighting Section, the problem of determining the route in three shifts is a crucial problem that must be resolved to increase worker productivity to improve services. Services in MCB (Miniature Circuit Breaker) installation and maintenance activities for general street lights and priority is given to light points that require replacement. Because, in this case, the delivery capacity is not taken into account, the priority of the lights visited is random, and the number of street light points is enormous, in this study, we use the MTSP method with priority and solve by a genetic algorithm assisted by the nearest neighbor algorithm. From the resolution of this problem, it was found that the travel time reduction was 32 % for shift 1, 24 % for shift 2, and 23 % for shift 3. Of course, this time reduction will impact worker productivity so that MCB installation can be done faster for all lights and replace a dead lamp.

Smart City Street Lighting System Quality and Control Issues To Increase Energy Efficiency and Safety

According to standards, the lighting system is one of the key elements to provide safety on city roads, defined by quality parameters. LED technology and movement detection sensor interaction bring about new regulation techniques, creating an energy-efficient smart LED lighting system concept. This paper reveals extensive comparative data analysis of Dialux simulation results before the project implementation phase and in-situ quality parameter measurements for various street profiles and LED luminary power types. After the project implementation phase, more than 1000 measurement points are reached. Further, energy efficiency increase issues in smart lighting systems are described in terms of LED luminary dimming profile analysis and future dynamic control application modes. The first findings clearly show that in most cases light output in simulation results is lower than in real situations; therefore, LED luminary power can be decreased, allowing for higher energy savings in first luminary maintenance years, keeping the same defined ME class or safety level. Let us suppose that the traffic intensity data are obtained from smart system sensors. In that case, the ME class can be dynamically selected during different night times, thus increasing safety and providing extra energy savings using the same system elements, as well as leading to better ROI values.

Recovering the city street lighting fraction from skyglow measurements in a large-scale municipal dimming experiment

Anthropogenic skyglow dominates views of the natural night sky in most urban settings, and the associated emission of artificial light at night (ALAN) into the environment of cities involves a number of known and suspected negative externalities. One approach to lowering consumption of ALAN in cities is dimming or extinguishing publicly owned outdoor lighting during overnight hours; however, there are few reports in the literature about the efficacy of these programs. Here we report the results of one of the largest municipal lighting dimming experiments to date, involving ~ 20,000 roadway luminaires owned and operated by the City of Tucson, Arizona, U.S. We analyzed both single-channel and spatially resolved ground-based measurements of broadband night sky radiance obtained during the tests, determining that the zenith sky brightness during the tests decreased by (−5.4±0.9)% near the city center and (−3.6±0.9)% at an adjacent suburban location on nights when the output of the street lighting system was dimmed from 90% of its full power draw to 30% after local midnight. Modeling these changes with a radiative transfer code yields results suggesting that street lights account for about (14 ± 1)% of light emissions resulting in skyglow seen over the city. A separate derivation from first principles implies that street lighting contributes only 2−3% of light seen at the zenith over Tucson. We discuss this inconsistency and suggest routes for future work.

Los Angeles noise array—Planning and design lessons from a noise sensing network

The interaction between environmental noise and the built environment is an often-neglected area in the practice of urban planning and design. Most quantitative research is limited to single value loudness metrics and ignores the more complex spatial nuances of the noisescape. Qualitative soundscape research, on the other hand, is difficult to generalize to the urban scale. We report on an exploratory noise sensing project in Los Angeles, CA that investigates both qualitative and quantitative aspects of the noisescape. Using an experimental array of noise sensors mounted on city street lights, we collected preliminary data that demonstrate the promising and revealing nature of spatially and temporally granular urban sound data. By analyzing sounds in various frequency bands at different resolutions, we investigate how aspects of urban design such as landscaping, material choice, and building typologies impact the sonic environment. Our results reveal the spatio-temporal structure of low-frequency noise in traffic-exposed areas; a phenomenon not captured by traditional A-weighted decibel metrics. Based on these results, we present a model predicting noise based on historic traffic data. These results provide insights for future methods that can be applied to long-term policymaking and planning decisions.

Opinion: The importance of developing city street lighting maps

Opinion: The importance of developing city street lighting maps

From Municipal Socialism to Public Authorities: Institutional Factors in the Shaping of American Public Enterprise

In 1914 Daniel Hoan, the socialist city attorney of Milwaukee, pronounced regulation of public utilities a “complete fizzle.” Hoan's conclusion was based on years spent battling the imperious Milwaukee Electric Railway and Light Company with the limited legal tools at the city's disposal. He argued that even in Wisconsin, where regulatory agencies were at their most efficient and honest, it was impossible for public utility commissions to force good service at moderate cost from investor-owned companies. Commissioners would only push so far, realistically fearing they might drive private capital out of the state. Thus, in Hoan's opinion, the only sensible course was “to secure the democratic control of collectively owned property.” Despite this conviction and his astonishingly successful political career—spanning thirty years as an openly socialist public official, including twenty-four as Milwaukee's mayor—he retired from politics in 1940 having socialized only a stone quarry and the city's streetlights. As with many other local socialist officeholders in the United States, Hoan left a robust legacy of honest, efficient, and humane administration. But when it came to expanding public ownership, his record was meager.1

The Impact of Public Lighting on Voltage Distortion in Low-Voltage Distribution Systems

Harmonic distortion has become a main concem in electric distribution systems during the last years. Several public utilities are experiencing harmonic problems on their networks and some of them started to monitor the situation of the MV and LV distribution networks. Recently, the operation of the MV and LV networks of the AEM Torino (the city utility) have been investigated with several on-site measurements. The survey led to the observation of a step increase in voltage distortion on LV feeders when the city street lighting is switched on and, vice versa, a sudden decrease when it is switched off. This phenomenon can be mainly traced back to the resonance, under certain conditions, between the capacitance of the capacitors for the improvement of the lamps' power factor and the inductance of the MV/LV transformer. This work investigates the phenomenon both from a theoretical point and with laboratory and field tests. Some possible remedies and their practical implementation to reduce harmonic distortion are discussed.

The impact of public lighting on voltage distortion in low voltage distribution systems

Harmonic distortion has become a main concern in electric distribution systems. Several public utilities are experiencing harmonic problems on their networks and some of them started to monitor the situation of the MV and LV distribution networks. The operation of the MV and LV networks of the AEM-Torino (the city utility) has been investigated with several on-site measurements. The survey led to the observation of a step increase in voltage distortion on LV feeder when the city street lighting is switched on and, vice versa, a sudden decrease when it is switched off. This phenomenon can be mainly traced back to the resonance, under certain conditions, between the capacitance of the capacitors for the improvement of the lamps power factor and the inductance of the MV/LV transformer. This work investigates the phenomenon both from a theoretical point and with laboratory and field tests. Some possible remedies and their practical implementation to reduce harmonic distortion are discussed.

Users' Fees for Maintenance of City Street Lights

Users' Fees for Maintenance of City Street Lights

Astronomical clock controls city's street lights: Popular Mechanics, March, 1927, p. 399

Astronomical clock controls city's street lights: Popular Mechanics, March, 1927, p. 399