Lighting is the most visible form of electricity consumption and lighting load in our country is very high – about 17-18% of total load. By increasing the efficiency of lighting system, there can be significant energy saving and reduction in peak load. There is a scope for reducing about 30 to 35 % of the morning and evening peak demand.

Best practices in lighting systems may be achieved by:

 Installation of energy efficient fluorescent lamps (T-5) in place of conventional fluorescent lamps (T-12).
 Installation of Compact Fluorescent Lamps (CFLs) in place of incandescent lamps.
 Installation of LED panel indicator lamps in place of filament lamps.
 Installation of high frequency (HF) electronic ballasts in place of conventional magnetic ballasts.
 Use of high efficacy light sources for reducing the energy consumption for lighting .
 Solar lighting systems are providing to be a viable option in rural India because the technology involves no moving parts, low maintenance, and simple to operate.

Following factors should be considered while urban lighting system is to be design:

 Use of high-efficacy light source
 Use of more efficient luminaries
 Selective switching
 Utilisation of daylight
 Luminaries of higher space to height ratio
 Higher reflectance surfaces of the room
 Visual task analysis
 Task oriented lighting.

In order to achieve the energy efficiency in urban lighting systems, following points can be considered:

 Use of LED lamps for indicating lamps will reduce the energy consumption.
 Use of CFLs in place of incandescent lamps, reduce the lighting energy by 70%.
 Use of mirror optic fluorescent lamps increases the lighting level considerably.
 Use of HPSV lamps in place of MPSV lamps reduce the energy consumption by 60%
 As the lighting level is inversely proportional to square of the distance, optimising the height of lamp will aid in reduction of lighting energy.
 Use of electronic ballasts for discharge lamps, reduce energy consumption by 20%
 Installation of intelligent lighting controller helps in controlling the lighting energy.
 Use of photo sensor switch for streetlight controlling helps in conserving the lighting energy.
 Installation of auto cut-off switch to put off lights during lunch hours at the office buildings will reduce the lighting energy.
 At streetlights, in many places, the reflectors inside the HPSV fitting are damaged, it is suggested to replace the fittings with anodised aluminium reflectors. This will improve the lighting level by 20 to 25%.
 Use of energy efficient lamps like CFL, LED, T-5 fluorescent lamp, etc lead to enormous amount of energy savings which is estimated as 50 to 80%.
 Electronic gears of conservation of energy like electronic ballast saves energy within the range of 10 to 20%.
 Solar lighting systems such as lanterns, streetlights, home lights, etc. can be effectively used, especially in areas of where lighting is required for shorter duration. This will not only lead to energy conservation but also encourage use of non-conventional and environmental friendly energy system.

Energy efficiency in buildings and street lighting are becoming important in today’s era. An intelligent urban platform including system management, information assurance, and application services between utility and consumers can play a critical role in order to achieve energy efficiency in these areas.

Figure 1: General block diagram of urban lighting platform

Energy efficiency in buildings requires data concentratorplus-real time platform. The integration of the real time platform software on the data concentrator allows real time data acquisition processing and distribution capabilities.

Intelligent urban platform delivers following energy data:

 Real time data monitoring
 Hourly, daily and monthly data aggregation.
 Temperature, luminosity and humidity data average
 Energy data comparison with previous periods
 Cost/CO2 energy consumption equivalence are required to collect for energy efficiency in buildings.

As per the architecture (Fig 2), multimodal data collection is required and further monitoring and analysis is required. For an intelligent urban lighting, let two clients have been implemented in order that end-users can interact with the lighting solution. Lighting maintenance staff (web-based client) may communicate with lighting operator (desktopbased client). Analysis of the lighting can be done by different lighting conditions and wireless communication interface can also be done. After laboratory deployment, with different lighting conditions, and demonstrator framework, it can be put up in real scenario. Smart lighting will be based on environmental parameters and energy consumption (2-5 street lamps) in real scenario. After testing of algorithms processing mobility information its integration with other inter-domain services through the platform (15-20 street lamps) can be done.

Recent steps taken by India for urban and rural lighting

Pradhan Mantri Sahaj Bijli Har Ghar Yojana – ‘Saubhagya’ – a new scheme was launched by the Prime Minister Narendra Modi to ensure electrification of all willing households in the country in rural as well as urban areas for lighting on 25th September, 2017.

The objective of the ‘Saubhagya’ is to provide energy access to all by last mile connectivity and electricity connections to all remaining un-electrified households in rural as well as urban areas to achieve universal household electrification in the country.

Figure 2: Intelligent urban platform

The electricity connection to households include release of electricity connections by drawing a service cable from the nearest electricity pole to the household premise, installation of energy meter, wiring for a single light point with LED bulb and a mobile charging point. In case the electricity pole is not available nearby from household for drawing service cable, the erection of additional pole along with conductor and
associated accessories shall also be covered under the scheme.

Similarly, in urban areas, Integrated Power Development Scheme (IPDS) provides for creation of necessary infrastructure to provide electricity access but some households are not yet connected mainly on account of their economic condition as they are not capable of paying the initial connection charges. Therefore, Saubhagya has been launched to plug such gaps and comprehensively address the issues of entry barrier, last mile connectivity and release of electricity connections to all un-electrified households in rural and urban areas.

Project proposals shall be prepared by the State DISCOMs or power departments and sanctioned by an inter-ministerial monitoring committee headed by Power Secretary. The electrification works under the sanctioned projects shall be executed by respective DISCOMs or power department through turnkey contractors or departmentally or through other suitable agencies capable of doing this work as per norms.

In order to hasten the process of release of connections to urban households, camps would be organised in urban or cluster of villages for identification of beneficiaries using modern IT technology with a Mobile App or web portal. Application for electricity connections shall also be registered electronically and requisite documentation including photograph of applicant, copy of identity card and/or details such as Mobile number, Aadhaar number, bank account number etc. shall be completed on spot in the camps, so that connections are released at the earliest. The Gram Panchayat or public institutions in rural areas shall also be authorised to collect application form, complete documentation and also for distribution of bills, collection of revenue and other activities, as applicable.

Urban Jyoti Abhiyan (URJA) is also addressing the issue of urban lighting.

Digitalising urban lighting

In implementation of streets or walkways are minimally lit until a vehicle or pedestrian triggers a sensor signal, thus causing the lights to peak for a brief period. The selection of conceivable systems is large, ranging from presence detectors and video cameras to interlinked lighting and energy infrastructures that take traffic volume as well as the feed-in of renewable energy sources into account. The main aim of these new lighting concepts is to save energy.

LED plays a key role in any discussion about the future of public lighting. The beaming chips mark the transformation from electric lighting to electronics. While in traditional light sources gas is discharged or a glowing filament radiates light and heat, solid state lighting technology like LEDs and the organic OLEDs is based on electroluminescence. Diodes are especially advantageous for lighting control and system solutions because they can be gradually dimmed from zero to one hundred percent or quickly switched on and off. In contrast, gas-discharge lamps take minutes until they reach their full level of brightness, therefore making high switching frequencies impossible.

Recent technical developments serve to promote the digitalisation of public lighting. Along with these technical innovations socio-political questions arise that reach far beyond such functional aspects as security, or the need for a certain light colour or product design. The growing demand for ‘intelligent’ control systems and high-quality light give rise to more general questions like: Which criteria should be followed to evaluate public lighting? What is the basis for discussing and negotiating the various concerns?

‘The right light at the right time in the right place’, is a goal that lighting designers, city planners, manufacturers and politicians share. But it is not yet clear who is to judge and decide which light is considered to be the best suited one. Light sensitivity varies not just from person to person but also in a cultural sense. What methods should be used to identify the ‘right light’, and where and when it can be dimmed or even switched off?

Looking at a particular urban space, the question of appropriate lighting is as complex as the specific local situation. Public lighting infrastructures can only be linked and controlled when, in addition to the organisational and technical hurdles, urban spaces are also considered as meaningful places that fulfil social functions. Aware of the challenges ahead, light planners and developers are showing an interest in social science research on the night time city and the night time activities of users of public spaces. There is the need for sociological research in order to develop scripts for digital lighting solutions. So, the digitalisation of public lighting may also offer a new and challenging field for social and urban studies.

Conclusion

In this article, authors have given brief information about energy efficiency aspects. In the second section, an intelligent urban lighting platform is provided with block diagram. If the urban lighting scheme is designed properly, it can enhance energy efficiency and provide sustainability in lighting sector. The importance of energy efficiency in lighting sector is also explained. In the last section, recent steps taken by the Indian government in terms of India for urban and rural lighting is also explained in brief.