By Supun Dias
There are more than 700,000 street lamps in Sri Lanka consuming 150 Giga watt hours of electricity annually. Any commuter on the streets of Colombo or the outstation areas will witness a number of these lighting apparatus alight during broad daylight. This mismanagement and waste is due to the fact that traditional methods are still used by the local authorities to manage the switching on and off, of these street lamps. As Sri Lanka journeys towards green energy goals for 2020 there is an immediate need for a solution to this wasteful system. The Industrial Technology Institute (ITI) has invented an Automated Street Lamp Management System, using local technology, to solve this irksome issue.
Where do we start?
An annual loss of Rs.2,673 million is incurred by the Ceylon Electricity Board (CEB) on account of the lack of a proper street lighting management system. Also it is necessary to cut down all the wastage of electricity, as a country, considering the increasing energy prices and impending energy crisis.
There are two ways to reduce the electricity consumption by street lamps. Find alternatives for street lighting by introducing low-energy street lighting infrastructure or minimizing the energy wastage while keeping the same infrastructure. The global trend is to reduce the energy consumption from the main grid by using LED Street lamps fixed with solar cells.
However, exorbitant initial investment on solar panels and LED street lights prevents countries such as ours from doing so. Therefore it is necessary to find or locally develop an appropriate technology to reduce the wastage of energy while keeping the existing street lamp system going.
One reason why we see a number of street lamps remaining switched on during day time is the inadequate routine maintenance, and the manual operating of on/off switches of the streetlamps attributes to the energy wastage in each case.
The experts at the Industrial Technology Institute told the Daily Mirror that on average street lightis are kept on for more than one and a half hours everyday—due to the inevitable delays of manual operation. In the city of Colombo alone there are 13,000 street lamps, which when multiplied by this excess of one and a half hours, consume up to 1.3 Giga watt hrs annually. The experts claim that this is the equivalent of shutting down the Matara Thermal power plant for three days. This would no doubt make a considerable impact on the electricity consumption with no real need.
With the aim of making a dent on the energy consumption of the street lamp network, Research Engineers and Research Scientists at the Electro Technology Laboratory of the Industrial Technology Institute (ITI) developed the street lamp management system. They came up with two types of Street Lamp Management Systems; one based on a timer and the other based on a radio frequency controlled remote on/off switching system.
The timer-based system switches on and off in response to signals emitted by the timer fixed on-location. Switching on/off times are encoded considering the seasonal changes. During December and January when night falls early, street lamps with the timer switch on early and during the season with longer daytime, as in April, the lamp switches on later based on the duration of day light.
Taking practical steps towards a greener future
The first phase of the pilot run for the timer-based Street Lamp Management System is already completed and the pilot run was conducted by installing ten units along Bauddhaloka Mawatha, Colombo 07, and is performing successfully. Currently discussions with the CEB officials are underway to commission the Timer Based Street Lamp Management System in one of CEB’s existing projects.
The Colombo Municipal Council (CMC) has shown interest in the project as they also operate a large number of street lamps within the Colombo City. ITI is now looking for local stakeholders such as the CEB, Provincial Councils, Pradeshiya Sabhas as well as the Road Development Authority (RDA) which also operate a large number of street lamps. One switch is able to control around 20 street lamps.
As an improvement to the Timer Based System, researchers of ITI innovated a method to control street lamps by using normal radio frequency. In the Radio Frequency (RF) Controlled Street Lamp Management System street lamps are switched on/off in a response to a pre-defined audio signal pattern which is transmitted along with ordinary radio signals broadcast by a radio station.
The advantage of this system is the ability to control all the street lamps in the island remotely from one place. However, according to the climatic differences of regions switching on/off times could be changed based on the new system developed by ITI.
Laboratory-scale experimental studies for this system have been completed at the ITI very successfully with the technical collaboration of engineers at Sri Lanka Boradcasting Coporation (SLBC) and ITI research team is now looking for the patronage of a government or private organization or an individual for pilot scale implementation. Patenting the RF Controlled Street Lamp Management System is now in progress.
More importantly, the technology for managing the street lamp system to reduce energy wastage to a minimum, through a timely switching process is developed and available in the country. Now is the time to apply it for the common good.
The system was developed by a team comprising R.A .S Devapriya, R M Weerasinghe, M.S.M Aroos, Thejani Fernando, Nuwan Darshana and Sisira Perera. Additional Director-Technical Services A.S Pannila worked as the project advisor.
Homegrown technology is the best solution
It is a long-acknowledged fact that in Sri Lanka we don’t give due prominence to our inventors; however in this instance it is imperative that we change this negative trend. The technology created by the ITI is both practical and adaptable to local conditions and therefore it is necessary that prime place be given to these innovators to make a lasting impact on the energy consumption of this country.