Want to reduce your electricity bills? Then run your electrical appliances on preplanned schedules. This is what a study by a team of researchers from the Indian Institute of Science (IISc) have found. But there is a caveat: this is possible only when our homes are fitted with smart meters that can monitor our consumption pattern.
In a smart grid system, the electricity distribution company publishes prices a day before. The day is divided into timeslots and there are different prices for different timeslots. For example, the rates per unit may be lower in early morning hours and higher for peak evening hours. Running appliances in time slots with lowest cost would reduce bills, but it may not be always convenient to do so. For example, it is not convenient to have a dishwasher running during lunch time. Earlier automatic schedule schemes optimised cost but convenience was not taken into account. Recent work by Mannam Rama Rao, research scholar at the Department of Electronic Systems Engineering, is the first one to also consider user convenience. The study was led by Profs Joy Kuri and Dr. T. V. Prabhakar, Department of Electronic Systems Engineering, IISc. The user can specify the time slots that are convenient for different appliances. The best schedule is calculated, taking into account the cost and user preferences.
A smart grid system with pricing information shared in advance has many advantages. It helps the electric company balance the demand and supply, helps consumers reduce their power bills and increases the general efficiency, stability and reliability of the system. For the scheme to be successful, it is important that consumers learn about the system. “The main advantage depends on how transparently the scheme is implemented by the utilities and of course, user awareness. Awareness programs are essential to attract energy consumers towards these new schemes. If everything goes smoothly, the profits can be shared by all players of the grid,” explained Rama Rao.
The distribution companies face huge losses due to demand and supply imbalance. If the demand increases a lot for a short time, the supply company needs to use secondary sources that are generally expensive. In a flat billing scheme, the supply company needs to bear the extra cost, and hence operate at lower profit margins. However, if the day ahead pricing scheme is implemented, consumers can schedule loads in off-peak hours. This will not only help consumers reduce their bills, but also reduce the operating costs of the distribution companies.
When supply companies have schemes to match demand and supply, it is called Demand Side Management (DSM). Researchers calculated energy consumption bills for a model household. They observed that the cost without DSM was about 15% more than when an Energy Consumption Scheduler (ECS) was used with DSM. “An Energy Consumption Scheduler (ECS) will sit inside the smart meter to make the scheduling decisions on behalf of the consumer,” informed Rama Rao.
Currently, few companies in India offer demand side management. For example, BESCOM (Bangalore Electricity Supply) offers time-of-the-day scheme for HT consumers. This is not the same as day ahead pricing, but it is a strategic step towards creating customer awareness about scheduling loads. “We believe that as Advanced Metering Infrastructure (AMI) gets implemented throughout the world rapidly, India is not far away from observing the same change,” commented Rama Rao.
About the Authors:
Mannam Rama Rao is a research scholar in the Department of Electronic Systems Engineering, Indian Institute of Science.
Prof. Joy Kuri and Dr. T. V. Prabhakar are faculty in the Department of Electronic Systems Engineering, Indian Institute of Science.
Contact: Prof Joy Kuri at +91 80 22933091