New tool developed by ECE PhD student helps prepaid utility customers make informed choices

Millions of people in low-income households and developing regions around the globe rely on prepaid utility plans to get their electricity—instead of paying a power bill at the end of the month, they pay up front by depositing money into their accounts.

Those plans, however, can lead to hard tradeoffs, like rationing air conditioning or fans during heat waves to make sure the lights don’t go out. But a new model developed by Maitreyee Marathe, a graduate student in electrical and computer engineering at the University of Wisconsin-Madison, helps users navigate those choices.

Her new energy-management model, which can be run on an inexpensive $10 microcontroller, allows users to prioritize their energy needs. The model looks at their account balance and optimizes the use of each appliance based on the ratio of importance to how much energy it uses; the model may warn users to flip off the TV to save energy for the stove or to keep the fans running.

Maitreyee says the project could also be useful for traditional energy payers who need to stay within a budget and for people like solar power users in remote areas who may need to carefully ration the charge left in their battery.

Read the full story by Chris Hubbuch at the Wisconsin Energy Institute.