A Low Cost Electronic Load for Renewable Energy Systems

A low cost electronic load for Renewable Energy Systems (RES) has been designed and tested as
part of a project on the monitoring and optimising renewable energy usage. This paper describes how MOSFETs, controlled by a microcontroller, can be used as linear loads to simulate the daily power consumption profile of a household. For test purposes, a prototype capable of dissipating 60W has been built: the obtained results demonstrate the load capability of simulating any household energy consumption profile. The simulation of load spikes and steps changes on a RES can also be performed in order to test the control and stability. The results show that the linearity of the load demonstrates favorable results compared to switched loads since much smoother energy profiles can be reproduced. A microcontroller has been used to enable the load to be connected to many different
applications. By increasing the dissipation capability, the load can greatly assist designers and researchers in the development and analysis of domestic scale RES. The total cost for a 2kW load unit is approximately a quarter of the cost of current, commercially available, programmable electronic loads.