Researchers have invented flags that are capable of generating electricity, using solar and wind power. These innovative solar and wind energy harvesting flags have been developed using flexible piezoelectric strips (which allow the flag to generate power through movement) and flexible photovoltaic cells (used to generate power, via solar cells).The research, conducted at The University of Manchester, is the most recent and advanced of its kind. The first to simultaneously generate wind and solar energies using inverted flags.
The purpose of the research is to provide cheap and sustainable energy generating solutions that can be easily deployed with little human interference and maintenance. This design strategy is popularly known as the “deploy-and-forget”, and has been proposed as the model, smart cities will employ, using remote sensors. These novel energy harvesting flags are capable of powering small-scale portable electronics and remote sensors for monitoring environmental parameters
Dr Mostafa Nabawy, co-author of the study, says: “Our piezo/solar inverted flags were capable of generating sufficient power for a range of low power sensors and electronics that operate in the micro-Watt to milli-Watt power range within a number of potential practical applications in avionics, land and sea remote locations, and smart cities. We hope to develop the concept further in order to support more power-demanding applications such as an eco-energy generating charging-station for mobile devices.”
“Wind and solar energies typically have intermittencies that tend to compensate each other. The sun does not usually shine during stormy conditions, whereas calm days with little wind are usually associated with shiny sun. This makes wind and solar energies particularly well suited for simultaneous harvesting, with a view at compensating their intermittency.”
According to Jorge Silva-Leon, from Manchester’s School of Mechanical, Aerospace and Civil Engineering and lead-author of the study, “Under the action of the wind, the flags we built bend from side to side in a repetitive fashion, also known as Limit-Cycle Oscillations.
This makes them perfectly suited for uniform power generation from the deformation of piezoelectric materials. Simultaneously, the solar panels bring a double benefit: they act as a destabilizing mass which triggers the onset of flapping motions at lower wind speeds, and of course are able to generate electricity from the ambient light
The research has been published in the Journal Applied Energy.