Fujitsu hybrid energy harvesting device generates electricity from heat or light

Using ambient energy (such as light, vibration, heat, radio waves, etc.) to produce electrical energy is being developed by many researchers around the globe. The folks from Fujitsu Laboratories Ltd. recently announced that they have developed a new hybrid energy harvesting device capable to generate electricity from either heat or light. Instead using multiple harvesting devices, this device enables energy derivation from two separate sources in a single device.

Since the amount of power available by energy harvesting is limited, there has been interest in utilizing multiple forms of external energy simultaneously (such as light and heat, or light and vibrations) in order to collect a sufficient amount for practical use. In the past, this has been achieved by combining different kinds of devices, which leads to use of more resources for the production and higher costs.

By changing the electrical circuits connecting two types of semiconductor materials (P-type and N-type semiconductors) the device can function as a photovoltaic cell or a thermoelectric generator. In addition, as it can be manufactured from inexpensive organic materials, device production costs can remain low.

Fujitsu Laboratories successfully developed an organic material that is suitable for a generator in both photovoltaic and thermoelectric modes. The organic material features a high generating efficiency that can produce power from even indoor lighting in photovoltaic mode, and it can also generate power from heat in thermoelectric mode. Since the organic material and its process cost are inexpensive, production costs can be greatly reduced.

Fujitsu Laboratories will continue with further development of this technology to increase the performance of hybrid devices, with aim to commercialize the technology by year 2015. They envision its application in areas where either the ambient light or heat is not sufficient to power sensors. Some of the examples are powering environmental sensors for weather forecasting in remote areas, or in medicine, where it could be used instead of batteries in order to power medical instruments that monitor conditions such as body temperature, blood pressure, and heartbeats.