Powering computers and all our devices requires us to use batteries if they can’t be connected to a power source/electrical socket. For the most part this means that we use NiCa or Lithium batteries. The problem with this is that they require us to use rare earth metals that are hard to find and process, which makes them expensive and mining the metals are potentially bad for the environment. The other problem is that they need frequent replacement and create a lot of waste. Due to this a lot of effort is going on to find better ways of generating power.
Now, Christopher Howe and other researchers from the University of Cambridge have managed create a power source using blue-green algae to generate enough electricity to power a processor performing calculations (to simulate load). Using a type of cyanobacteria called Synechocystis sp. PCC 6803 sealed in a container about the size of an AA battery, made of aluminum and clear plastic they were able to generate the 0.3 microwatts of power to run the CPU for 45 minutes followed by 15 minutes of standby, which required 0.24 microwatts of power.
The system ran without additional intervention for 6 months and the computer was placed on a windowsill at one of the researchers’ houses during the test and the ambient light was enough to power the processor. There are indications that this can be scaled up to generate more power for more resource intensive applications but even if that doesn’t work out, the current setup could potentially be used to power IoT devices that don’t require that much power to run such as sensors/monitors deployed in the forests/cities for monitoring.
Sustainable, affordable and decentralised sources of electrical energy are required to power the network of electronic devices known as the Internet of Things. Power consumption for a single Internet of Things device is modest, ranging from μW to mW, but the number of Internet of Things devices has already reached many billions and is expected to grow to one trillion by 2035, requiring a vast number of portable energy sources (e.g., a battery or an energy harvester). Batteries rely largely on expensive and unsustainable materials (e.g., rare earth elements) and their charge eventually runs out. Existing energy harvesters (e.g., solar, temperature, vibration) are longer lasting but may have adverse effects on the environment (e.g., hazardous materials are used in the production of photovoltaics). Here, we describe a bio-photovoltaic energy harvester system using photosynthetic microorganisms on an aluminium anode that can power an Arm Cortex M0+, a microprocessor widely used in Internet of Things applications. The proposed energy harvester has operated the Arm Cortex M0+ for over six months in a domestic environment under ambient light. It is comparable in size to an AA battery, and is built using common, durable, inexpensive and largely recyclable materials.
Their research has been published in the Energy & Environmental Science journal and work is ongoing to build on top of it to look at commercial applications.
Source: A colony of blue-green algae can power a computer for six months
– Suramya