Carbon emissions cause climate change. Intelligent policy in the public and private sectors works to reduce CO2 emissions - through actions as varied as the recent EPA actions to throttle back atmospheric pollution from power plants to energy efficiency programs that reduce the need for electricity. Innovative technologies that improve grid awareness and consumer awareness of electricity consumption also help to reduce emissions and energy costs. But in a very real sense, all of these solutions merely ameliorate the dilemmas caused by a growing global demand for energy. The real problem is the material foundation for our modern society – silicon.
Silicon runs the world as the most common material used for semiconductors, sensors, and data storage that runs grids, communications networks, vehicles and just about everything that has a display or mobile connection. From a Smart Grid perspective, semiconductors are used for energy collection, conversion, storage, transmission and distribution, and consumption.
Silicon is cheap and readily available – it is the second most common element found on Earth and it is easily manufactured on a large scale. Silicon is an excellent conductor of heat and it consumes a lot of electricity – some electricity powers a semiconductor and the rest cools the components. Power consumption is a major constraint in contemporary chip design. And then there’s the expansion of data centers as storage centers for cloud-based solutions and engines for the internet. A recent study* identified that global power requirements grew by 63% to 38 gigawatts (GW) from 24GW in 2011. Cooling costs make up about 30% of the total electricity bill for large data centers.
We increasingly rely on intelligent electronics in our connected and mobile economy, which means a proliferation of silicon-based processors, memory, and sensors. These devices are estimated to waste 15 terawatts (TW) globally now– mostly as lowgrade waste heat that cannot be captured for any other purpose (such as application in a combined heat and power system). That number will only grow as our reliance on electricity and electronic devices increases for world populations.
So it is no surprise that the search is on to find a better material than silicon – one that is much more “energy-efficient” and less likely to produce waste heat. Groundbreaking discoveries in materials science – the composition of things – promises a truly ironic possibility – that a different form of carbon can be a global answer instead of a global problem. Graphite and diamonds are the two physical representations of carbon. And while diamonds may be a girl’s best friend today, in the long run, graphite may be everyone’s best friend. Graphene is derived from graphite.
Graphene is an unrolled carbon nanotube. It is extremely strong, extremely flexible, and extraordinarily high thermal conductivity – meaning it does not produce the heat buildup like that produced in things made from silicon. Carbon is the 15th most commonly occurring element - it is not a rare earth material. This video provides the best explanation of graphene.
Graphene has interesting potential as a replacement for silicon. Not only can it “run cooler” than silicon, but it also has versatility to perform as a good energy harvesting material too. It’s attracting R&D investments ranging from $1.3 USD committed by the European Commission to increased funding by companies such as IBM and Samsung. Of course, R&D activity is a far cry from commercially available products, but we’ve seen the same path trodden for many innovations – such as solar photovoltaics. What initially is expensive and difficult to scale up and cost-effectively manufacture startles all observers with its rapid pace of technology advances and cost reductions.
Will graphene replace silicon? If it can perform just as well with a lower energy demand than silicon, then the answer is probably yes. If it can perform better than silicon with lower energy demand, then the answer is absolutely yes. And if that’s the case, it is one technology that will be just as disruptive to manufacturers and solution providers as it will be to utilities.
* DatacenterDynamics 2012 Global Census