Modern technology has afforded us many things we now take for granted. Many different aspects of our lives are so readily and easily afforded to us that we forget exactly what life was like without them. Mobile applications and portable devices offer an unexpected number of conveniences that are now somehow indispensable to our daily existence. Probably the most indicative of today’s dependence on technology is the USB port, which is used universally to transfer data and charge mobile devices.
There are over 10 billion USB devices in the world today. These devices have become so common that they’ve created an entire industry of weird offshoots since initially being introduced in the late 1990s. This includes a heart shaped USB mouse, a USB hand warmer, and a vast array of quirky USB flash drives involving everything from the avengers to odd looking Halloween themed flash drives. Nowadays, if even you’re doesn’t have a USB hook up in it, it’s basically out of date.
The worst part (or best depending on how you look at it) is that the USB is never done evolving. Just like when you finally get comfortable with your new smartphone a brand new one comes out, the USB technology is constantly improving as well. A recent article in The Economist notes that big changes are coming to USB technology in the next year or two in the form of USB Power Deliver, or USB PD. According to the article, in coming years, “USB cables will be able to provide power to bigger electronic devices. In the long term this could change the way homes and offices use electricity, cutting costs and improving efficiency.”
Currently the USB cables support only 10 watts of direct current (DC) just enough to charge the current generation of iPads, but the USB PD will permit up to an incredible 100 watts. The Economist argued that this could “presage a much bigger shift, reviving the cause of direct current (DC) as the preferred way to power the growing number of low-voltage devices in homes and offices.”
The global standard for electricity is alternating current (AC), promulgated by Nikola Tesla, which beat out DC for its ability to switch between different voltages and travel longer distances. However, AC power requires an adapter to power electronic equipment, which can lose valuable power during conversion (touch those black adapters and they’re warm) and run constantly, which is also wasteful to the environment.
Ajay Bhatt, co-inventor of the USB, has become somewhat of a star in the tech world of Intel since inventing the device to develop a universal port. Recently he said in an interview with IEEE Spectrum that USB PD, with power flowing in either direction will allow “a power source” and computing device to negotiate power delivery mechanisms, or the voltages and the current.” He continued to mention his thoughts on the idea for The Economist, saying “the computer can say ‘I need to start the hard disk now, so no charging for the next ten seconds.’”
One place where the DC’s power and cost-saving opportunities are already being realized is with large datacenters. According to Gigaom, Facebook utilized DC power in its Prineville, Oregon, data center and companies such as JPMorgan, Sprint, Boeing, and Bank of America have built DC datacenters. According to Greentech Media, DC-powered datacenters are 20 percent more efficient than standard AC datacenters. Purchase and installation cost of DC equipment is about 30 percent less. On top of that, most significantly, DC datacenters require 25 to 40 percent less floorspace because equipment can connect directly to backup batteries.
While USB PD may offer opportunities in energy efficiency and smart grid technology, it is also poised to have a direct impact on green energy production. DC networks work well with both solar panels and wind turbines, as both produce power at different times and in different amounts. AC grids require a constant voltage and solar/wind power must be converted through an adapter to enter AC grids. Along with the USB PD’s ability to run DC power, these two powerful changes have major implications all the way down to the household level.
According to the Energy Information Agency (EIA), the fastest growing portion of residential electricity use is consumer electronics and small appliances which accounts for between 15 and 30 percent of a residence’s consumption. Another article on IEEE Smart Grid notes that many of these devices have a conversion efficiency of no better than 80 percent and some low end devices have efficiencies as low as 65 percent in converting power. These losses come from converting AC power to DC power, which according to the article accounts for around five percent of all electricity used in the typical US home being lost to conversion of AC to DC power to run DC devices.
In a related post about this topic for TheEnergyCollective.com, Jessie Jenkins asks “So if you have a solar system at your home producing DC power, why are you converting it to AC and then back to DC to operate your electronics and charge your electric car? Should you be wiring up a DC circuit in your house as well to power all your DC electronics?” With the introduction of USB PD, this common query may become completely obsolete.