The Electric Power Research Institute (EPRI), a non-profit research, development, and demonstration group funded by electric utilities, found that consumers who fully charge their iPad every other day can expect to pay only $1.36 a year for the electricity used to power their iPad.
This analysis shows that every iPad consumes less than 12kWh of electricity in the course of one year, assuming it is fully charged every other day. The EPRI compared this with energy consumption of other devices: an iPhone 3G uses 2.2kWh for a total of $0.25 a year, a 60W CFL light bulb at 14kWh comes to $1.61 a year , a PC laptop at 72.3kWh comes to $8.31 a year, and a 42-inch TV at 358kWh comes to about $41 a year.
This analysis was conducted in Knoxville, Tennessee, at EPRI’s power utilization laboratory, so costs may vary depending on the region a consumer lives in and the price of electricity at the particular location.
The EPRI then calculated the energy used by all iPads in the market and found that they amounted to 590 gigawatt hours, which is about the equivalent of a 250 megawatt power plant.
Vice President of Power Delivery Utilization at EPRI, Mark McGranaghan, explained that “these results raise important questions about how the shifting reliance from desktop to laptop to mobile devices will change energy use and electricity requirements for the information age. Our measurements indicate that new iPads will consume about 65 percent more electricity per year.”