How much power does the Internet consume?

In Shakespeare's time, delivering a message to someone in another city was a major undertaking. You had to hire someone to transport it, often involving a journey that could span many miles. This trip might be perilous, especially for Shakespearean couriers, who often had a 50% survival rate in the tragedies.

Back in Shakespeare’s era, every communication required significant effort from the moment it was written to the time the recipient received it. Today, however, the process is far more efficient. A quick boot of a computer, tablet, smartphone, or video-game console lets you send multiple messages in minutes, reaching the recipient almost instantly. Just think of all the effort saved!

However, when it comes to actual energy consumption, the Internet is quite a power-hungry system. It's made up of interconnected networks, each containing numerous computers that consume substantial amounts of power. But can we truly measure the electricity the Internet uses?

To calculate the energy consumption of the Internet, we must take into account every device connected to the network. The Internet consists of billions of devices. Let’s begin by looking at data centers.

Hamsters and Elephants

Data centers are clusters of computers that serve as the backbone of many systems. A data center may not always be connected to the Internet – some are internal to a company or organization. However, the Internet depends heavily on vast data centers filled with hundreds of thousands of computers.

A data center can house database servers, Web servers, mainframes, or a mix of all these types. In the past, it was common for businesses to operate their own data centers. Some were enormous, the size of a warehouse, packed with rows of computers, while others were smaller with just a single rack of machines.

Today, many companies instead turn to cloud services for their data storage and computing needs. This means they outsource the physical infrastructure to another company that owns the devices. Access to the company’s data and services is facilitated through the Internet. Cloud data centers are massive, housing hundreds of thousands of machines in vast buildings.

Cloud service providers store customer data across multiple machines to ensure redundancy. This means that if one computer fails, the data is preserved on another. However, each computer still needs power to function.

Computers also produce heat, which can be problematic. Excessive heat can cause electronic components to malfunction. To prevent this, data center operators must implement cooling systems, with air conditioning being the most common choice. These cooling systems are essential, and we must account for their energy use when estimating the Internet's total power consumption.

Since 2008, the number of data centers in the U.S. has decreased [source: IDC], primarily due to businesses transitioning to cloud services and outsourcing their data centers. However, the remaining data centers are expanding in size. It’s like replacing 50 hamsters with 10 elephants – fewer animals, but they occupy far more space and consume much more energy.

It’s impossible to get an exact count of data centers, as many companies keep their data center information private for competitive reasons. Additionally, we can’t know for sure how much energy each data center uses without knowing all the specifics. But that hasn’t stopped people from attempting to estimate the Internet’s power consumption. Next, we’ll explore some of the methods used to make these estimates.

Measure Twice, Bill Once

In 2011, Barath Raghavan and Justin Ma from ICSI and the University of California, Berkeley, set out to estimate the electricity consumption of the Internet. They aimed to include not just the energy used by the Internet itself but also the power required to build the necessary infrastructure. This included computers, network connections, cell towers, and other hardware. They referred to this total as embodied energy, or 'emergy.'

Raghavan and Ma based their work on broad estimates and openly stated that their calculations were not perfectly accurate. Their primary intention was to raise awareness of the issue and encourage further exploration. Their estimates included:

They also considered other components of Internet infrastructure. For each device category, they assigned a range of energy values, accounting for the variability in energy consumption depending on the type of device. Additionally, they factored in the typical life span of each piece of infrastructure.

Ultimately, Raghavan and Ma estimated that the Internet consumes between 84 and 143 gigawatts of electricity each year, which accounts for about 3.6 to 6.2 percent of global electricity usage. When considering emergy, the total energy consumption rises to 170 to 307 gigawatts. Although this is a significant amount of energy, it still represents less than two percent of the world’s total energy consumption.

Should We Shut It Off?

A 2012 New York Times article by James Glanz explored how data centers can be highly inefficient and consume large amounts of energy. To ensure reliability, data centers must duplicate information across multiple machines, ensuring redundancy. These systems need to be continuously operational and accessible. In addition to the constant power required by servers, the cooling systems in data centers also demand considerable energy.

According to Glanz's sources, data centers consume roughly 30 gigawatts of electricity [Glanz]. He also reports that a large portion of this energy is wasted—up to 90 percent. With so much energy being squandered, one might wonder: is the Internet doing more harm than good?

Not according to Raghavan and Ma. In their report, they emphasize that the Internet’s energy use is a mere fraction of that of the transportation sector, which accounts for 61 percent of all oil production [source: Raghavan and Ma]. The researchers argue that, since the Internet uses less power and has a smaller environmental impact than transportation, it makes sense to shift more activities online. For example, using teleconferencing instead of traveling for meetings could save significant amounts of energy.

The true picture of the Internet’s energy consumption reveals that it’s a multifaceted issue. Without the Internet, we’d have to turn to other methods of communication and data access, which could potentially use more energy and produce more pollution. If that’s the case, it makes sense from an energy standpoint to decrease our dependence on those alternatives and shift our focus more toward the Internet.