Some of the world's biggest technology and telecommunications companies are still lagging behind in their use of renewable energy when compared to some of their closest peers.
The United States Environmental Protection Agency (EPA) has listed the top 30 largest green power users among the tech and telco partners of the Green Power Partnership.
Even though Google, Digital Realty, Equinix, Dell, Rackspace US and Samsung are among the top 10 companies with the largest renewable - or green - power usage, all of them currently draw less than 50 per cent of their power from green sources.
However, Intel, Microsoft, Apple and Cisco currently use 100 per cent green energy sources to power their business.
According to a study by Technavio, the global green data centre market is expected to reach US$ 55 billion by 2021.
Here are the top 10 energy consumers operating in the US tech sector, according to the EPA, and how much power they draw from renewable sources:
No. 1 - Intel
Annual green power usage (kWh): 3,804,034,623
Green power as a per cent of total electricity use: 100 per cent
Green power resources: Biomass, geothermal, small-hydro, solar, wind
No. 2 - Microsoft
Annual green power usage (kWh): 3,344,727,000
Green power as a per cent of total electricity use: 100 per cent
Green power resources: Solar, wind
No.3 - Google
Annual green power usage (kWh): 1,763,588,904
Green power as a per cent of total electricity use: 47 per cent
Green power resources: Biogas, small-hydro, solar, wind
No. 4 - Apple
Annual green power usage (kWh): 1,173,352,630
Green power as a per cent of total electricity use: 100 per cent
Green power resources: Biogas, biomass, small-hydro, solar, wind
No. 5 - Cisco
Annual green power usage (kWh): 1,109,490,995
Green power as a per cent of total electricity use: 100 per cent
Green power resources: Solar, wind
No. 6 - Digital Realty
Annual green power usage (kWh): 719,761,000
Green power as a per cent of total electricity use: 25 per cent
Green power resources: Wind
No. 7 - Equinix
Annual green power usage (kWh): 571,084,274
Green power as a per cent of total electricity use: 43 per cent
Green power resources: Wind
No. 8 - Dell
Annual green power usage (kWh): 212,413,724
Green power as a per cent of total electricity use: 27 per cent
Green power resources: Biogas, solar, wind
No. 9 - Rackspace US
Annual green power usage (kWh): 113,641,000
Green power as a per cent of total electricity use: 36 per cent
Green power resources: Wind
No. 10 - Samsung
Annual green power usage (kWh): 113,000,000
Green power as a per cent of total electricity use: 14 per cent
Green power resources: Wind
Honourable mentions
Other notable technology companies ranked by the EPA that don't consume as much power as the top 10, but draw 100 per cent of their energy needs or more from renewable sources include SAP America, Workday, Autodesk, Acer America and Netflix, which somehow sources 298 per cent of its energy requirements from renewables.
At the same time, some tech companies still appear to have a long way to go, with Lenovo claiming 35 per cent of its energy needs from green sources, Nokia just eight per cent and VMware with about half.
Additionally, Salesforce gets 30 per cent of its energy from green sources and Pitney Bowes claims 40 per cent, according to the EPA.
Number seven on the list, Equinix, was recently named as the top data centre operator in Cloudscene’s Q2 leaderboard, which ranks the top ten data centre operators in Oceania, Asia, EMEA and North America.
In January, Greenpeace International said Apple, Google, Facebook and Switch are among the companies taking the greatest strides towards 100 per cent renewable energy, while Netflix, Amazon Web Services and Samsung were lagging.
"Amazon continues to talk a good game on renewables but is keeping its customers in the dark on its energy decisions. This is concerning, particularly as Amazon expands into markets served by dirty energy," said Greenpeace USA senior IT analyst, Gary Cook, said at the time.
