Google: Powering data centers with clean energy 24/7 'no easy feat'
- Google issued a white paper Wednesday examining the energy used to run its data centers, concluding that while it has purchased 2.6 GW of renewable capacity, more than sufficient to cover its demands for clean energy, the resources are not fully aligned with when the electricity can be delivered.
- The internet giant reached its 100% renewable energy purchasing goal on a global and annual basis last year, but says it will now tackle the "much more challenging" long-term goal of powering operations on a region-specific, 24/7 basis with clean, zero-carbon energy.
- Google's analysis showed none of its data centers in 2017 were matched 24 hours a day, every day with 100% carbon-free energy, though at least one is very close. In all, the company matched about two-thirds of its energy demand with carbon-free supplies.
Google's white paper and discussion of its data center energy use illustrates the extent to which corporate buyers are serious about reducing their carbon footprint, whether it be about environmental stewardship or simply the company's bottom line.
Several major technology companies are boosting their renewable energy use, but Google is already the largest corporate buyer in the world and its analysis shows how difficult it will be to eliminate all emissions from its footprint.
Google's data center in Hamina, Finland, utilizes almost entirely carbon-free energy. Overall, the white paper showed 97% of the center's consumption matched with the time when renewables were delivered. The company credits a competitive energy market that has allowed it to sign several wind PPAs in the region, and Finland's power grid which is heavy on carbon-free resources such as biomass, hydropower and nuclear.
But for those same reasons, that last 3% will be difficult to wring out.
"Adding more renewable energy may have a limited impact in reducing the electricity grid's CO2 emissions," according to Google, because the reductions will hinge on which marginal energy sources are displaced.
"Since the marginal generation source in the Nordic countries is often carbon-free hydropower, additional wind power may have the effect of displacing a fellow carbon-free resource," Google noted.
"The takeaway is that renewable energy additions are more likely to achieve substantial CO2 reductions in carbon-intensive regions, in particular where marginal power generation comes from fossil fuels."
On the other hand, in 2017, Google's data center in Lenoir, N.C., matched 67% of its energy use on an hourly basis with regional carbon-free sources. That's still significant, but going further will require more carbon-free energy at night.
"The daytime energy use of our data center is fairly well matched with carbon-free energy," the white paper points out. "However, our nighttime energy profile is noticeably more carbon intensive. ... Even in locations where renewables like solar and wind power are available, their variability means they are unable to provide power 24x7. This can be problematic in places where there are few carbon free sources to step in when sunlight and wind diminish."
The ultimate goal will be "no easy feat," Google concludes, likely requiring innovations in policy, technology and business models. While storage could help Google reach its goals, the company said it is unlikely to be a panacea.
"The deployment of cost-effective, large-scale energy storage could conceivably help create better matching of renewable energy supply with data center electric demand, particularly over the course of a day," the white paper explains. "However, storage may not necessarily be able to overcome major seasonal variations in renewable supply."
"We'll need policy and market reforms that break down barriers to carbon-free energy procurement, as well as new policies that recognize the societal importance of carbon-free energy and appropriately price the attributes of different power sources," the company wrote.
There is clearly an increasing interest in developing the resources. An August report from Bloomberg New Energy Finance found corporations had purchased 7.2 GW of clean energy so far in 2018, already topping the 2017 amount by almost 2 GW.
Large tech companies are particularly focused on renewables. Asked about its own plans, Amazon Web Services pointed to its sustainability web page. The company "is working to achieve its goal of 100% renewable energy usage for our global infrastructure footprint," and in January 2018, reached 50% renewable energy usage.
Facebook has committed to reducing greenhouse gas emissions tied to its operations by 75% and powering global operations with 100% renewable energy by the end of 2020. The social media giant says it is two years away from utilizing all-renewable energy.
Facebook is also "strongly committed ... to increasing the amount of new renewable energy added to the power grids where we operate data centers," the company told Utility Dive in a statement.
Similarly, Microsoft told Utility Dive that the company's goal is "more than just a percentage."
"Part of our strategy from day 1 was to buy local or regional renewable energy, rather than get to a set percentage as fast as possible and then work backwards to make it local," the computing giant said in a statement.
Microsoft said it has already reached a goal of 50% renewable energy by the end of this year, and is working toward 60% by the early 2020s.
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