How to create carbon-free data centers
Neil Papworth, a software engineer at U.K. cell phone company Vodafone, sent the world’s first text message on Dec. 3, 1992. Received by his boss at the company’s holiday party, the text simply read, “Merry Christmas,” but it heralded a data revolution that has barely abated since then.
Today, some 20 billion messages are sent each day globally, and texting is just the tip of the iceberg when it comes to data use. According to IDC, the digital universe is doubling in size every two years and will reach 44 zettabytes, or 44 trillion gigabytes, by 2020. As billions more connected devices come online, the computing demand generated is expected to outstrip what today’s infrastructure can accommodate, with data-intensive technologies such as livestreaming, virtual reality, and artificial intelligence placing huge demands on the world’s data centers.
While the environmental costs associated with energy consumption rightly worry environmental organizations, they are also of particular concern to the IT industry. As much as 3 percent of the electricity created in the U.S. each year powers data centers, and the IT sector is among the fastest growing users of energy. Globally, around 10 percent of electricity goes toward powering the entire IT ecosystem—including data centers and communications networks, as well as the manufacture and use of computers and other connected devices. Global demand for electricity will double by 2060, according to a recent report from the World Energy Council, with fossil fuels still expected to be the leading source of that energy. This is especially troubling in places like China, where coal is still the predominant source of power.
The explosive demand for computing power presents a significant challenge for our industry: How can we reap the benefits of growing connectivity while reducing the energy demand of IT infrastructure? Clearly, the solution will require data center owners and operators to dramatically increase their use of renewable energy and come up with innovative technological thinking for a huge new population of connected citizens generating staggering amounts of data.
Relying on renewables
As the number of data centers grows to meet the rising demand for computing power, there has been a global push to reduce both the carbon emissions and energy consumption of these facilities, where cooling accounts for a large portion of the budget.
Renewable energy sources—such as wind and solar power—have played an important role in the plans many large IT companies have made to reduce their use of carbon-intensive energy. Google, for example, recently announced a series of new clean energy purchases that bring its total wind and solar capacity to more than 3 gigawatts—enough power to cover 100 percent of the energy it took to run its products in 2017. The tech giant struck deals with renewable energy producers, agreeing to buy the energy they generate, which in turn allows those companies to invest in building more wind and solar facilities.
Like Google, other large companies, including Hewlett Packard Enterprise, have committed to sourcing 100 percent renewable energy through the Climate Group’s RE100 campaign, a collaborative initiative of large companies around the world committed to sourcing all of their operational electricity from renewables. The campaign is designed to produce demand signals that shift markets in favor of clean energy and have an influence on the broader policy backdrop. The thinking is that these large companies, which are the biggest consumers of energy, can influence markets through their procurement and management decisions, driving the transition to a low-carbon economy.
Other organizations are championing the adoption of cleaner energy as well. The Corporate Renewable Energy Buyers' Principles, for example, seek to help the world’s leading companies, including HPE, better communicate their purchasing needs and expectations to the marketplace. And in the IT sector specifically, BSR’s Future of Internet Power initiative is working with leading tech companies to work toward an Internet powered by 100 percent renewable energy.
These organizations are making critical strides, but the challenge with renewable energy is that it is intermittent, and current energy storage technologies, such as batteries, are not efficient and require large footprints. Power generation technologies for renewables can require large footprints, too. For example, it can take several acres of solar panels to generate just one megawatt of power.
In fact, the path to carbon-free data centers is unclear for many companies. Data center operators that look to buy renewable energy from a local utility can find the amount and mix of renewables available to them varies from state to state. This means some data center markets could still rely heavily on carbon-powered electricity for a significant percentage of their energy.
Some data centers have even looked to achieve energy efficiency through best practices in their design and operations—a cost-effective option that is readily available now and offers a rapid return on investment. But the reality is, longer term, product efficiency improvements won’t be enough. The challenges involved in making renewable energy work at the scale and cost required by today’s data centers are considerable. That’s why a small group of data center operators are combining renewable energy generation technologies with hydrogen production and storage, allowing renewables to potentially capture a larger share of the power production market without major upgrades to the existing power grid.
The fuel cell solution
Hydrogen fuel cells lie at the heart of this strategy. These devices create energy through the electrochemical reaction between air and hydrogen. The electricity produced can be stored in batteries or used to drive an electric motor that powers a vehicle. Daimler and other automotive manufacturers, for example, have been successfully testing fuel cells in cars for many years.
The advantage of fuel cells over traditional fossil fuel-powered devices is they are sustainable and carbon-neutral—their only by-product is water. This means data centers no longer need to rely on diesel generators or other carbon-heavy backup power sources to cover any power gaps. And given that a fuel cell can keep running as long as there’s hydrogen to fuel it, there’s no limit on the amount of power generated—a constraint of traditional battery backups.
There have already been some early successes and a lot of interest from major vendors running experimental trials. For example, eBay has been running at least one of its data centers almost exclusively on fuel cells since 2013. And big IT players like Microsoft and Apple are currently deploying fuel cells experimentally, using solid oxide fuel cells (SOFC) that run on natural gas. None of these approaches are truly carbon-free, in that they use natural gas or biogas to create the fuel cell’s hydrogen, but they are a first step in getting fuel cells scaled up for production applications.
HPE—along with the National Renewable Energy Laboratory (NREL), Daimler, and Power Innovations—has gone a step further. The group is pioneering a truly carbon-free approach, using renewable energy to create hydrogen, the storage of hydrogen, and the use of hydrogen to power fuel cells that will eventually deliver energy to data centers.
The idea is to combine renewable energy with fuel cell technology. Essentially, renewable energy, such as wind and solar, powers the data center when in sufficient supply, and surplus power is directed to hydrogen electrolyzers that create hydrogen from water, which can then be saved. The stored hydrogen is fed back to fuel cells when renewable energy isn’t available (a backup option similar to a battery) to power the data center’s racks.
One big challenge is keeping these fuel cell-driven systems cool, as waste heat is a major by-product of a fuel cell’s chemical reaction process. To achieve this, HPE and its partners are using fuel cells that have proton exchange membranes to harvest waste heat and use it to drive adsorption chillers. These chillers produce 9°C water that is fed back into the data center for cooling the data center’s racks.
A faster payback
Waste heat recapture saves millions of dollars that would otherwise be spent keeping a data center cool, contributing to a faster payback period for this technology and lowering total cost of ownership for the carbon-free fuel cell solution. For the data center, there’s a significant decrease in operating expenditures (OpEx), because you can lower the ongoing costs of facility staff, maintenance, power, and cooling, which is typically among a data center’s largest recurring expenditures. And there are, of course, positive environmental externalities from going carbon-free.
On the capital expenditures (CapEx) side of the equation, a fuel cell technology solution is far cheaper than a traditional data center because 50 percent of the costs of building a data center are typically associated with the electric infrastructure buildout. With a fuel cell solution, you can remove the costs of adding generators, AC distribution, and wads of electrical cable. All these savings dramatically reduce the data center’s construction costs.
Generating electricity in proximity to the data centers that consume it increases efficiency and decreases the losses associated with the transportation of energy from a distant power plant. The higher energy density of hydrogen makes it an attractive substitute to the intermittency of renewable energy, and the widespread adoption of fuel cells to power data centers could also potentially advance their development as a cost-effective green energy source, with more widespread adoption potentially leading to increased development and lower cost. Using the fuel cell approach, and leveraging Daimler’s automotive fuel cells, HPE aims to drive energy generation costs below 20 cents per watt, the level at which fuel cell-powered data centers become viable without subsidies.
While the fuel cell project is primarily a proof of concept, we hope this innovation inspires our customers to consider new emerging technologies as part of the energy portfolio they use to power data centers—technologies that lie beyond traditional renewable sources, such as wind and solar. We are committed to exploring new disruptive technologies and advancing the IT industry toward the green data center of tomorrow.
This article/content was written by the individual writer identified and does not necessarily reflect the view of Hewlett Packard Enterprise Company.