Since Apple released its first unibody MacBook Pro, the company has promoted its environmentally friendly approach to product design. Most of the MacBook Pro is made from recyclable materials, such as aluminum and glass. The laptop's components are also "energy efficient and free of many harmful toxins" [source: Apple].
With Apple keeping a close eye on its environmental footprint, it makes sense that the company would consider renewable energy sources to power its products [source: Apple]. In December 2011, the U.S. Patent and Trademark Office published these two patent applications by Apple for a "portable and cost-effective fuel cell system" for its portable devices:
Both of these applications listed hydrogen as a potential fuel source. The documents also cited a provisional patent application titled "Portable Hydrogen Fuel Cell System" filed June 16, 2010, and listing the same inventors.
This news created buzz in the tech industry as 2011 drew to a close. A hydrogen fuel cell combines hydrogen (stored in the cell) and oxygen (from the surrounding air) to make water and electricity. According to Apple, hydrogen fuel cells "can potentially enable continued operation of portable electronic devices for days or even weeks without refueling" [source: USPTO].
Apple isn't the first company to pursue hydrogen fuel cells for powering devices. You can already buy charging devices for your existing electronics that use hydrogen fuel cells as a power source. For example, the Horizon MINIPAK is a pocket-sized charging device with a USB port. The device is powered with one of Horizon's Hydrostik fuel cells, a refillable cartridge of hydrogen that produces 1 Watt per hour of continuous power consumption, or the equivalent of 10 AA alkaline batteries [source: Horizon].
Apple's goal is to make a lighter, longer-lasting battery that's good for the environment. But will it be good for the user? Let's take a closer look at hydrogen fuel cells, Apple's design and the potential benefits and risks of using this technology in your laptop or smartphone.
Bringing Hydrogen Fuel Cells to Computers
Mobile computing has relied on rechargeable batteries for decades. Like non-rechargeable batteries, these rechargeable cells produce electricity through an electrochemical reaction inside the battery. The fuel cells within the batteries store the energy from an AC power source while they're plugged in by reversing that electrochemical reaction inside the battery. You can read more about what's going on inside the average battery in our article How Batteries Work.
As of this writing, Apple's portable devices products rely on lithium polymer batteries. These batteries use chemicals that rely on lithium ions moving within a polymer electrolyte to produce electricity. Unlike their lithium-ion predecessors, this polymer is an inorganic, nonflammable material. These batteries are notorious for not holding their charge very long and for using materials that require a lot of energy and chemical material to produce [source: EcoGeek.org].
Today, the electronics industry is looking to replace lithium polymer batteries with technology that has historically powered another well-known portable device: the automobile. For decades, scientists and engineers have researched hydrogen as an alternative fuel for cars [source: Wise].
For automobiles, hydrogen fuel cells are flat and thin so that they can be stacked together inside a single battery. Apple's patent applications reveal an effort to use that same fuel cell technology in a smaller package. Besides being scaled to fit within a computer, the hydrogen fuel cell would be lighter and more efficient than lithium polymer batteries.
More importantly, it would last much longer and produce no harmful waste that could pollute the environment.
What Apple isn't saying is what kind of hydrogen fuel cell we can expect. One of the barriers that the automobile industry has had with regards to hydrogen fuel cells is finding a reliable source of hydrogen. Most hydrogen gas produced today is obtained by processing fossil fuels, and the rest uses electrolysis which also requires existing energy. This creates a paradox: The hydrogen fuel cell is cleaner and more efficient, but it still relies on the non-renewable sources it's aiming to replace [source: Wise].
In its patent application, Apple offers some ideas for a rechargeable design that could perform a hydrolysis reaction to produce hydrogen during recharging. It proposes various chemicals to assist this process, though, which calls to question just how environmentally friendly these batteries could be. It's too early to tell whether Apple will run into the same hydrogen fuel cell paradox that the automotive industry did.
Supposing Apple jumps over the hurdle, what are the benefits and risks of having fuel cells in your MacBook or iPhone? Let's look at that next.
Benefits, Risks and Challenges in Hydrogen-powered Computing
Earlier, we discovered the benefits Apple hopes to bring to portable computing by developing hydrogen fuel cell batteries:
- Long-lasting power; more hours of use between charges
- Lighter; less impact on the weight of the device
- Produces a non-toxic byproduct
With the convenience of a longer charge, another benefit to hydrogen fuel cell batteries might be peace of mind. For example, a longer-lasting battery in your iPhone means less risk that the phone will shut down in middle of an important phone call. A lighter battery also means that Apple might enjoy the benefit of lower shipping costs for its products.
But what about the risks? Hydrogen has a reputation that dates back to before the infamous Hindenberg explosion. For portable electronics, the danger of hydrogen fuel cells isn't necessarily in using the hydrogen, but in storing it.
As of this writing, there are two common ways to store hydrogen: as a pressurized gas or as a cryogenically frozen liquid. The gas requires encasing the hydrogen in a way that prevents leaks or explosions when you jostle it. The liquid requires the additional weight of a cooling device, which could negate the benefits of a lighter fuel.
Fortunately, fuel cell designs are already overcoming these storage concerns. For instance, each Hydrostik, which we mentioned earlier as the power source for the Horizon Minipak, stores "a tiny amount of hydrogen as part of a solid metal complex and with very little pressure" [source: Horizon]. If Apple can implement a similar or better storage solution, it could produce hydrogen fuel cells that have as few, or perhaps even fewer, risks as its lithium polymer batteries.
If the risks are controlled, Apple's biggest challenge will be producing a reliable product at a reasonable price. The price of a hydrogen-powered iPhone or MacBook is affected by the price of production. Based on its patents, we can conclude the company's already putting a lot of time and resources into developing the technology. With that assumption, it's likely that Apple will also carefully consider the cost impact of that technology versus what its customers are willing to pay for it.
For lots more on the future of hydrogen powered portable devices, charge on over to the next page.
More Great Links
- Apple, Inc. "MacBook Pro and the environment." (Jan. 11, 2012) http://www.apple.com/macbookpro/environment.html
- Apple, Inc. "MacBook Pro Design." (Jan. 11, 2012) http://www.apple.com/macbookpro/design.html
- Apple, Inc. "The story behind Apple's environmental footprint." (Jan. 11, 2012) http://www.apple.com/environment/
- EcoGeek.org. "Lithium Polymer Batteries: A Review." TreeHugger. Discovery Communications LLC. Dec. 11, 2006. (Jan. 11, 2012) http://www.treehugger.com/gadgets/lithium-polymer-batteries-a-review.html
- Horizon Fuel Cell Technologies Pte. Ltd. "Introducing the MINIPAK Personal Power Center." (Jan. 11, 2012) http://www.horizonfuelcell.com/portable_power_minipak.htm
- Horizon Fuel Cell Technologies Pte. Ltd. "MINIPAK: Frequently Asked Questions." (Jan. 11, 2012) http://www.horizonfuelcell.com/files/MinipakFAQ.pdf
- Quick, Darren. "Apple files patents for hydrogen fuel cell technology to power mobile devices." Gizmag. Dec. 28, 2011. (Jan. 11, 2012) http://www.gizmag.com/apple-fuel-cell-system-patent-application/20958/
- Santilli, R.M. "Alarming Oxygen Depletion Caused by Hydrogen Combustion and Fuel Cells and their Resolution by Magnegas." Paper contributed to International Hydrogen Energy Forum, Sep. 11-15, 2000. Cornell University Library. (Jan. 11, 2012) http://arxiv.org/abs/physics/0009014v1
- Wise, Jeff. "The Truth About Hydrogen." Popular Mechanics. Hearst Communications, Inc. Nov. 1, 2006. (Jan. 11, 2012) http://www.popularmechanics.com/science/energy/next-generation/4199381