Energy Efficiency – The New Killer App

Laura Peters, Lead Technical Editor -- Semiconductor International, 7/19/2007

Look in any newspaper, any airport sign or around SEMICON West 2007 and you’ll see that the focus of future technologies is on energy efficiency. From solar cells to fuel cells, alternative energies are needed to offset the high price of fossil fuels, and portable electronics are demanding longer battery life and cleaner, more environmentally friendly solutions. Here are some of these significant trends.

Vroom, vroom?

There is nothing quieter than an all-fuel-cell car. Will that lack of an internal combustion engine leave consumers feeling a need for more power or, at least, the sound they normally associate with a powerful engine? Of course, it is not the sound that is inhibiting adoption of fuel cell cars. It has to do with the need to refuel the hydrogen in a convenient way. Meanwhile, hybrid vehicles are gaining in popularity, while the standard vehicles are being made more efficient. This creates very real competition between a more efficient, lighter standard vehicle (without the heavy battery) and the hybrid car, which gets much better gas mileage, but typically costs a few thousand dollars more. However, the fuel cell car remains a long-term goal because of its complete lack of harmful emissions. If you want to see what these cars look like up close and in person, check out the fuel cell automotive display in the Emerging Technologies & Markets TechXPOT at SEMICON West, hosted by the California Fuel Cell Partnership. Along the lines of transportation, also check out the sailboat that uses carbon nanotubes (CNTs) to achieve a 30% improvement in stiffness and strength on the masts.

Getting back to fuel cells, the market is not restricted to automobiles. Fuel cells for laptop computers hold promise as well. Besides methanol-based fuel cells, hydrogen, sodium hydrate and even various metal hydrate-based fuel cells are being looked at by the major manufacturers of laptops and cell phones. The main issues are heat generation associated with fuel cells and the larger footprint than that of existing lithium ion batteries. And, as longer-lasting lithium ion batteries are made, the promise of a 10-hour fuel cell battery seems less enticing. In the end, fuel cell batteries are likely to complement existing PC, PDA and cell phone batteries.

1. The Chevy Volt, a fuel cell concept car, features a range of 300 miles. (Source: GM)

Solar cells

When future generations look back, they may see the passing of the RoHS legislation as one of the first major environmental actions that affected the electronics industry, but in many respects, we are seeing “greening” activity across the board. The most obvious is the strong focus on alternative energy sources and the numerous startup companies worldwide focused on photovoltaics and fuel cell manufacturing. It just so happens that the manufacture of these products can tap many of the same processing tools and materials used in device manufacturing. By serving these markets in addition to semiconductors, equipment and materials suppliers hope to build their portfolios and possibly enjoy higher growth rates than the typical 8-10% that is expected in the coming years for the semiconductor industry.

The photovoltaics industry now achieves the efficiencies needed for mass production (>15%) of solar panels at a reasonable cost of implementation. While the majority of installations are of the monocrystalline silicon type (>85%), thin-film epi and polycrystalline silicon approaches are rapidly catching up in terms of efficiency and fill factor (see "The Potential of Thin-Film Crystalline Silicon Solar Cells"), and promise a more flexible design and lower cost. Because half of the cost of today’s panels goes toward silicon, epi designs using less costly substrates may win out in the long run.

2. Silicon wafer-based solar cells (shown) dominate the commercial solar cell market, although thin-film-based photovoltaic cells can be manufactured at a lower cost, representing a promising market contender. (Source: S.A.G. Solarstrom AG)

Power usage

The focus on power consumption is also strong — especially when it comes to conserving power on server farms. The Green Grid is a recently formed global consortium dedicated to advancing energy efficiency in data centers and computing ecosystems. Members include the founders (AMD, APC, Dell, Hewlett-Packard, IBM, Intel, Microsoft, Rackable Systems, SprayCool, Sun Microsystems and Vmware) as well as recently added members (1E, 365 Main, Active Power, Affiniti, Aperture, Azul Systems, BT plc, Brocade Communications, Chatsworth Products Inc., Cherokee International, Cisco, ColdWatt Inc., Copan Systems, Digital Realty Trust, Eaton, Force10 Networks, Juniper Networks, Netezza, Novell, Pillar Data Systems, Panduit Corp., QLogic, Rackspace Managed Hosting, SGI, SatCon Stationary Power Systems, Texas Instruments, The 451 Group and Vossel Solution).