Energy

Written by Thom Powell, AIA LEED AP

The 2030 Challenge offers a timeline for creating buildings that produce as much energy as they use – “net zero energy”.  As we begin to contemplate the conclusion of the year 2009, we are about to arrive at the initial benchmark of 2010.  This is the point where we are able to achieve a 60% reduction over 1990 levels of energy consumption for newly constructed buildings.  Per the 2030 Challenge, the first 50% could be achieved through energy efficiency.  Presumably, the next 10% will come from alternative energy sources, either localized, centralized or through a form of renewal energy certificates.  So, it is natural for one to ask where we are in the development of alternative energy resources here in Dallas, in Texas and in the United States, in general.  

 

SOLAR ENERGY

As recently as September 2008, the Department of Energy (DOE) announced investment into Solar Photovoltaic Technology Development to support President Bush’s Solar America Initiative and its goal to make solar energy cost-competitive with conventional forms of electricity by the year 2015.  The popular belief is that with current administration, we should be able to see this goal reached prior to the 2015 timeframe.  Investment by the DOE rewarded the following companies for their research into cost-effective photovoltaic (PV) technology.

1366 TECHNOLOGIES
1366 Technologies (Lexington, MA) – is developing new cell architecture and related processes for low-cost multi-crystalline silicon cells.  This project is expected to enhance cell performance by light-trapping texturing and grooves for self-aligned metallization fingers. By improving the light trapping and charge carrier movement within the cell, this project will significantly increase the efficiency of multi-crystalline cells. By the end of the project, 1366 Technologies plans to deliver a 19 percent efficient, 15.6x15.6 cm2, multi-crystalline silicon cell with a technology that is applicable across the crystalline silicon cell industry.

INNOVALIGHT
Innovalight (Sunnyvale, Calif.) is developing very high-efficiency, low-cost solar cells and modules by ink-jet printing their proprietary “silicon ink” onto thin-crystalline silicon wafers. The company’s contact-less printing process has been demonstrated to significantly reduce both the manufacturing costs and the complexity required to make today’s highly-efficient cells and modules.

SKYLINE BAR
Skyline Solar (Mountain View, Calif.) has developed an integrated lightweight, single-axis tracked system that has been demonstrated to reflect and concentrate sunlight over 10X onto silicon cells. The use of mirrors to concentrate light will reduce the use of the greatest cost driver for traditional silicon modules, the solar cells, by over 90%. Additionally, the design leverages the mainstream PV industrial base and amplifies its capacity through significant concentration to enable rapid scaling. It seeks to dramatically lower the cost to manufacture modules and install complete systems to achieve a levelized cost of energy below grid parity. By the end of this project, Skyline plans to deliver modules that exceed 12 m2 area and 15 percent aperture-area efficiency.

SOLASTA
Solasta (Newton, Mass.) is using a novel cell design based on an amorphous-silicon “nanocoax” structure, which increases current and lowers materials cost by shortening the path charge carriers must travel to the cell’s conducting wires. This approach effectively decouples the optical and electronic pathways. If successful, Solasta will deliver 15 percent efficient, 100-cm2 pre-production cells at the end of the project.

SOLEXEL
Solexel (Milpitas, Calif.) plans to commercialize a disruptive, 3D, high efficiency mono-crystalline silicon cell technology, while dramatically reducing manufacturing cost per watt. Through a series of novel yet low cost processing steps, this project will manufacture a solar cell architecture, which efficiently traps light using minimal material. At the end of this project, Solexel plans to deliver a 17-19 percent efficient, 156x156 mm2, single-crystal cell that consumes substantially lower silicon per watt than conventionally sliced wafers. Solexel aspires to be a gigawatt-scale PV producer within five years.

SPIRE SEMICONDUCTOR
Spire Semiconductor (Hudson, N.H.) plans on opening up the design space for three-junction tandem solar cells by growing differentiated bi-facial cells on a Gallium Arsenide substrate. This approach will allow spire to better optimize the optical properties of their device layers to better match the solar spectrum. Spire Semiconductor is targeting cell efficiencies over 42 percent using a low-cost manufacturing method.  

In February 2009, 1366 Technologies reported that the grant from the DOE was finalized.  In fact, 1366 Technologies hopes to show within 18 months that it can churn out 6-inch-square PV cells fast enough to build a 3-megawatt solar plant, as the National Renewable Energy Laboratory (NREL) award requires. “That forces you to automate critical parts of the process,” says 1366 Technologies president and CEO Frank van Mierlo. “You can have innovative cell architecture and produce it in the lab with tiny cells that are 1-by-1 inch, and show that the physics works. But by the time you do a 3-megawatt plant, you have to have truly solved all the scaling problems and have a handle on the true economics. That’s what the DOE program is about.”

The 1366 Technologies report is indicative of the timeframe required for the development of cost-effective solar PV energy resources.  If successful, 1366 Technology will be able to demonstrate an economical process for PV cell production by late 2010.  The NREL grant will oversee the process along the way and 1366 Technologies will have to perform about 20 or 30 intermediate milestones to complete the research process.   

WIND ENERGY

The Texas State Energy Conservation Office (SECO) monitors wind energy production within the state.  They report that for the past two years, Texas has been the top wind producer in the United States, with over 3,953 wind-generated megawatts (MW) installed. Texas is also the first state to achieve the milestone of one Gigawatt of wind installations in a single year (2007). Texas widened its lead over states by installing almost 2,700 megawatts of wind power last year.

Only two countries in the world installed that much wind in 2008. In fact, if Texas were a country—an idea never entirely out of fashion in the Lone Star state—it would rank 6th in the world in wind power capacity. The demand for additional wind power has grown so rapidly that the Texas electric transmission grid has a critical need for expansion.  In July 2007, the Texas Public Utility Commission announced its approval for additional transmission lines that could deliver as much as 25,000 megawatts of wind energy from remote areas in the state to urban centers by 2012, depending on how many wind farms are built. New transmission infrastructure will allow all Texans to access the state's vast wind resources.

DOE's Energy Information Administration (EIA) reports that wind power is the fastest growing renewable energy technology, growing by 45% in 2006 due to strong demand, investment of private capital, and the support of federal and state governments. Electric utilities have shown an increased interest in wind project ownership, and wind industry sales to power marketers have become more common. Wind power has consistently remained at or below the average price of conventional electricity such as coal, nuclear, and natural gas.

American Wind Energy Association (AWEA), the industry’s trade group, has determined that two-thirds of the predicted growth of wind energy generation in the U.S. will occur in Texas, as three of the five largest wind farms in the nation are located in Texas. Texas already holds the record for the world's largest wind farm, Horse Hollow Wind Energy Center, which was completed by FPL Energy, Inc. in late 2006. It also is the site for the nation's second-largest wind farm, the 504.8-megawatt Sweetwater wind project, the fourth phase of which attained commercial operation in May, 2007.

“There is plenty of wind out there and plenty of energy to be tapped. It's just like an oil field that doesn't run out.”  Tom Gray, AWEA

The Horse Hollow Wind Energy Center in Texas remains the largest wind farm in the world with a total capacity of 735 megawatts (MW) spread across approximately 47,000 acres in Taylor and Nolan counties near Abilene in west central Texas.  The wind plant consists of 291 1.5-MW wind turbines from General Electric and 130 2.3-MW wind turbines from Siemens.

One MW is enough electricity to serve 250 to 300 homes on average each day.

“Sound economic principles are driving wind energy development in Texas. The fact that wind energy is clean, reliable and inexhaustible is icing on the cake.”  Jerry Patterson, Texas General Land Office Commissioner

Despite the slowdown this year in the wind industry, the U.S. is still ahead of schedule to generate 20% of its electricity from wind by 2020, according to a new report by the AWEA.  Wind power has thrived because Texas is wide-open—both geographically and politically. There are plenty of open spaces to put wind farms and few barriers to building them.
Texas has optimal conditions for both wind and solar power.  With the continuing development in wind power and solar technology, alternative energy resources should continue to be on the rise for the foreseeable future.