Composite construction refers to any structure with two or more distinct materials that are combined to create an engineered product with properties “greater that the sum of its parts.”
Most people recognize fiberglass — fiber reinforced plastic (FRP) with E-glass as the reinforcing fiber — as the most common form of composite construction. Higher strength composites utilize carbon fiber as a reinforcement. Composite construction has developed primarily to support recreational boats, although construction and aerospace applications are now ubiquitous.
The engineering expertise, experienced labor force and established material supply chains for construction of large composite structures in the U.S. is well suited for development of renewable energy structures. Today’s challenging economic landscape provides an opportunity to diversify our recreational and industrial composites industry for renewable energy applications.
The global composite products market reached US $56 billion in 2007 according to Sean Lofgren of Lucintel. Data from the American Composites Manufacturing Association (ACMA) suggests that the U.S. has about a 30% market share. U.S. composite manufacturers employ 125,000 people and impacted suppliers and manufacturers employ another 338,000. In 2006, the U.S. manufactured over 4 billion pounds of composite structures. Although different market segments have gone up and down over the years, composites recently have seen more growth than aluminum or milled steel products. However, the current economic downturn has hurt the construction and marine industries severely.
The U.S. is responsible for building some of the largest composite structures in the world. Goodrich reports that they build surface sonar domes that weigh more than 20,000 lbs (submarine domes can weigh upwards of 40,000 pounds) and their facility in Jacksonville, FL has built composite structures weighing more than 100,000 lbs.
For comparison purposes, DIAB reports that a 50-meter wind turbine blade weighs about 40,000 lbs. As an example of U.S. composites manufacturing capability, Christensen Yachts has plans to build a 186-foot motor yacht in a new facility in Tennessee. The size, structural demands and complexity of composite structures built in the U.S. has positioned us well to undertake the construction of large structures envisioned for renewable energy devices.
Wind turbine blades are ideally suited for composite construction, as lightweight, complex airfoil shapes can be produced from molds with minimal labor input. Indeed, engineering and manufacturing processes for producing composite wind turbine blades is quite mature. However, the challenges of producing larger blades (and mass producing smaller ones) leaves room for development of improved design and manufacturing as we learn from systems that have already been fielded.
The greater opportunity for established U.S. composites fabricators may rest with newer renewable energy concepts that are now on the drawing board or in the prototype stage. This is especially true for Ocean Renewable Energy projects.
The economic viability of composite construction increases with the number of units produced, where the cost of design development and tooling can be amortized. For large renewable energy devices, the reduced weight of composite components when compared to metallic construction can greatly reduce transportation and erection costs. Perhaps the biggest advantage of composites for large energy projects is reduced maintenance costs over an expected 20-30 year service life. For large, unmanned engineered structures, corrosion resistance will be paramount for long-term economic viability.
So the stars are aligned for us. We have an emerging market that will need large, engineered structures that can withstand environmental degradation. The U.S. has a leading-edge composites fabrication capability with a diminishing demand for the products they produce. However, composites fabricators operate in a very competitive environment that leaves little room for internal R&D that would facilitate a smooth transition to the energy industry.
The Path Forward
The U.S. has an established composites manufacturing capability that leads the world in terms of innovation and productivity. However, the demand for composites (marine and construction) has recently been on the decline, leaving us with excess manufacturing capacity. The renewable energy industry is relatively new in this country, with many novel concepts still at their design or prototype stage. Wind turbine blade technology has been developed in Europe so for the most part, these two industries have not come together in the U.S., which is required if we are to become a world leader in renewable energy technology.
Some modest investment in R&D and market development now can reap huge returns in the immediate future. Unfortunately, the uncertainty surrounding renewable energy profitability and lack of a long-term, national energy strategy has hamstrung private-equity investment. The following initiatives are proposed to put us on the path to energy independence and create green jobs from an ailing composites industry:
The composites industry needs to develop an accurate assessment of current U.S. composites manufacturing capabilities that can support the renewable energy market.
Engineers and managers with knowledge of the composites industry should meet with renewable energy companies and present technical and business data to support the use of composite structures.
The U.S. is a world leader in transitioning technology from universities and government labs to the marketplace. However, a government entity is required to coordinate regional consortia to ensure funded efforts are aligned with national energy and economic goals.
Big companies with internal R&D funds gravitate to large projects with guaranteed payback though economies of scale. The Defense Advanced Research Projects Agency (DARPA) has provided a successful model of how to fund innovative companies and “long-shot” technology concepts with huge payback potential. Seed money should be provided to small, innovative renewable energy companies based on the DARPA model. Government support should not have a “matching funds” requirement, as this tends to rule out high risk concepts and small businesses.
By focusing a small amount of government funding capital (and more importantly, our world-leading innovative “human capital”) to align the composites and renewable energy industries, we can create a win-win situation for the American consumer and the American worker.
Erik Greene received his S.B. in Naval Architecture and Marine Engineering, Massachusetts Institute of Technology in 1979 and founded Eric Greene Associates Inc. in 1987 to serve the high technology engineering requirements of the marine industry. He specializes in the area of composite material structural design, manufacturing and training. An avid sailor, he has written for Professional BoatBuilder and Composites Fabricator magazines and is a regular presenter at Composites conferences. An expanded version of this article, résumé for Mr. Greene and copies of published articles and the book MARINE COMPOSITES are available for download at www.EricGreeeneAssociates.com.