A comprehensive collection of news and information about composites.
Posted by: Sara Black5. March 2014
Fiberglass composite waste piles up at Zajons, a German recycling facility.
An issue facing the composites industry right now is how to reuse and repurpose material, to avoid landfilling and to be able to label products as more environmentally “green.” Several companies have started up over the last decade to reclaim and reuse high-value carbon fiber, such as Materials Innovation Technologies (MIT, Fletcher, N.C., USA) and its spinoff company MIT-RCF (Lake City, S.C., USA), ELG Carbon Fibre Ltd. (Coseley, West Midlands, U.K.) and Adherent Technologies Inc. (Albuquerque, N.M., USA), among others. Carbon fiber’s relatively high cost makes such efforts profitable. Recycling of carbon composites has been embraced by The Boeing Co. and Airbus, among many others, to make their offerings more attractive, for one, and to develop reuse scenarios for composites that are as robust as those for aluminum, steel and other metals, which boast highly successful recycling percentages. (See our 2010 story, "Carbon fiber reclamation going commercial.")
But what about glass fiber and glass fiber products like mats? With glass fiber costing just a small fraction of carbon, recycling of glass isn’t as good a value proposition, although some companies, like Owens Corning (Toledo, Ohio, USA), are implementing programs such as fiberglass shingle recycling. In Europe, waste glass composites are being co-processed in cement kilns. CompositesWorld has been contacted on several occasions for help in finding a recycling option for either virgin or glass waste.
In one instance, the manager of a wind blade manufacturing plant in Gaspe, Quebec, Canada, was trying to meet his company’s ISO environmental standards, and had no place to send the waste dry fiber from blade layup. He asked (here’s a link to the original column, "The green challenge") for input from our readers on possible solutions. And just the other day, we got a call from a warehouse owner/operator who has some very large rolls of fiberglass mat or veil material that he wants to get rid of. We said we’d help, but so far have had zero luck in finding a use for what is likely several tons of virgin glass that will likely end up as solid waste.
So what is the answer? We’d like to hear from you on ways you’ve found to recycle glass fiber, either raw goods or cured parts. Are there entities out there that buy and sell used, old but reusable composite materials, like the large rolls of mat? Please let us know your thoughts in the comments section below.
Video of carbon fiber recycling R&D at the University of Nottingham (U.K.)
Posted by: Ginger Gardiner4. March 2014
Go-Ahead Group has outfitted six London buses with composite flywheels from Williams Hybrid Power, modified from reliable, performance systems used in Formula 1 racing.
SOURCE: (left) Go Ahead Group, plc and (right) Williams Hybrid Power.
Composites in Flywheels
Flywheels have been used for thousands of years (e.g., in pottery wheels) and are still used in piston engines today. The basic design of a flywheel is a disk that rotates, sometimes at very high speeds, using conservation of energy to store surges from a power system and then release that power back as needed.
In the 1950s and 60s, flywheels were used on buses in Switzerland, but they were heavy, prone to explosive failure and had no way of compensating for the angular momentum that made turning difficult. Composites have played a large part in solving these issues.
In the 1960s, Urenco (Buckinghamshire, U.K.) developed a flywheel that used composite materials to make the disk, or rotor, much lighter and replaced stationary magnets with a magnetically loaded composite (MLC) made from glass fiber impregnated with magnetic powder. (See “Composite Flywheel: HEV racing dynamo” in Dec 2011 CT). The MLC eliminates eddy current losses, boosting storage efficiency to 97 percent, while carbon fiber has significantly increased rotor tensile strength.
Energy Storage Systems Table by Ricardo plc
All-composite rotors — versus steel hub and composite overlay — offer lighter weight and reportedly improve safety. The lighter weight also improves energy storage, as POWERTHRU explains: “Kinetic energy is roughly equal to mass times velocity squared. So doubling mass doubles energy storage, but doubling the rotational speed quadruples energy storage.” Thus, today’s all-composite rotors allow faster rotational speed (40,000 to 60,000 rpm), which increases short-term energy storage capacity.
Composite construction has also helped ensure safety via optimized containment and rotor designs that are less prone to fail, but when they do, can be completely contained. Finally, gimbals are now used to counteract angular momentum effects. As the CT article describes, Urenco's composite flywheel technology was modified by the Williams Formula 1 motorsports team and then spun off as Williams Hybrid Power (WHP, Oxfordshire, U.K). Many other companies have also now entered the market.
Composite Flywheels in Use
There are two main forms of equipment: mobile systems for cars, trucks, construction equipment and light rail trams, and stationary units used to support mass transit rail systems and power grids.
For cars, trucks and construction equipment, the flywheel is typically coupled with a continuously variable transmission (CVT) or hybrid transmission by electrical cables. During braking, electricity is generated by an electric traction motor at the axles, which travels through the cables to charge the flywheel, spinning it up to 40,000 rpm or higher. Then, when the vehicle accelerates, the system works in reverse, so that less energy is needed from the combustion engine or from an electric/hybrid vehicle’s batteries. Energy/fuel savings can be as much as 40 percent, and CO2 emissions are also cut significantly. Thus, the more a vehicle stops and starts, the better its fuel efficiency, and, unlike a battery, a flywheel never loses its ability to charge and discharge energy.
For buses, WHP reports that a single flywheel, smaller than a spare tire, can reduce fuel costs by 15 to 40 percent, with an installation that is relatively easy and cost-effective. Flywheel bus programs and suppliers include:
Auto and Truck
Light Rail and Trams
These include lineside systems for mass transit rail networks and electrical grid support, the latter including power output smoothing for wind-diesel and other hybrid renewable energy-based systems. Flywheel energy storage devices reduce the amount of diesel fuel needed in hybrid systems when the wind or other renewable energy output falls. They also reduce charge-discharge cycles for batteries, enabling them to be used as long-term bulk storage, which is their strength. This prolongs battery life and improves the network’s transient response (i.e. decreases the number of seconds-long power outages) and fault-clearing capability (each power loss, or fault, must be cleared before power can be restored).
Mass Transit and Rail Lineside
The Williams F1/Advanced Engineering website has a great video showing how stationary flywheel systems work in this application. Williams claims energy savings of up to 30 percent are possible in a typical metro application and reduced voltage and power demands on the electrical network could enable more trains during peak demand as well as prevention of costly network upgrades or else downgrading network demands to meet same peak capacity. Other rail flywheel projects and suppliers:
Power Grid Support
According to WHP director Patrick Head, there are 500,000 composite centrifuge rotors (used for enriching uranium) that have been operating 24/7 for 20 years. (Note: a quick analysis of Urenco enrichment facilities estimates 575,000 centrifuges in operation by 2020.) According to an in-house strategy document, Urenco claims, “Another huge strength that Urenco has is their centrifuge technology that runs for 35 years while competitors have to replace their machines every 12 to 15 years.” Williams claims that initial investment costs for its stationary flywheel systems — which are capable of 7 to 10 million deep charge-discharge cycles — are much lower than competitive energy storage systems that have much shorter service lives, namely ultracapacitors (≈1 million cycles) and batteries (≈10,000 cycles).
In its December 2011 report, “An Assessment of Flywheel High Power Energy Storage Technology for Hybrid Vehicles,” Oak Ridge National Laboratory (ORNL, Oak Ridge, Tenn.) compares the performance of flywheels and batteries and concludes, “the most effective utilization of flywheels is in providing high power while . . . just enough energy storage to accomplish the power assist mission effectively. . . . flywheels could be effectively utilized in conjunction with and complementary to batteries . . . can extend the life of batteries by allowing their charge and discharge to be less demanding and can even allow the batteries to be downsized and made less expensive to purchase and maintain.”
The report “Advanced Energy Storage Systems Market by Technology . . . Global Trends & Forecast to 2018” by MarketsandMarkets.com — which includes flywheels as well as pumped hydro, compressed air, batteries and supercapacitors, and is also split by grid storage and transportation applications — estimates an annual growth in excess of 16 percent, from more than $4 billion in 2012 to nearly $10 billion by 2018. There are many other estimates that predict higher numbers. For example, battery supplier Eos Energy (New York, N.Y.) predicts a global opportunity of $16 billion by 2016 for batteries in electric vehicles alone. Other projections for power grid devices are in the $33 billion range.
An article by Paul Tullis on slate.com outlines six qualities that an ideal energy storage solution would have:
Flywheels actually deliver almost all of these, except for cost, which is still an issue. The table below shows projected cost figures given in the 2011 ORNL report with an additional line item for the Velkess flywheel, developed by Silicon Valley inventor, Bill Gray. He claims it can store electricity for $300,000/MWh, or what he says is about one-tenth the cost of comparable storage by Beacon Power. Gray says he reduced the cost of materials by using E-glass fiber instead of carbon fiber.
Interestingly, Boeing Research & Technology (Seattle, Wash., USA) showed a graph in a 2012 presentation targeting less than $100/kWh via a new proprietary fiber in the flywheel rotor material. Meanwhile, WHP’s Patrick Head says its materials cost $723.12 per unit and is targeting an annual production of 1,500 machines. However, it admits these small volumes keep unit cost high and for its next step in mass production a partner like GKN, Alstom or Siemens will be needed to achieve the necessary manufacturing efficiencies.
Will flywheels finally reach the tipping point? The market drivers for improved fuel efficiency, smart grids and more sustainable power networks are all supporting it, and the wave of players involved is mounting. Still, volume applications are needed. Perhaps if new lower cost composite rotors can indeed deliver performance and reliability, and manufacturing can be scaled sufficiently, flywheels will at last be able to deliver their energy potential en masse.
Other companies listed in the 2011 ORNL report:
Posted by: Jeff Sloan26. February 2014
Two recent and apparently unrelated news events in the composites industry may have long-term implications for the supply and demand of aerospace-grade carbon fiber and carbon fiber prepreg.
First, Boeing announced that it will build the carbon fiber composite wings for the 777X at it's massive assembly facility in Everett, Wash., USA. This was not too surprising as Boeing and the International Association of Machinists & Aerospace Workers (IAM) District 751 had just signed an eight-year contract extension that promised, in effect, to place 777X assembly work in the Seattle area. The only real question was where.
Second, the world's largest carbon fiber manufacturer, Toray (Tokyo, Japan), announced last week that it has purchased 400 acres of land in Spartanburg County, S.C., USA. The press release Toray issued regarding the acquisition was worded carefully to avoid stating outright that the property would be the home of a new carbon fiber manufacturing facility, but much of the text referenced carbon fiber and carbon fiber prepreg and the importance of those materials to Toray and the aerospace industry. Given that the 400 acres bought are just a few hours away from Boeing's Charleston, S.C., 787 final assembly line (FAL), it is probably not unfair to suppose that Toray will soon be expanding carbon fiber capacity there.
The question of the day is this: Whose carbon fiber will Boeing use to fabricate the 777X wings? Toray is the material of choice on the 787 Dreamliner. If one assumes that this connection will carry over to the 777X, then the next question is this: How will Toray supply all of the carbon fiber prepreg needed for the 787 and the 777X wings? Toray already announced in early February 2014 the expansion of its prepreg capacity in Tacoma, Wash., but this was for 787 demand only.
The 777X wings will demand either another expansion in Tacoma, or a shuffling of carbon fiber prepreg capacity between Tacoma and the anticipated new facility in South Carolina to make sure each Boeing facility is getting the material it needs.
On the other hand, companies like Toho Tenax (Rockwood, Tenn., USA) or Hexcel (Stamford, Conn., USA), which supplies much of the carbon fiber used on the Airbus A350 XWB, might win the 777X wing contract, which would introduce a host of new carbon fiber supply and demand questions and variables.
In any case, these are exciting times in aerospace composites, and it will be interesting to watch events unfold.
Posted by: Ginger Gardiner25. February 2014
Wal-Mart Stores, Inc. (Bentonville, Ark., USA), branded as Walmart, revealed its Walmart Advanced Vehicle Experience (WAVE) concept truck at its Sustainability Milestone Meeting last week. Much like the recent BladeGlider and ZEOD RC electric vehicle (EV) racecars, the WAVE’s front end design is not dictated by a block engine. With its hybrid diesel-electric powertrain fitting completely under the cab, the WAVE can take advantage of a more triangular, aerodynamic body shape. Though it obviously cannot achieve the amazingly low aerodynamic drag that enabled the original DeltaWing racecar to use half the fuel of its competitors at Le Mans and run twice the distance on a single set of tires, the WAVE is a bold step toward more fuel-efficient transports. WAVE partner Peterbilt Motors (Denton, Texas, USA) has already demonstrated that a Class 8 truck can average 10 mpg — versus today’s average of 5.5 to 6.5 mpg — via its SuperTruck.
Nissan BladeGlider (left) and ZEOD RC (right) electric race cars
and the DeltaWing racer that pioneered the triangular body at Le Mans (bottom).
The WAVE truck’s batteries and electric motor are coupled with a diesel microturbine by Capstone Turbine Corp. (Chatsworth, Calif., USA). Its C30 (30 kW) and C65 (65 kW) “range extender” turbogenerators — which can also use natural gas, biodiesel or aviation fuel (Avgas) — fire up after EV batteries reach a set stage of discharge, recharging the batteries and extending driving range up to 500 miles, depending on the type and size of vehicle.
Walmart claims it is the largest private fleet in the U.S.
And then comes the carbon fiber. Walmart says the WAVE’s trailer, built by Great Dane Trailers (Chicago, Ill., USA), “is made almost exclusively with carbon fiber, saving around 4,000 pounds [1814 kg], which can then be used to carry more freight.” It also claims that this is the first time carbon fiber has been used to fabricate a trailer and also the first time 53-ft (16m) continuous composite trailer panels have been made in one piece. (Note: Glass fiber composite trailers were discussed in the February 2003 CT article, “New Lightweight Trailer Delivers Heavy-duty Performance”).
Walmart set a goal in 2005 to double the efficiency of its truck fleet by 2015. According to www.walmartgreenroom.com, the company made significant progress by 2011, increasing efficiency by 69 percent through reduced packaging material and size, improved volume utilization and better route management, enabling delivery of 65 million more cases while driving 28 million fewer miles. During 2010, this eliminated 41 million miles of driving, saving $75 million. The company has added 13,000 skirted trailers (see “Commercial trucking: Streamlining the Big Box” in June 2013 CT) and its efficiency gains equate to avoiding almost 41,000 metric tons of CO2 emissions, the rough equivalent of taking 7,900 cars off the road.
In constant pursuit of its efficiency goal, Walmart has built a variety of prototype tractors including the technologies highlighted below, aiming for an average fuel consumption of 10 mpg or more. While it evaluates its latest WAVE fleet efficiency program prototype, Walmart announced it will buy 2,000 hydrogen-fueled forklift trucks for use in its U.S. and Canadian distribution centers.
Hybrid assist: Tractors using a traditional diesel drivetrain with an electric motor to recover energy normally lost during braking. The hybrid also provides additional torque in high-load situations like climbing hills. Onboard batteries power heating, air conditioning and the electrical system when the engine is off. This first hybrid tractor built by Peterbilt and Eaton Corp. (Cleveland, Ohio, USA) showed promise, but the batteries need improvement in cost, size, weight and capacity in order to achieve an acceptable return on investment (ROI).
Wheel-end hybrid assist: Similar to the hybrid assist, this model built with Freightliner features two wheel-end electric motors on the second axle, placing energy precisely where it is needed and avoids energy loss from the front of the tractor. However, recharge of the hybrid battery has been an issue due to the motor placement.
Full propulsion hybrid: This dual-mode hybrid, built by Meritor (Troy, Mich.), runs completely on its electric motor at speeds up to 48 mph, switching to its diesel engine above that threshold. The next generation is already in development with an enhanced battery system and improved robustness.
Natural gas: For the past three years, Walmart has been testing five liquid natural gas trucks — made by Westport (Vancouver, BC, Canada) in California. It is also testing a Westport/Cummins Alpha 12-liter natural gas engine. Though the company continues to evaluate potential savings and efficiency gains with natural gas, its challenges include lack of fueling infrastructure.
Posted by: Sara Black20. February 2014
Comptek and Aero Solutions developed a composites-based telecom tower
repair system that helps operators extend tower life.
More than 100,000 cell phone towers dot the American landscape. No one wants one in their back yard, yet millions depend on their electromagnetic signals that are essential to modern communication. The "not in my back yard" (NIMBY) attitude means that as these structures age, operators can’t easily erect new towers, and must make repairs to extend their service life — and add capacity for the proliferating equipment of more and more providers.
Developing safe repair methods took ingenuity. The galvanized steel towers support miles of flammable coaxial cables, and when workers weld steel jackets or additional structural support high onto the existing structure, welding sparks and slag have often ignited cables, resulting in expensive fires. Plus, scaling the towers for any reason is very hazardous, even deadly; many climbers have died in tower accidents.
Structural engineer Jim Lockwood, CEO of Comptek Structural Composites (Boulder, Colo., USA) knew there was a better way: “A telecommunications company saw an article I had written for the American Composites Manufacturers Assn. Market Development Alliance [now the Composites Growth Initiative], and contacted me. That was our opportunity to introduce composites for the tower repair market.” Twelve years later, Comptek and its spinoff design/build company Aero Solutions LLC, have the corner on this specialized and successful market.
Comptek and Aero Solutions have tackled some daunting telecom tower repair challenges that could not have been accomplished without composite materials. A good example is the repair of the 175-ft/54m tall KHON television broadcasting tower, atop a 42-story high-rise building in downtown Honolulu, Hawaii, USA. The tower was so badly corroded and deteriorated that Honolulu officials condemned it. Yet, without it, the television station would have had to find an alternate and less desirable location, since building codes prevented construction of a replacement.
Aero Solutions designed a carbon wrap for the tower, with unidirectional carbon fiber, aligned parallel to the tower axis, carefully bonded to the steel, followed by outer hoop wraps of unidirectional carbon fiber over 40 percent of the tower, to ensure structural integrity. A cement-based grout injection followed, to provide additional stiffness to the monopole. Materials and grout pumping equipment had to be delivered by helicopter. Once stabilized, the tower was wrapped with Comptek’s water-activated polyurethane prepreg as an outer weather-tight layer, supplemented by a confining peel ply during prepreg cure (shown in blue). Lockwood says “Composites delivered a miracle in that situation — there simply was no other alternative.”
Look for a longer, more detailed report on this repair technology in the April 2014 issue of Composites Technology magazine.