Axion Power International, the developer of advanced lead-carbon batteries and energy storage systems, talked of ongoing work in the transportation sector at this week’s Agrion Global Network for Energy event.
Vani Dantam, senior vice president of business development, sales and marketing, was a featured speaker at the meeting in New York and covered the development of an electric hybrid 18-wheel truck powered by Axion batteries. Dantam also discussed Axion’s continuing work with Norfolk Southern on its first all-electric locomotive powered by Axion’s batteries, and the advantages of the batteries in stop-start applications.
Siemens is currently installing its first Sitras Energy Storage (SES) unit with supercapacitor technology in the US, on the TriMet Portland-Milwaukie Light Rail Transit Line.
The southeast Portland Tacoma substation location will house the first US storage unit that allows for energy created during braking to be stored and then re-used in one of two forms, energy savings or voltage stabilisation during peak demand times, says Siemens.
TriMet will use the system in voltage stabilisation mode to avoid problems that have led to disruptions in mass-transit operations. If a number of vehicles accelerate simultaneously, system voltage can drop below a critical level and result in instances of under-voltage tripping in vehicles and, consequently, disruptions in passenger service.
The SES ensures the system voltage always remains within the required range and voltage-related disruptions no longer occur.
A Portland, US, light rail system is to implement a braking-energy recuperation system using ultracapacitors produced by Maxwell Technologies and a USD$4.2 million grant from the US Department of Transportation’s Transit Investment for Greenhouse Gas and Energy Reduction (TIGGER) programme.
American Maglev Technology (AMT) is installing the system, which it also designed, on 27 light rail vehicles operated by the Portland, Oregon area’s Tri-County Metropolitan Transportation District.
AMT’s system captures and stores regenerative braking energy as it is generated then uses the stored energy for acceleration and releases surplus energy to other vehicles on the system as needed, thus helping to fulfill TIGGER’s remit of greenhouse gas reduction.
Gravity and rolling stock are the keys to Jim Kelly’s Advanced Rail Energy Storage concept. An electric motor powered by surplus electricity propels a train up a slope and when the electricity is required during periods of higher demand or low supply, the train is allowed to roll back downhill, turning the same motor, which now acts as a generator.
And like so many other energy storage concepts, the scale is big: in this case, eight miles long. This is the length of track planned for the Tehachapi mountains in California, which should be able to store up to 500MW of power.
The US already has one and now the UK is tinkering with the idea of making battery-operated trains, with the government publishing a study to say that the vehicles are a future possibility for the country, according to a report in The Guardian. The new breed of electric loco would run an intercity service of 600 miles on a single charge and be an alternative to diesel engines on those lines that are prohibitively expensive to electrify.
An eight metric tonne battery would power such a train using a super capacitor or flywheel for the varying power requirements of the route. The reason it probably won’t happen any time soon? Cost, of course… mainly because the battery alone which would set back the rail company GBP£150,000 per year in replacement costs.
Battery giant Saft has just announced that it has cut the ribbon on a new factory in Bidadi, Bangalore, with its partner Amalgamations. The factory, which will double Saft’s local capacity, will produce advanced rechargeable nickel batteries for industrial uses. Among these will be aircraft (Saft products are certified for use by the Indian Airforce), mobile telecoms and what the company describes as “mega power plants”.
Interestingly, one big factor spurring the factory opening is public rail transport. According to the company’s press office: “The Bangalore plant incorporates all the resources required to support the Indian operations of major railway OEMs: from design to manufacturing and commissioning of battery solutions.
“It positions Saft to benefit from the large investments in the Indian railway market, anticipated for at least the next five years.”
Saft batteries are already to be found in the rolling stock of India’s booming city metro systems and it is heartening to think that at least somewhere in the world it is public transport, not the private vehicle, that is stimulating energy storage growth.
It’s not just what you do, it’s the way you do it. That’s what researchers into lead acid batteries found, when they successfully designed a charging algorithm to overcome some of the aging processes that plague this type of energy storage unit.
The batteries in question are the one thousand individual cells powering Norfolk Southern Railway No. 999, the first all-electric, battery-powered locomotive in the United States. Like all acid-lead batteries, they suffer from a sulphation, a condition where lead sulphate builds up on the electrodes and, as an insulator, impedes cell performance. The Penn State University research team overcame it by a simple variation in charging rate for the battery.
The improvement of 30%, without the need for any physical or chemical changes in the batteries, is obviously good news for anyone wanting to promote the use of lead-acid energy storage in heavy applications such as this.