by David Flint
Two weeks after Beacon Power celebrated the completion of their frequency regulation plant in Stephentown, a serious mishap has occurred that has people in town wondering. As Kevin Sweener was driving down Route 22 from Berlin on Wednesday evening, July 27, he saw a cloud of smoke coming from the direction of the Beacon Power plant. Turning onto Grange Hall Road he passed by the plant and determined that the smoke was definitely coming from there. Sweener called a member of the Stephentown Fire Department who relayed the call to 911. Word quickly spread around town that there had been an explosion at Beacon Power. The Stephentown Fire Department responded promptly.
Fire Chief Joseph Zwack said they received the call at 6:30 pm. Arriving on the scene they found a lot of dust and soot but no fire. Whatever happened it had enough force to blow the concrete cover at least partially off of one of the 200 flywheel units. He said the Fire Department did not enter the plant because the plant has its own suppression system in case of equipment failure. Zwack and Assistant Chief Rik McClave interviewed members of a maintenance crew from Beacon Power who arrived shortly afterward. They assured Zwack that the company would give the Department a full report as soon as staff has had time to assess the situation and determine the cause. One of the things Zwack will want to know is whether the appropriate alarms went off as they were designed to do.
Beacon Power Communications Director Gene Hunt said he had not yet had a chance to view the damage but believed it was a case of a single failed flywheel. The one megawatt pod in which that flywheel resides has been shut down temporarily, but the rest of the plant is continuing to run as normal. He said it should not be labeled an explosion and there was no fire. It was rather a matter of the flywheel coming unraveled. “It failed in the way it is designed to fail,” he said, “It grinds itself into dust.” It looks terrible but is not dangerous and the sooty material that gets spewed out is actually harmless carbon fiber dust from the unraveled flywheel, he added. An automatic suppression system, he said, acts to keep most of the dust down. There is no toxic material, he said, and the flywheels are well contained in their concrete housings.
Hunt could not say for sure why the concrete cover was partially blown off because vents in the cover are designed for a controlled release of the air pressure that would be generated by a disintegrating flywheel. Why that did not work exactly as designed, he said, is one of the things that a team already on site will be working to determine.
Paul Spresser says
Carbon dust is of the same degree of ignitability as coal dust. I would suggest the carbon dust may have reached a density of between 100 and 400 gram per cubic metre and some ignition source, either a spark of sufficient energy or a heat source of about 530 degrees celcius was available which may have caused an ignition.
Carbon dust IS a combustible dust. This fact should not be ignored.
mike says
At some point in time any device will fail, reasons of wear, tear, design flaws, or the product flaws within themselves when made, as well as the insulation of the parts and product. There could also be tampering with and many other possibles to achieve failure. The good of this though is the outcome of an actual failure in the field and not just one based on white paper. The failure may not represent similar or future failures but does give one the actual result of a failure and is nowhere near the seriousness of what could happen with different technological failure, whether it is a short term fire, toxicity, and or lasting environmental damage seen or unseen but knowing the products material composition and what happens to the composition in the event of a failure, and what it does to the surrounding enviroment,this type of technology,flywheels, may give one the security of safety over other types of green technology and any other advancements of energy conservation
tobyw says
What is the power storage capacity on one of these flywheels.
David Flint says
Tobyw:
Beacon Power rates their Gen4 flywheels at 100kw. In the Stephentown plant there are 20 “pods” connected to the grid, each pod having ten flywheels. So one pod has 1 megawatt of power storage capacity and the plant in total has 20 megawatts.
Charles R. Toca says
Power storage capacity is 15 minutes. So a 100kW flywheel would have 25kWh available. The 2OMW system has 5MWH. However, the flywheel application is frequency regulation, pulsing power up or absorbing power down, so they must operate around their center of charge – so only about 7 minutes of energy is available.
Chris says
I agree with mike. The S’town facility is a Beta site and issues will certainly arise due to the fact that these units are now running in a real working environemnt and not a lab environment. This is a great opportunity to resolve the issue so it is not widespread in future facilities.
Carson N. Powell says
It is a good thing that the company learns early on about their actual and potential maintenence requirements.
Carson N. Powell says
I am surprised that only one flywheel has failed out of 200 of them. At least they did not have to recall it from the customers.
Mike says
In response to the carbon dust theorey it should be mentioned that I read these pods are in a vaccum which would change all of the specs mentioned. In fact they are being considered for operation in space on satelites.
Shawn says
Carbon fiber dust is an inhalation hazard. You don’t want to breathe them in. It’s not asbestos level bad, but just think about fiberglass insulation. You should never work with that without a respirator, and carbon fiber dust should be treated the same.