Flywheel Energy FAQ

Q: What is the rating of the unit?
A: The useable stored energy is 2100 KW-Seconds. The nominal rating is 140KW for 15 seconds. Units can be operated in parallel for larger loads (higher KW) or extended time.

Q: I normally operate at 60% load, how much back-up time do I have?
A: Operating the unit at lower loads will extend the back-up time. The graph below illustrates the Load vs. Back-up time characteristic. The graph can also be used to estimate back-up times when units are paralleled.

Q: Does the product need external AC power?
A: Yes, it needs AC power from the output of the UPS for the fans, controllers and vacuum pump.

Q: What happens if the external AC power is lost?
A: There is a critical power supply that keeps the rotor assembly fully suspended; all other components are powered off --- fans, PC panel, vacuum pump, etc.

Q: What happens when you reach burst speed? There is a piece of steel rotating at high speeds. Do you have containment?
A: Vycon's flywheel rotor is comprised of Aerospace high strength materials that are controlled and processed per very stringent Vycon specifications. Through thorough design, analysis, testing, inspection, and qualification, Vycon ensures that the flywheel rotor will not burst.
Under normal operating conditions, the flywheel operates well below the predicted burst speed of the flywheel hub material. At 100% speed, the flywheel rotates at 36,000 rpm while the predicted burst speed of the flywheel rotor is 56,000 rpm. During the development stage, a flywheel rotor was rotated above 50,000 rpm and did not burst as rotordynamic instability at this speed prevented the flywheel rotor from going further up in speed.

Q: How expensive is the unit?
A: Flywheels typically costs 2-4X the initial cost of batteries, but considering batteries last only 3-5 years and batteries require significant maintenance, the flywheel solution is a much more attractive solution over the life of the UPS.

Q: Does the unit need to be bolted down?
A: Yes, each unit ships with the hardware necessary.

Q: Can the unit be installed in a (Seismic) Zone 4 environment?
A: Yes, we plan to have it evaluated and have OSHPD certified.

Q: Can the unit be installed on a raised floor?
A: Yes, a floorstand may be used to accommodate the unit.

Q: What safety, EMI and other agency certifications do you intend to have?
A: We are now in the final stages of UL and C_UL for safety. We also intend to market the product in Europe, so we will be pursuing CE, in which case EMI evaluation will take place.

Q: Is a vacuum pump necessary?
A: Our flywheel requires a vacuum pump. We use either an Alcatel or a Pfeiffer pump that are both very high quality. The vacuum pump does require the oil to be changed annually to keep it in good working condition.

Q: What is High/low cycle?
A: High/Low cycle refers to the specific use of the product. High cycle applications are where the product is cycled often, multiple times per day. An example of this would be in rail applications for voltage support and energy recovery at rail substations where the product cycles whenever a train arrives or departs (possibly a cycle every two to three minutes). 

Low cycle applications would be your typical UPS application, where the product goes through less than 100 full discharges per year. The unit may experience frequent short discharges, but infrequent full discharges.

Q: Is VYCON’s product a complete UPS solution?
A: No, the output of our Flywheel product is DC only. We do not provide the AC conversion, a UPS is required.

However, because 98% of fatal power quality events last less than 15 seconds, the Vycon product can completely replace battery banks when used in conjuction with a standby generator and prevent short cycling of the genset. If longer backup time is required without a genset, the Vycon system can cover 98% of the power quality events, thereby saving the batteries for the longer term events (battery hardening). This setup will prolong the life of the batteries and more easily provide high short event surge currents. For some applications, 98% coverage is sufficent and do not require a genset or battery banks.