A 150kWh energy storage system using ultracapacitors and lithium-ion batteries to support grid stability in both residential and industrial settings has been deployed in Ireland.
The Tallaght Smart Grid Testbed uses a combination of Li-ion batteries, a Microgrid stabaliser and Maxwell Technologies’ ultracapacitors for active power support in the grid's distributed network.
The demonstration uses existing Maxwell modules containing 2.7V, 3000F cells to supply 50kW for 20 seconds.
The ultracapacitors will perform fast functions such as frequency response, while the batteries are used for peak shifting and operating reserve.
The system works in combination with German renewable energy systems developer and distributer Freqcon's Microgrid Stabilizer.
The batteries of the Stabilizer have a storage capacity of 150kWh and will addresses the electricity intermittency challenges that accompany high renewable energy penetration.
The Testbed, run by the South Dublin County Council and the Micro Electricity Generation Association (MEGA), will test how energy storage can minimise electricity distribution issues and grid instability.
It is one of many similar projects in Ireland as the country works toward its goal of 40 percent renewable energy generation by 2020.
With multiple sources of renewable energy generation, Ireland’s grid network has to cope with voltage and frequency issues before distributing the electricity to end users.
Dudley Stewart, secretary general of MEGA, said: "Smart grid projects are a priority in Ireland, and, depending on the local set-up, the grid challenges can vary greatly.
"Freqcon's Microgrid Stabilizer can be customized for individual projects, and the combination of batteries and Maxwell ultracapacitors is a promising solution.”
Dr. Franz Fink, president and CEO of Maxwell, said, "As the European Union, China, the United States and other countries around the world work toward their renewable energy consumption and generation targets, ensuring optimal renewable energy production will be critical.
“With a reduced number of fossil-fuel-based synchronous generators in operation, grid stability is becoming a challenge, and we expect ultracapacitors will play an important role in addressing this issue."
Unlike batteries, which produce and store energy by chemical reaction, ultracapacitors store energy in an electric field.
This electrostatic energy storage mechanism enables ultracapacitors to charge and discharge in fractions of a second, perform normally over a broad temperature range (-40 degrees Celsius to +65 degrees Celsius), operate reliably through a million or more charge/discharge cycles and resist shock and vibration.