ZBB’s Project Manager, Mr. Christopher Kuhl said, "This project is a first of a kind trial in the United States to use energy storage as a dispatchable resource on the grid to make up for shorter duration changes in outputs from wind power. Creating effective operational models using resources like the ZESS POWR system will make wind energy a more knowable and valuable generation source."
Advanced Energy Storage Solutions.
The biggest problems facing power utilities worldwide are blackouts, brownouts and the huge capital investments required in upgrading the transmission and distribution networks to deliver the increasing demand for energy.
In the rapidly expanding renewable energy sector, solar panels and wind turbines are in desperate need for a technology to store energy and re-supply that power during high consumer peak times.
ZBB Energy Corporation – a leading innovator of energy storage systems – is breaking industry ground by providing turn-key energy storage systems to utility companies, industrial and commercial organizations and renewable energy generators for:
* Peak shaving / plant deferral/ asset optimization
* Renewable energy support
* Energy efficiency management
* Remote area power systems
* Mission critical power
Developing and producing products, which increase energy efficiency, minimize the impact on the environment and maximize the use of renewable energy is our brand promise.
The ZBB Zinc Energy Storage System (ZESS) is a proprietary and patented regenerative fuel cell based on zinc/bromide technology, which is very different in concept and design from more traditional methods of energy storage such as the lead/acid battery. The ZESS technology is based on the reaction between two commonly available chemicals, zinc and bromide. The ZESS consists of a zinc negative electrode and a bromide positive electrode separated by a microporous separator. An aqueous solution of zinc/bromide is circulated through the two compartments of the cell from two separate reservoirs. The electrolyte stream in contact with the positive electrode contains bromide which is maintained at the desired concentration by equilibrating with a bromide storage medium (Figure 1.). The bromide storage medium is immiscible with an aqueous solution containing zinc bromide. All battery components are made from a bromide inert plastic.
Unlike the lead acid and most other batteries, the ZESS uses electrodes that cannot and do not take part in the reactions but merely serve as substrates for the reactions. There is therefore no loss of performance, unlike most rechargeable batteries, from repeated cycling causing electrode material deterioration. During the charge cycle metallic zinc is plated from the electrolyte solution onto the negative electrode surfaces in the cell stacks. Bromide is then converted to Bromine at the positive electrode surface of the cell stack and is immediately stored as a safe chemically complexed organic phase in the electrolyte tank. When the ZESS discharges, the metallic zinc plated on the negative electrode dissolves in the electrolyte and is available to be plated again at the next charge cycle. In the fully discharged state the ZESS can be left indefinitely.
The ZESS offers 2 to 3 times the energy density (75 to 85 watt-hours per kilogram) with associated size and weight savings over present lead/acid batteries. The power characteristics of the ZESS can be modified, for selected applications. Therefore, the ZESS has operational capabilities which make it extremely useful as a multi-purpose energy storage option.
The ZESS technology is composed of a module or a series of modules for increased power. The ZESS 50 holds 50 kWh, which would roughly power a home for two days, and includes three cell stacks, each containing 60 cells. The module dimensions are 4’ x 4’ x 6.5’, weighing 3,200 pounds. The ZESS 500 fully charges in 4.5 hours and has continuous power of 250 kilowatts (kW), sustainable for two hours, with 200% peaking capability. The ZESS 500 holds 500 kWh, which is actually ten of the ZESS 50s strung together, and is used for commercial or utility applications. Exhibit 4 shows the ZESS 50 and ZESS 500. These storage devices can be located anywhere in ambient temperatures and transported to support the need of renewable energy to mitigate utility congestion. The “Turnkey” capabilities are beneficial based on the ease of simply plugging the batteries into the grid or other alternative source. Furthermore, these products are predominantly manufactured with recyclable plastics, allowing for low production costs and economical mass production.
The ZESS systems store energy from a number of sources and are highly compatible with global renewable energy markets: wind, solar, hydroelectric, biofuels, ocean power, and biomass. The ZESS 500 is easily transported on a 20-foot trailer and weighs approximately 30,000 pounds. The modular design aims to increase or decrease power needed by either adding or subtracting modules in the string, which is a valuable feature. Other products do not provide these transportable designs and modular capabilities for the added flexible benefits.
* Store and re-supply generated power during high demand periods
* Smooth power delivery from generator to the grid.
ZESS provides the necessary means to control intermittent renewable power generation and to optimize the energy utilization.
ZESS allows the PV technology to store energy when the sun is shining and provide power when sunlight is limited by cloud cover or during the night. The ZESS can be used to store power from the solar panels and shift the distribution of the power to align with the customers peak demand requirements (typically later in the day).
ZESS is designed with capabilities of connecting with wind turbines and either storing over-supplied energy or supplying stored energy as needed to smooth the intermittency of wind power generation. As penetration of wind energy increases on the utility grid, the intermittent nature will have negative impacts on the grid stability. Integrating ZESS minimizes the intermittent nature and allows wind generation to be more predictable and therefore a more valuable generation asset.
About ZBB Energy Corporation
ZBB Energy Corporation (NYSE AMEX: ZBB) provides clean energy storage solutions based on proprietary zinc rechargeable energy storage technology that addresses requirements in multiple markets such as alternative energy applications, large electrical utilities and green residential and commercial architecture. A developer and manufacturer of its modular, transportable and environmentally friendly Zinc Energy Storage Systems ("ZESS"), ZBB Energy was founded in 1998 and is headquartered in Wisconsin with offices also located in Perth, Western Australia. ZESS POWR is a ZBB registered trade mark.