Meridian Lithium Battery Energy Storage System
Meridian lithium battery energy storage systems are designed for indoor residential use. Available in 24 volt or 48 volt configurations, ranging in storage capacity of up to 16 kWhr, Meridian system can be connected in parallel to increase storage capacity. System includes Balqon proprietary battery management system which monitors, reports, analyzes and protects the lithium cells from over charge or over discharge conditions. Custom configurations where systems can be connected in series for high voltage applications are also available upon request.
Indoor residential energy storage system up to 48 volts
Indoor energy storage systems are available in various configurations available in 24 or 48 volt configurations. All systems include Balqon proprietary battery management system which monitors each cell voltage, temperature and protects the cells from over discharge or over charge conditions. System storage capacity ranges from 8 kWhr to 36 kWhr and work seamlessly with any charge controller or inverter with adjustable voltage settings.
Outdoor residential energy storage system up to 96 volts
Outdoor energy storage systems include high capacity lithium batteries in NEMA enclosures available in 48, 72 and 96 volts and energy storage capacity of up to 120 kWhr. Equipped with CAN Bus control system, these storage units are equipped to be connected in series or parallel to customize your storage needs. Outdoor products include multiple control outputs for charge controllers and inverters and state of charge indicator.
Outdoor commercial energy storage system up to 700 volts
Commercial storage systems are ideal for large commercial and industrial facilities for peak shaving applications. Systems are customized for voltages ranging from 300 volts to 700 volts and storage capacity of up to 500 kWhr. Equipped with CAN Bus controls monitoring lithium cells up to 1000 amp hours with automatic cell balancing automatic emergency disconnects, contactor controls with optional high voltage charger.
Battery Storage, the most cost efficient technology for residential markets
Renewable energy such as wind and solar generates power intermittently with highly variable output reducing the viability of renewable energy as a reliable energy source. Ability to store this energy during peak production is a key to mass adoption of renewable energy in residential and commercial applications. Transition from a traditional fossil fuel powered centralized grid to a more decentralized, high efficiency renewable energy micro grid relies on the economics and reliability of the storage solutions.
During the past decade solar energy production has soared globally and is one of the fastest growing source of energy in residential and commercial markets. The industry has experienced a significant improvement in reliability of solar panels, charge controller and inverters during the past decade making adoption of renewable energy feasible on a large scale. The key factor for adoption now relies on the economics and availability of this power during peak periods of usage. The lower cost of production advantage of a centralized grid is offset by over 40% transmission loss during transfer of power from the generating plant to point of use. Meanwhile the advantage of generating power using renewable sources such as solar at point of use is offset by the disadvantage of intermittent production.
Incorporation of storage systems that can capture energy from renewable sources during peak production periods and use of the stored energy during peak periods of use is the key to the success of decentralized point of use energy production system. Technologies ranging from mechanical storage, hydro storage, air storage and battery storage are available in the marketplace to provide reliable solution to efficiently store energy generated by renewable sources. Although each storage technology has its advantages based on size of storage and application needs, battery storage is the most low tech, lowest capital investment solution for small renewable energy production sources in residential and small commercial plants and buildings.
Transfer efficiency effect on Solar
Balqon energy storage systems use lithium iron phosphate battery cells with yttrium which is a key rare earth metal that improves safety and performance in high temperature applications. When compared to lead acid batteries lithium batteries have a high transfer efficiency regardless of the pack voltage. Lithium batteries have a higher transfer efficiency of over 96% throughout the total voltage spectrum, which results in storing higher watts of energy produced by solar panels.
In lead acid batteries the transfer efficiency varies based on the voltage. When a lead acid cell is empty (below 80% depth of discharge) transfer efficiency is advertised at over 90%, yet the transfer efficiency can reduce to 55% when cells are almost fully charged. As an example, in a 1000 watt solar panel installation only 550 watts would be stored if the batteries are over 80% charged, under similar state of charge conditions 960 watts would be stored with a Balqon energy storage system leading to higher savings and improved return on investments for solar installations.
How to size battery energy storage system
The basic building block of lithium iron phosphate battery is a 3.25 V cell. Our energy storage system is a collection of 3.25 V cells connected in series that supply DC power to the inverter, which then produces 110 /230 VAC power that can be used to run household appliances. The decision to select 12/24/48 V battery bank is determined by the solar panels and by the specifications of the inverter.
In order to determine the size of the energy storage system:
1. Calculate average daily usage from your monthly utility bill expressed in kWhr. [DU]
2. Determine calendar days of backup energy storage needed in case of power outage [BD
3. Calculate: DU x BD = Energy Storage estimate [ESE] in kWhrs
4. Calculate: ESE x 1.25 = Energy Storage Capacity Actual [ECA]. As a general rule ECA of the lithium energy storage system should be 1.25 times [lithium batteries can be discharged to 80% of its nominal capacity, unlike lead acid batteries that can only be discharged to 50% of its nominal capacity] the ESE value expressed in kWhrs.
5. Select battery voltage of the storage system based on max voltage of PV system and inverter input voltage. [REV] defined in DC volts.
6. Calculate: ESE /REV = AHR [amp hour rating of each cell]
As an example, if the monthly electric utility bill shows consumption of 600 kWh, with an average daily consumption of 600/30 days = 20 kWhr [DU]. The decision to have minimum of one day backup power [BD]will require 20 kWhr X 1 X 1.25 = 25 kWhr [ECA] (25,000 watt Hrs) of energy storage. If the voltage determined by the solar panel array is 48 V [REV]than the size of the lithium batteries in amp hour capacity will be 25,000/48 = 520 ahrs.[AHR]
Benefits of Lithium Energy Storage in Grid Applications
Deployment of renewable energy technologies harnessing wind and solar energy to reduce the carbon footprint of our utility grid poses challenges due to the variable nature of grid operation. As energy production by renewable sources increase the unreliable oversupply of these sources result in curtailment of these renewable sources. Unless technologies are implemented that can provide greater flexibility to balance power supply with power demand the benefits of renewable energy production maybe offset by curtailment of the grid. The solution to optimize the benefits of renewable energy may lie in implementation of large-scale lithium battery energy storage systems.
To accommodate variable sources of electricity, grid operators may deploy load-balancing technologies that increase grid flexibility. These technologies will include improved forecasting of renewable energy production, building excess generation capacity, battery energy storage and demand side management. Variable sources of energy such as wind and solar are curtailed during periods of oversupply leading to strong market disincentives for renewable energy sources. Consequently, electricity produced from renewable sources is squandered resulting in lost revenues from renewable energy sources. Lithium batteries due to their high transfer efficiency, cycle life and depth of discharge have the highest potential to efficiently store variable sources of energy during peak production. Although storage technologies such as Compressed Air Energy Storage (CAES) and Pumped Hydroelectric Storage (PHS) provide a significantly higher cycle life over battery storage, the benefits of such technologies can only be realized in large scale installations. Lithium battery storage provides ability to scale and deploy much smaller storage systems cost-effectively allowing deployment of decentralized micro-grids at source of energy consumption.
The coincidence of peak energy production by renewable resources with power demand are especially prevalent in regions like Southwest United States where high solar insolation and large afternoon power demands due to air-conditioning reduces curtailment in the energy production. However grid flexibility and energy storage are essential for success of wind energy due to imbalances in peak production hours versus peak demand hours. While there are many reasons why battery storage provides useful tool for increasing grid flexibility, it is equally important to consider other benefits provided by battery storage, including improved power quality and access to electricity at times of generation shortages or grid failures.