Solar Tech Solutions - Battery Storage

Understanding Solar Battery Storage

Solar battery storage systems work by storing excess electricity generated by solar panels during periods of high sunlight and making it available for use when sunlight is not available, such as during the night or on cloudy days.

Overall, solar battery storage systems enable greater energy independence, increased utilization of renewable energy, and improved resilience against power outages or grid disruptions by providing a reliable source of backup power.

Here's how it works:

Charging
During daylight hours when solar panels are producing electricity, any excess energy generated beyond immediate demand is used to charge the battery storage system. Depending on the type of system installed, the electricity may be converted from direct current (DC) to alternating current (AC) using an inverter, to make it compatible with the battery charging system.
Energy Storage
The charged battery stores the excess energy for later use. Most solar battery storage systems use lithium-ion or lithium iron phosphate battery chemistries, which are both efficient and have a high energy density. These batteries can store a significant amount of electricity in a compact form.
Discharging
When energy demand exceeds the electricity generated by solar panels, such as during the evening or when solar production is reduced due to weather conditions, the battery discharges stored energy to power the electrical appliances and devices in the home or facility. The inverter converts the stored DC electricity back into AC electricity for use in the building's electrical system.
Grid Interaction (if applicable)
In some cases, solar battery storage systems are also connected to the electrical grid. During periods of low energy demand or when the battery is fully charged, excess energy can be exported to the grid, allowing the system owner to earn credits or revenue through net metering or feed-in tariffs. Conversely, when the battery needs to be charged or when energy demand exceeds solar generation, electricity can be imported from the grid.
Monitoring & Control
Solar battery storage systems are typically equipped with monitoring and control systems that track energy production, consumption, and battery status in real-time. This allows users to optimize energy usage, manage energy costs, and ensure the reliable operation of the system.

What are the Benefits of Battery Storage?

Solar battery storage offers several benefits for homeowners and businesses looking to maximize the value of their solar energy systems.

Having solar battery storage enhances the benefits of solar PV energy systems by providing increased reliability, energy independence, cost savings, and environmental sustainability. It empowers users to take control of their energy usage and contribute to a more resilient and efficient energy infrastructure.

Here are some of the benefits:

Energy Independence
Solar battery storage allows users to store excess energy generated by solar panels during the day for use during periods when solar production is low or unavailable. This reduces reliance on the grid and increases self-sufficiency.
Optimise Energy Costs
By storing excess solar energy for later use, solar battery storage enables you to optimize your energy consumption patterns. You can maximize self-consumption of solar energy, reduce reliance on grid-purchased electricity during peak demand periods, and lower overall energy costs.
Backup Power
Solar battery storage systems can provide a reliable source of backup power in the event of grid outages or disruptions. This ensures continuity of essential electrical loads, such as lighting, refrigeration, and communication devices, during emergencies.
Time-of-Use Savings
If you have a tariff with time-of-use electricity pricing, such as Economy 7, having a solar battery storage system will allow you to store excess solar energy when electricity rates are low and discharge it when rates are high. This helps to offset higher electricity costs during peak hours and maximize savings on utility bills.
Environmental Benefits
Solar battery storage promotes the integration of renewable energy sources into the electricity grid, leading to reduced reliance on fossil fuels, lower greenhouse gas emissions, and reduced energy transmission losses. It contributes to a cleaner, more sustainable energy future.
Grid Stabilization
OK, so it's not a huge benefit for you persoanlly, or your business, but solar battery storage systems can help stabilize the electricity grid by reducing demand during peak periods. By storing excess solar energy and discharging it during times of high demand, you can help alleviate strain on the grid and reduce the need for costly infrastructure upgrades.

AC and DC Coupled Batteries

AC-coupled and DC-coupled batteries refer to different configurations for integrating battery storage with solar PV systems, each with its own set of advantages and considerations.

The choice between AC-coupled and DC-coupled batteries ultimately depends on factors such as system compatibility, installation requirements, efficiency considerations, and project goals.

Both configurations offer benefits for integrating battery storage with solar PV systems, and the optimal choice will vary depending on the specific needs and circumstances of each installation.

Below is an illustration of the differences bewteen the two set-ups:

AC-Coupled Batteries

In an AC-coupled configuration, the battery system is connected to the AC side of the solar PV system, typically after the solar panels' DC power has been converted to AC power by the solar inverter.
This setup allows for greater flexibility and compatibility with existing solar PV installations, as the battery can be added to systems with any type of inverter, including string inverters and microinverter.
AC-coupled batteries are often easier to retrofit into existing solar PV systems, making them a popular choice for homeowners and businesses looking to add energy storage to their existing solar installations.
However, AC-coupled systems may experience slightly lower overall efficiency due to additional conversion steps between DC and AC power.

DC-Coupled Batteries

In a DC-coupled configuration, the battery system is connected directly to the DC side of the solar PV system, typically between the solar panels and the solar PV inverter.
This setup allows for more efficient energy conversion, as the battery can capture DC power directly from the solar panels without the need for additional conversion steps.
DC-coupled batteries are often integrated into new solar PV installations or installed alongside DC-coupled solar PV inverters.
The output of solar panels is DC power and solar batteries are generally charged using DC power. Subsequently, DC-coupled systems offer slightly higher overall efficiency compared to AC-coupled systems, as there is no need to convert AC power to DC power; a process that inevitably results in some energy loss.
However, DC-coupled systems may be less flexible and more complex to install or retrofit compared to AC-coupled systems, as they require coordination between the solar PV inverter and the battery system.

What to Look for in a Solar Battery

Solar battery storage systems come in many shapes and sizes, each with different benefits and considerations.

When evaluating a solar battery system, several key attributes should be considered to ensure that it meets your energy storage needs effectively.

Here are some important factors to look out for:

Capacity (Energy Storage)
Capacity refers to the total amount of energy that the battery system can store, typically measured in kilowatt-hours (kWh). Higher capacity batteries can store more energy and provide longer backup periods during power outages or periods of low solar generation.
Charge/Discharge Power (Power Rating)
Charge/discharge power, often expressed in kilowatts (kW), indicates the maximum rate at which the battery can be charged or discharged. Higher power ratings enable faster charging/discharging and support the simultaneous operation of multiple high-power appliances.
Depth of Discharge
Depth of discharge refers to the percentage of the battery's total capacity that can be safely discharged before recharging is required. Batteries with a higher depth of discharge allow for more usable capacity and greater flexibility in energy management.
Cycle Life (Number of Cycles)
Cycle life represents the number of charge/discharge cycles a battery can undergo before its capacity degrades to a specified level (e.g., 80% of initial capacity). Longer cycle life batteries can sustain more charging/discharging cycles over their lifespan, resulting in greater durability and longevity.
Round-Trip Efficiency
Round-trip efficiency measures the energy efficiency of the battery system by comparing the amount of energy discharged from the battery to the amount of energy required to charge it back to full capacity. Higher round-trip efficiency indicates less energy loss during charging/discharging cycles.
Response Time
Response time refers to the speed at which the battery system can respond to changes in energy demand or supply. Faster response times enable rapid adjustment to fluctuating solar generation or sudden changes in load, improving overall system reliability and performance.
Compatibility
The battery storage system must be compatible with your existing or planned solar PV system. Consider factors such as voltage compatibility, communication protocols (e.g., Modbus, CAN bus), and integration with solar inverters and monitoring systems.
Warranty & Maintenance Requirements
Review the warranty terms offered by the battery manufacturer, including coverage duration, performance guarantees, and warranty conditions. Additionally, consider any maintenance requirements, such as regular inspections or battery management system updates.
Safety & Certification
Prioritize battery systems that meet industry safety standards and certifications, such as BS, EN, EN IEC, ISO and UL standards, and G98, G99 and G100 certifications.
Also, the battery storage system should be installed by a fully qualified Microgeneration Certification Scheme (MCS) certified installer and be commissioned by a NAPIT electrician to ensure all safety guidelines are met and any risks associated with battery storage systems are minimised.

BATTERY STORAGE

No more "use it or lose it"..

How It Works

Benefits

Battery Types

What to Look For