Building energy management systems (BEMS) provide a highly adaptive solution for the ongoing refinement of building energy management. These systems use several emerging technologies for the remote monitoring of building energy performance and precision control of consumption.

In this article, we explain what building energy management systems are, how they work, and the benefits and limitations of implementing this technology in residential and commercial buildings.

What is a building energy management system?

Building energy management systems, or BEMS, are a diverse group of technologies that monitor and control the energy consumption of a building. They combine automation, the Internet of Things (IoT), machine learning, and artificial intelligence (AI) to precisely manage energy use by building appliances, lighting, and HVAC.

BEMS are distinct from building management systems (BMS) which are computer-based systems that integrate the functions of an entire building including, fire protection and security. BEMS are available as custom, programmable, or pre-programmed solutions.

Building energy management systems provide buildings and facilities managers with a tool for improving the energy efficiency of the properties they manage.

The IT systems that run BEMS gather data from a range of control and automation inputs. The following are example data sources used to optimize the use of energy with building-wide automated and manual improvements:

• traditional control and automation systems
• thermostats
• smart meters
• consumption data
• advanced sensors
• utility price tracking
• wholesale energy prices
• business intelligence

How do building energy management systems work?

BEMS are a type of building automation system (BAS) that monitors and controls the individual mechanical devices and appliances that consume energy in the building.

A competent BEMS requires: 

• A distributed network of sensors for parameters like temperature, light, humidity, and movement.
• Automated or remotely controlled actuators for pumps, vents, windows, radiator valves, thermostats, power switches, and light switches.
• A controller that receives inputs from the sensors and coordinates output instructions to actuators. The controller may be automated or a building manager can control it in real time.

The system uses its sensors and actuators to control and optimize conditions within the building, adapting to the use and demand of its occupants. For example, a BEMS can actively maintain a comfortable internal temperature by switching furnaces on or off, closing windows or adjusting radiator valves.

However, BEMS are distinct from standard thermostat-based heating control as it is much more hierarchical and delivers precision control that is integrated with other energy consumption.

Description of building energy management systems

The functionality of building energy management systems spans four key areas:

1. Visualization and reporting

Building energy management systems provide facilities managers with a software interface, for interacting with the system. The software element of a BEMS presents detailed reporting on the status and consumption of the building’s appliances and heating. Information relating to the BEMS is visually displayed, using dashboarding, charts, and graphs.

2. Fault detection and diagnostics (FDD)

Fault detection and diagnostics is a critical aspect of the management of buildings involving the identification of errors in the physical systems that operate in the building. By uncovering these faults and errors promptly, managers can remedy them before there is a derangement of energy resources, a change in building conditions, or failure of the system.

3. Predictive maintenance

Predictive maintenance uses IoT sensors and other condition monitoring tools to monitor the building energy systems. This technology can alert managers when maintenance is needed. By monitoring the performance of the energy systems and appliances in the building BEMS can ensure that appliances are properly maintained so they don’t use excessive energy.

4. Continuous improvement

A BEMS uses its data feeds and sensor input to look for opportunities to improve energy efficiency. The software algorithms and machine learning of the BEMS determine the parameters for implementing improvements to the building’s energy consumption, optimizing its performance.

Any building can be a smart building

BEMS can be implemented in any type of building including residential housing blocks, commercial buildings like supermarkets, offices, malls, or industrial sites where the BAS microprocessor technology was first used in the 1970s.

Factors to consider before installing a BEMS

The energy consumption needs of different buildings vary widely. This means that the specifications and functionality of BEMS have to be tailored to an individual building’s needs.

Here are some of the key factors that can help you determine the best type of BEMS for a building:

Building size

Building size is one of the most important factors for determining what caliber of BEMS is required. Large buildings, understandably, have greater energy demands than small residential dwellings. 

For a larger building, rather than using consumer ‘smart home’ solutions and billing analysis, building owners and managers build custom BEMS that include features like advanced and predictive analytics, demand response, building optimization and automated building controls.

Building location

The region the building is located contributes climatic factors that affect the energy demands of the building. In places where there is strong seasonality or temperature extremes, a BEMS can learn and manage consumption for the external temperature highs and lows to maintain a comfortable and consistent internal environment.

The number of buildings that need to be managed

It is hard to implement a harmonized BEMS for multiple buildings. Even identical buildings often have unique characteristics and performance nuances, making the implementation of a single BEMS difficult. This means that each building within an estate will require its own BEMS.

Building use

The building’s use determines the level and pattern of occupancy. The system that is used has to respond to the type of occupant, for example, office workers versus residents. BEMS specifically monitor and support occupant comfort, especially if they make adjustments to thermostats or air conditioning.

The benefits of building energy management systems

Building energy management systems herald a new age of smart buildings that managers can optimize for maximum energy efficiency, with equipment and appliances carefully controlled. These energy management systems deliver wide-ranging benefits to building owners, facilities managers, contractors, and building occupants.

Here are some of the benefits BEMS deliver:

1. Building energy management systems deliver excellent ROI

Property owners and developers who invest in BEMS benefit from their in-built energy and cost-saving functionality. These systems continually work to reduce peak power consumption and optimize the energy efficiency of the building by adapting to actual occupancy and demand. Savings in utility costs quickly offset the capital expense of installing the system.

BEMS that offer the highest level of customization to the building use and energy requirements give building owners and managers the most control. The more sophisticated the BEMS, the greater the control of energy consumption and potential energy savings it can achieve.

2. A BEMS enables the energy consumption of a building to be controlled

The energy data and diagnostic tools of BEMS can optimize a building’s energy use and curb wastage. Building energy management systems monitor patterns in the demand and usage of energy in a building for precision control of energy consumption. According to Honeywell Building Technology, a BEMS can deliver control of up to 84% of building energy consumption.

3. BEMS reduces energy costs

The continuous improvement and optimization that BEMS minimizes energy wastage, saving money on utilities. A BEMS can achieve energy cost savings of up to 55%, because of the level of fine control the system delivers. These savings have a positive impact on the operating costs of the building or facility.

4. BEMS conserve energy

BEMS are one of the most effective ways for buildings to conserve energy. The potential for energy savings are noteworthy, especially when up to 80% of energy consumption is for heating and hot water in residential and commercial buildings.

Improved energy management provided by a BEMS can offset thermal losses from older buildings. The active monitoring and control of a BEMS means that energy use matches occupant requirements and habits.

5. BEMS can integrate renewable energy solutions

The responsiveness of BEMS enables them to integrate renewable energy sources like solar energy, which do not give continual power. Developers can readily integrate solar energy management systems with the software platforms of the leading BEMS solutions to ensure that any renewable energy generated by the building is utilized for maximum cost savings or profit, if added to the grid.

BEMS can also integrate demand-response (DR) solutions that enable building operators to take advantage of renewables to manage and reduce their demand for peak hours electricity from the grid. Many BEMS software programs provide the interfaces for in-depth renewable energy integrations like DR.

6. BEMS are designed to be adaptable

The machine learning and artificial intelligence technologies that the leading BEMS use enable them to adapt a building’s energy consumption to the needs of the building occupants. These systems respond to changes in occupancy, seasons, appliance, and device consumption and integrating new systems and products to maintain optimized energy management at all times.

7. Can aid building compliance

Energy management of buildings is a political issue and many governments are producing regulatory guidance or legislation for improving the energy efficiency of properties.

As a type of energy management system (EnMS), BEMS can help a building obtain key certifications like the U.S. National Energy Performance Rating System and ENERGY STAR Building Certification Program or ISO 50001 that specifically deal with energy management.

8. BEMS use time-saving automation

BEMS are integrated with a variety of automation technologies to reduce the physical workload of running a building. Aside from running HVAC, a BEMS can oversee lighting, windows and invent integrated fire protection and access control. This reduces the human resources required for building maintenance and management.

9. Building energy management systems help to reduce greenhouse gas emissions

Building energy management systems control the consumption of all energy sources used by the building, including electricity, natural gas, and heating oil. These systems can switch to energy sources that do not directly release CO₂ like electricity rather than fossil fuels. By optimizing consumption the International Energy Agency suggests that there is an annual abatement of 1 GtCO₂.

10. BEMS prolongs the longevity of HVAC equipment and appliances

BEMS facilitate better management optimization and maintenance of HVAC equipment, prolonging its usable life. Because the use of HVAC is more precisely controlled, preventing the overwork of parts like fans and pumps that can rest as much as possible.

This keeps resources in use for as long as possible without the expense of premature replacement.

11. Building energy management systems can reduce maintenance requirements

Equipment maintenance is expensive and requires manpower. A BEMS can help reduce the need for routine and unexpected maintenance by remotely monitoring the performance of HVAC equipment, alerting building managers when their function becomes abnormal, or breaches a critical number of usage hours, for timely repairs.

12. BEMS safeguard business continuity

Corporate, industrial and healthcare facilities that cannot afford to have downtime can benefit from robust energy management that may even have to include backup sources of power. The close monitoring of energy sources and power systems by a BEMS means managers can detect and remedy problem before a critical incident causes downtime.

Facilities managers can program BEMS software with alerts for specific problems that they can receive remotely. Developers can also configure BEMS to support the Service Level Agreement (SLA) of companies like web hosts or cloud computing service providers.

13. BEMS can improve the comfort of building users or residents

BEMS facilitate environmental conditions within the building that keep its users or residents comfortable. They can accommodate individuals changing heating or cooling settings, or the use of devices that use more power. These adaptive systems are always learning how to best manage user demand to optimize the well-being of building occupants.

Limitations of building energy management systems

Like many technologies, BEMS have their limitations, which need to be understood to implement building energy management that delivers results. This technology has been embraced in many parts of the world and sensor-based IoT technology is becoming more and more accessible. However, this technology is still relatively nascent and may not always be able to achieve the building intelligence that is envisioned.

Here are some notable disadvantages of BEMS technology:

1. Data inputs can be extremely dense

The sheer volume of data that is generated by the distributed IoT sensors and other inputs can be too unwieldy to extract and visualize effectively. The software that processes and analyses this data must be sophisticated enough to use it in a ‘smart’ way, changing how energy is consumed.

2. Setting up a building energy management system is expensive

Significant capital investment is necessary to install the data acquisition infrastructure and to implement specific solutions for key areas of energy consumption such as lighting. Costs for a BEMS can range between $2.50 and $7 per square foot, with the IoT equipment, (particularly custom actuators), being a major expenditure.

3. Skilled labor may be required to analyze BEMS data

Building energy management systems require skilled building managers or building engineers who can analyze and act on the data that a BEMS collects and processes.

These professionals understand the software and can adjust configurations and set points to optimize consumption. However, this skill set is beyond an ordinary facilities manager role and commands a higher salary.

4. If the configuration is poor, a BEMS may not deliver value

BEMS technology delivers energy and cost savings through its advanced configuration. Even with the best data collection infrastructure, a BEMS will not deliver value without being correctly configured; set points and schedules so that it can implement any required optimizations.

The configuration of BEMS requires specialist contractors, who can optimize a poorly deployed and configured BEMS to improve savings. Buildings and businesses like hotels, stadia, or malls that have a wide range in occupancy benefit from the skilled configuration that can learn trends and take advantage of periods of reduced demand.

5. Energy management in a building may already be well optimized

Some buildings may already be extremely energy efficient with consistent schedules and performance that makes a BEMS redundant. Some offices and residential apartments have such consistent schedules and occupancy rates that their energy management is almost completely optimized already and BEMS will add few changes.

6. BEMS may miss energy consumption from small equipment and appliances

BEMS software tracks patterning in energy consumption, rather than the use of individual devices. These systems can miss small equipment like electronics because their load may not be large enough to trigger sensors.

Also, BEMS may not control smaller equipment that may be part of the building infrastructure as it is configured to focus on the building systems that impact operating expenses most.

7. BEMS malfunctions may impact occupant comfort

An obvious problem can arise if the BEMS activates the settings for winter during the summer months and vice versa. If the BEMS functions separately to the general building monitoring, problems like fan and lift breakdowns may be missed. This is why building managers desire highly integrated solutions that give them oversight of condition in the entire building.

8. BEMS are difficult to scale across multiple properties

BEMS cannot be used to run multiple buildings within a property portfolio. Each building requires its own BEMS infrastructure, data protocol, processes and integrations, according to its amenities, appliances, and building conditions. Coordinating multiple sites on a single BEMS would soon become unwieldy and few software vendors offer this service.

9. A building can maintain energy management certifications without a BEMS

Building owners and managers can get energy certifications like the ISO 50001 for building without the expense of installing a BEMS. Facilities managers can implement the best practices for energy management outlined in many certifications by using low or even no-cost initiatives. A BEMS can then be introduced further down the line once the building has realized the initial energy savings.

10. Building energy management systems carry an inherent cybersecurity risk

By using cloud-computing software to manage the energy consumption of a building, owners introduce the real risk that someone may hack their BEMS. The data generated by the BEMS is valuable and may expose the building occupants to risks if accessed by malicious agents. An attack on the BEMS may also lead to downtime of essential services within a building.

In conclusion

BEMS can impact the energy consumption and ongoing maintenance of a wide range of building types. When installed and configured properly, they can help building and facilities managers optimize the energy performance of a property while providing a comfortable environment for building occupants.

However, the lack of scalability, scope, and high costs still hamper the widespread adoption of this technology. Smart buildings are definitely the future but BEMS still need work to play a part in the next phase of energy management.

When trying to solar charge batteries, it is essential first to understand the several steps involved and the essential components that must also be there for the charging process to occur.

Main Stages Involved in Charging a Solar Battery

Here are the four main stages involved in solar battery charging basics that one needs to comprehend when charging batteries using solar energy:

1. The Bulk phase (first stage)

The bulk phase is primarily the initial stage of charging a battery using solar energy. This first stage starts when the sun shines or when the generator is turned on.

The bulk phase will initiate when the battery reaches a low-charge stage, and that is usually when the charge is below 80%.

In this stage, the solar panel puts into the cell as much amperage as possible. The voltage in the batteries rises gradually as they absorb the electricity.

See Related: DIY Solar Generator Guide

2. Absorb Stage (second stage)

The second stage of battery charging is known as the absorb stage. This stage is achieved when the batteries reach a charge of 14.4 to 14.8 volts or when the charge level is between 80 to 90% full.

Primarily, when the batteries reach this charge percentage, it enters into the absorb stage which also depends on the charge rate.

The above charge rate is basically for lead-acid batteries. The second stage halts as soon as the number of amps entering the batteries reaches a certain number that is pre-set or the programmed time elapses.

3. The Float stage (third stage)

The third stage comes immediately after the absorb stage. This stage is initiated when the charge controller lowers the voltage to a specific pre-set value. The float stage is achieved when the batteries reach a charge level of 100%. It is essential for you to know how to program your controller well.

4. The Equalization stage (fourth stage)

The final stage or the Equalization stage is a controlled overcharge stage which is done periodically.

The process of charging batteries using solar energy or the photovoltaic is different from using the mains power and needs to be approached differently. The difference occurs since the initial energy from the sun is not always available, or it comes in fewer amounts than the required.

The low costs of photovoltaic solar modules and its increasing efficiency are increasing the demand for this kind of renewable energy.

Components to a Solar Charging System

Some of the vital components of a solar charging system include:

1. Solar Panels

One of the essential components of the solar charging system is the solar panel. A solar panel is a device that is designed to absorb sunlight to generate electricity or heating power. It is the component that helps collect energy from direct sunlight and then converts it into electricity.

There are several types of solar panels. The three most common types are Monocrystalline cells, polycrystalline cells and amorphous or thin-film solar cell. It is essential to understand the basic features including the watts, cost and space you require before you decide the one to pick.

Here is help on how to build your own solar system.

2. Solar Charge Controller

The solar power generated by the solar panel is received by the solar charge controller. A solar charge controller is a component that helps manage the power that is going into the battery store from the solar panel.

It safeguards the deep cycle batteries from being overcharged during the day. It also ensures that power does not go back towards the solar panels overnight which can drain the batteries.

Solar charge controllers’ primary function is to manage power, but it may offer additional capabilities including load control and lighting. Thus, when the solar charge controller receives the solar supply, it then regulates the electricity and current directed to the batteries to ensure proper battery charging occurs.

A quality photovoltaic charge controller must have the pre-defined charge modes suit for each type of battery including flooded lead acid or AGM. It is vital to ensure that the input current and maximum voltage ratings are higher than the output of the solar array feeding it when selecting a solar charge controller.

There are numerous charge controller options to choose from including professionally configured solar panel or the charge controller kits that can help ensure that your components will work well together.

When charging batteries with solar energy, one should use a controller when the rated amperage of the solar panel is above 1% of the battery capacity. It is essentially the rule of the thumb for this procedure.

There are two main types of controllers in the market which include on/off and Pulse Width Module (PWM).

The On/off controller switches the power from solar panel off when the voltage of the battery reaches a preset level. It also turns it on when the voltage drops.

PWM controller is different as it allows the voltage to continually rise and then maintain it at a level that is high but steady.

3. Power Inverter

Another vital element is the power inverter. A power inverter is an electrical apparatus that helps convert direct current (DC) to alternating current (AC).

It is not part of the solar charging system but a primary add-on element that changes 12 v DC power to 120 v AC to power AC components and channels in your RV.

4. 12 Volt Battery Bank

The battery acts as a storage bank for the power generated from the solar panels. The cells can either be 12 v or 6 v deep cycle batteries provided that the output is 12 volts.

5. Battery Monitoring System

Another optional piece of equipment is the battery monitoring system. The battery monitoring system monitors functions involving battery voltage measurement, load activity and charge status.

It also controls the charging and discharging processes of the battery to prevent it from over-charging or under-charging to increase its shelf life.

6. Wiring

Copper wiring is another crucial element. Be sure to have copper wires with different thicknesses that help you connect the solar panels, batteries, charge controller, and an inverter.

7. Cutoff Switches

Cutoff switches are connected between various components to disconnect the elements for safety and maintenance reasons effortlessly.

8. Fuses

The last but not the least components are high amperage fuses of between 100 Amp and 250 Amp. The fuses are required to prevent electrical faults and component damage and are usually placed between the battery and the inverter connections.

Now you know how a solar system works to charge a battery

Solar battery charging basics are essential to anyone using solar energy system to help them understand how to use a solar panel to charge a battery. I hope this article has offered you valuable solar battery charging basics insights.

What do you think of our solar battery charging basics and instructions? Please let us know if you found our definition helpful.

In a rush? We think the Vmaxtanks VMAXSLR125 AGM 12V is the best option for most people.

If you are not connected to the utility grid, you need somewhere to store your energy. Having reliable solar batteries will help you save the electricity your solar panels produce during the day.

If you are connected to the utility grid, the batteries will save enough energy to cushion you when shortages in the grid occur.

Being able to identify the best batteries for solar will help you make the right choice whether your solar system is for your RV, your cabin or tiny house or any other setup where you will rely on stored power.

TOP PICK

Vmaxtanks VMAXSLR125 12V Rechargeable Deep Cycle Battery

The Vmaxtanks is an excellent battery for storing solar power for your tiny house, camper or home solar system.

Check latest price at Amazon

The 7 Best Solar Batteries in 2025

Here are some of the best batteries for solar you can choose from in the market. For those living completely off-grid, several brands will suit your solar battery storage needs.

1. Best Overall – VMAXTANKS 12-Volt 125Ah AGM Deep Cycle Battery

With the numerous products bombarding the solar battery market, this is our first choice for an off-grid solar system.

The battery is a deep cycle absorbed glass mat (AGM) battery that ranks among the best solar batteries in the market. It is among the most used deep cycle batteries in the solar storage industry.

With a Float Service lifespan of between 8 to 10 years, this heavy-duty AGM battery offers other numerous features like:

• 12V 125Ah AGM Deep Battery
• Military grade tailor-made plates and an 8mm Hex Screw in Terminals
• Built with 99% recombination capabilities and doesn’t emit any dangerous fumes or gases
• For bulk orders that exceed $150, Bargainshore will offer a Free Signature Confirmation
• The battery is ideal for cold weather, which guarantees your power even at minimal sunlight.
• 8 to 10 years of maintenance-free period

2. Renogy Deep Cycle AGM Battery 12 Volt 100Ah for RV by Renogy

The Renogy Deep Cycle AGM 12 Volt is another excellent solar battery you can use for your system. Although this type of solar battery is bulky and may take a significant amount of space, it is excellent solar energy storage.

Renogy Deep Cycle AGM is easy to install and doesn’t require much knowledge to get it operational.

This type of solar battery doesn’t require any maintenance, and therefore, it needs no monitoring.

Some of the things you should check when using this battery include:

• These batteries should not be deep charged, mainly when they are in series connections
• Always charge the solar batteries with suggested voltages
• The recharge capacity ought to be 1.1 ~ 1.5 * of the discharge capacity
• The batteries are best suited for solar marine, as well as off-grid applications

3. Best Budget – ExpertPower 12v 33Ah Rechargeable Deep Cycle Battery

The 4-stars rated deep cycle battery is an excellent choice for solar battery storage. Most people prefer this product due to its vast benefits.

With the ExpertPower 12V 33Ah battery, you will enjoy the following benefits:

• The battery utilizes the AGM (Absorbed Glass Mat) (AGM) technology
• Wide temperature range
• Genuine ExpertPower Battery – the product trusted mainly by users, and it is among the products with the highest reviews on Amazon.
• User-Friendly – the product has a smooth and one-time installation
• Operational temperature-discharge of between -40 °C to +60 °C and a recharge temperature of between -20°C to +50 °C
• Battery type – It is a 12V 33Ah deep cycle sealed lead-acid battery that has screw in terminals of 7.72(L), 5.16(W), and 6.34(H). Total height is 7.09 inch.

This product is one of the most popular batteries for solar power systems.

4. Battle Born LiFePO4 100Ah 12v Deep Cycle Battery –

LiFePO4 12V is a lithium-ion battery that is safe, strong, and virtually the most reliable deep cycle battery available. These batteries perform better and last longer than any other deep cycle battery.

The 100 Ah LiFePO4 12 battery is the US-made and can qualify for the best battery for a solar system in the market.

The most distinctive features of these batteries include:

• Built from non-toxic materials which are 100% safe
• Can last for 3000-500 cycles with 100% discharge depth
• Operates comfortably in extreme temperatures
• Long lifespans
• 100Amp constant output
• Full replacement warranty of 8 years and a 2-year prorated
• Fast recharge

5. Renogy Deep Cycle Pure Gel Battery 12V 200Ah

Renogy company is a renewable energy firm that produces high-quality batteries which are considered as being among the best solar batteries in the present market. Deep-cycle gel batteries are specially built to serve the off-grid solar power market. These types of batteries will provide maximum storage with any setup.

Since it’s a pure gel battery, you don’t require any maintenance checks or monitoring.

This is possible because of the gel-like substance inside these batteries, and which makes them completely sealed other significant features of these batteries include:

• Patent design construction which guarantees even distribution of the gel electrolyte
• Long lifespan of around ten years and more
• Triples sealed construction
• High-security features, including safety valves, which prevents the battery from producing redundant gas
• Low self-discharge since they use lead-calcium grids alloy, which makes them reliable.

6. Universal Power 12V 100Ah Solar Wind AGM SLA Deep Cycle VRLA, by Universal Power Group

For those looking for a reliable and durable solar battery for their system, then Universal UB121000 12v 100AH is an excellent option.

The battery is a 4.2 star rated on Amazon, and its price is very competitive. These batteries use both gel and AGM technology to make them quite durable and efficient.

However, they offer a 12-month warranty, which is significantly short for a solar battery. The warranty downside is, however, covered by the competitive prices, as well as their numerous benefits.

Its main features include:

• UB121000 12V 100Ah Deep Cycle battery
• The battery dimensions are 12.17 inches by 6.61 inches by 9.16 inches and a weight of 63.93 Lbs
• UB121000 12V 100Ah is maintenance-free and is spill-proof
• Rechargeable can be mounted at any angle, and its shocks and vibration resistant
• The battery can also operate comfortably at various temperatures

Although not as light or small in size as most batteries, this can seem like a minor drawback when you consider the benefits.

Which solar battery best suits you?

Equipped with all the above information, all you need to do now is to determine what your power needs are, along with your budget

If you have these two details, you can easily select from the above list and get tremendous solar battery storage for your solar system.

These are all great options for anyone seeking to use a battery to live off-grid.

What are Solar Batteries?

With unreliable solar battery storage, you will only be able to enjoy solar power when the solar panels are producing it.

Solar batteries are crucial to help you keep your system running.

Moreover, since the panels produce energy during the day, and you may not use all the energy at the time, a stable power bank is essential to store this energy.

With no proper type of solar batteries, you may require to contend with the lack of power, especially if there are outages in the utility grid. To get the best batteries for solar panels, here is a guide for your reference.

Solar batteries refer to devices which store the energy generated from the solar panels for later use. The solar batteries ensure that you can continue to enjoy solar power even after sundown, during a power outage or the energy demand peaks. These batteries can be used in residential properties, as well as in commercial buildings.

Solar batteries play a vital role, especially in the off-grid solar systems. They act as the heart of the off-grid solar system.

When building a solar power system, solar batteries should be a priority as they will determine how effective the system will be to you.

Using the batteries, you optimize your ability to use solar power daily. In instances where you require more energy than your panels produce, you can readily use the stored energy from the batteries.

What is a Solar Panel Battery Pack?

A solar panel battery pack is a package that makes up the solar power storage in a solar system. The first items in the pack are the solar panels that help to collect sunlight energy and change it into DC electricity.

Secondly, it we what the battery system (what you are reading about right now!) that enables the storage of the power the panels produce.

And finally, an inverter which converts the direct current (DC) to alternating current (AC) that is usable in homes.

How Does a Solar Battery Work?

The solar batteries work by storing the energy generated from the solar panels during the day. They save the energy in the form of DC energy and therefore, you will require a power inverter to convert the DC energy into AC energy.

Mostly, you will need either 120V or 230V for use in your home.

Another vital component of solar batteries is the solar charge controller. This helps to ensure that the energy produced during the day does not overcharge the batteries.

Also, it prevents the power stored in the cells from running back to the panels and draining the batteries over the night.

How to Select the Best Batteries for Solar Systems

Whereas there are numerous advantages of acquiring a battery system for your solar, there are also multiple challenges in finding the right ones. The fact that they are expensive and hard to replace after installing the solar system makes it more crucial to choose right.

There are many solar battery types in the market, that may prove challenging to differentiate, and that’s why I will show you the best way how.

The different challenges that occur during the purchase include cost, ease of installation, storage capacity, and battery lifespan, among others.

To save you the struggle, let us delve into it and see how you can choose the best batteries for solar panels.

The Different Categories of Batteries

To better understand how you can easily choose the right solar battery, you should first know the broad classes of these batteries.

There are three options of cells you can choose from which include the sealed lead-acid, flooded lead-acid, and lithium batteries. Let’s go through them one by one to help you understand.

1. Flooded Lead Acid Batteries

For the longest time, the most popular solar batteries for a home have been the flooded lead-acid batteries. This model of solar cells has been in use for over 150 years and has been a great asset, especially to the off-grid systems.

Flooded lead acid batteries, also referred to as wet cells, are very affordable and are also 99% recyclable.

With their design, they can easily handle the daily charge cycling. The significant advantages of these batteries include their low purchase cost, reliability, and safety. However, this category of cells has a good measure of drawbacks.

These batteries are known to produce a byproduct in the form of a gas, and therefore, ventilation is essential where they are located. Another major disadvantage is that they are bulky and corrosive. Also, they demand maintenance checks regularly. The batteries must also be kept in an upright manner to avoid leakage.

Flooded lead acid batteries are made of cells whose plates must be kept underwater for them to function correctly. This is the reason they are referred to as “flooded.” You need to check and add water every after 1-3 months to ensure the plates remain submerged.

For those who don’t mind the regular maintenance and monitoring, these can be the right choice. They are also the most affordable category of solar batteries.

However, due to the multiple drawbacks, many most homeowners are shifting to the use of other models which have fewer maintenance demands.

See Related: Solar Panel Lifespan Guide

2. Absorbent Glass Mat (AGM) Batteries

The second category of batteries is the AGM Batteries. From the early 1980s, this technology started gaining popularity with a sealed lead-acid battery being made for the military vehicles, aircraft, and UPS. These AGM batteries are part of a category of lead-acid batteries called the sealed lead acid.

In this form of a lead-acid battery, a fiberglass matt is used to absorb the electrolyte.

In the AGM batteries, the plates are either flat just like in the flooded lead-acid, or coiled into a spiral resembling those in Optima batteries.

One primary advantage of AGM batteries is that they possess a lower internal resistance than that in flooded cells. Therefore, these batteries can endure higher temperatures, as well as discharge slowly, more than the rest of the batteries.

Unlike the flooded lead cells, the cells in AGM batteries are leak-proof, and they also require less or no ventilation. However, just like the flooded batteries, they use the same charging voltage and tend to be more well-suited for solar electricity systems.

This compatibility means that they can be integrated with flooded cells, although we mostly don’t advocate for the setup due to the negative effect on battery life.

The other advantages of using AGM batteries include the fact that they are not hazardous, their resistant to cold temperatures, and they are relatively lightweight.

Also, they are less prone to heating up (due to the low internal resistance), and they can also preserve a static charge for long periods. AGM batteries, unlike the flooded batteries, have a longer lifespan and just slightly expensive than their counterparts.

Generally, they are an excellent choice for an off-grid solar system.

3. Gel Batteries

Another type of sealed lead-acid batteries is the GEL Battery. These batteries specialize in deep-cycle applications and use fumed silica to form the thickening agent for the electrolyte. The fumed silica helps to make the cells sturdier.

Some other advantages of Gel batteries include that they durable, requires no maintenance, and they have high resistance to vibrations and shock. The cells also work well in both hot and cold temperatures and have great life-cycles. Also, with the viscous electrolyte, the cells become less prone to leakage in case of damage.

Nonetheless, GEL batteries have more disadvantages than the other types of batteries, making them less popular. These batteries are ventless and they self-discharge a bit faster than the flooded cells.

Other common disadvantages of this category of batteries include their narrow charging profiles, and they are easily damaged if charging is not done right.

The batteries also lack ample amp-hour capacity, and their low charging voltage can make them disposed to accidental overcharge.

Especially with solar power systems, electricity generation is a bit variable and can cause this overcharging. In addition to the numerous drawbacks, Gel batteries are also more expensive than the flooded lead-acid batteries.

4. Lithium-ion Batteries

The last category in this list is lithium batteries. They consist of a newer technology that became available from the 1970s and has been in use mostly in cellphones and laptops. However, the cells have become increasingly popular in the renewable energy industry in recent times.

Although more expensive than other types of batteries, lithium batteries offer multiple benefits that compensate for the price.

These advantages include longer lifespan, higher efficient power usage, no maintenance, deeper discharges (more storage capacity), no gas emission, and more. These can typically be the best batteries for solar panels.

In the recent past, people have increasingly shifted from the traditional flooded lead-acid batteries and are more focusing on lithium-based cells.

They are also instrumental in cordless power, including cordless air compressors, and cordless impact wrenches among others. These batteries are small in size and are significantly light judging by their high capacity.

Lithium-ion batteries are easy and efficient to charge, and also, they have long lifespans. The long lifespan is the main advantage of lithium batteries as it ranges from 3000-5000 cycles.

Their high and efficient charge and discharge also is a plus as it helps to optimize the power generation from the solar panels.

The low discharge feature is ideal in solar installations as it helps retain power for more extended periods for later use. With all these benefits lithium batteries are an excellent choice for your solar panel battery bank.

Any solar system, whether small or large, grid-tied or off-grid, lithium batteries are ideal for all. One major disadvantage of lithium solar batteries is their cost.

They can cost as much as four times more than the flooded solar cells. But if price isn’t your main concern, there’s no denying Lithium-ion make for osme of the best solar batteries.

What is the best voltage for your solar battery system?

The voltage question may seem irrelevant, but it is essential. Before you buy and install that battery energy storage system, you should decide which voltage your battery system will be made of.

For example, the batteries can either be 12V, 24V, or 48V. Which fits your needs better? This is something you should be aware of before the installation.

Since it is challenging to change the voltage after installing your power storage system, it becomes critical, therefore, to make the correct choice. The 12V battery is the purest form of battery and the most commonly used one in cars, boats, RVs, and more. If you require a simple power storage system, then the 12V battery system will be enough for you.

Presently the 24V and the 48V storage systems are the most commonly used in the solar systems. The reason behind this is the technical advantages they have as compared to the 12V.

In essence, higher DC voltages translate to lower costs. It also translates to a lower current for a similar amount of power.

For example, 2,000 Watt is equal to 166 amp @ 12V, 2,000 Watt is equal to 83 amp @ 24V and 2,000 Watt is equal to 41.5 amp @ 48V

Moreover, as more and more customers seem to require more energy over the years, the 12V DC system is not ideal. If for instance, your solar panels exceed 500 watts, you should consider a 24V system. On the other hand, if you plan to live off-grid, the 48V system will be ideal.

Use an electrician to help you to determine the optimal performance.

What to Consider When Choosing a Solar Battery

Even with all that information, you may still not be ready to jump into that purchase.

There are several factors you should always research before making that final choice. These features include:

The Size of the Battery

The battery size is the first most crucial thing you ought to consider when buying a solar battery. The size in this context means the energy storage capacity of the battery. Although the physical size of the battery will also matter based on the space you have for installation, the capacity is most important.

When looking at size, you should consider both the capacity and the power rating. For instance, a battery with low power rating and high capacity will only power a few appliances in your home, but for a long time.

On the other hand, if it has a low capacity but high rating power, it will power most of your appliances but for a shorter period.

Therefore, you should look for a battery with high capacity, as well as a high power rating. With this kind of a cell, you can power multiple appliances at your home, and for more extended periods.

Ease of installation

If especially you have no much prior knowledge on the solar systems, you require a battery system that is easy to install. Essentially, it is wise to seek advice on the same from people who have prior experience or professionals.

If you want a battery system that is maintenance-free, easy to install, and that requires relatively low space, the lithium-ion batteries are your best choice.

Don’t go for a system that will consume a lot of space or that will require so much expertise to install. The easy it is to install, the less time it will absorb and most probably, the less installation cost you will incur.

If you have a larger generation need for off-grid applications, you’ll likely want to consider hiring an electrician. This will help ensure that you have the appropriate installation upfront.

Cost

When it comes to purchasing any item, the cost is a significant influencer. In selecting the best batteries for solar power storage, this is no different.

Although not always, price, in most cases, reflect the quality of an item.

Therefore, don’t rush into buying a battery just because it is cheap. You should consider all the other factors and compare them to the price.

As a general view on the solar panel battery cost, the higher the battery costs, the more benefits that come with it.

Charging Time

With charging time, some batteries charge faster than others. Different battery types will have varying charging rates with others being fast and others slow.

If you want to maximize the amount of energy generated from your solar panel system, then you need a fast charging solar battery. For those who care about the rate at which the battery charges, Gel batteries are the best choice for you.

Other categories of solar batteries such as the flooded lead-acid ones, take considerably more extended periods. They can take as long as even a whole day to get fully charged, which is long. Lithium-ion batteries, on the other hand, also have good charging speeds of around 3 hours.

If the battery charges fast, then the better for you as you can use the energy as fast as possible. A combination of an ideal battery and an excellent solar battery charger is vital to guarantee high charging speeds.

We have a full guide to solar battery charging you can check out to learn more.

Manufacturer Warranty

A manufacturer’s warranty is the next most crucial thing that you should take into consideration. Since the solar batteries are significantly expensive, you can’t afford to have a breakdown in the next few years after installation. It is wise to ensure any malfunction that may occur will be sorted.

The longer the warranty period, the best it is for you. Typically, more expensive brands offer more extended warranties than the less known and cheap ones. For solar storage batteries, a reasonable warranty period ranges somewhere from 20-30 years.

The Lifespan of the Battery

The lifespan of a battery means the period the battery will be useful before it loses its ability to hold a charge. You can measure solar batteries’ lifespan in terms of hours, days, or years, and the length depends on the type, size, or brand.

If you need a sure long-lasting and robust battery, be ready to dig a bit deeper into your wallet.

Long-lasting batteries will, in most cases, cost more than the lesser durable ones. Each brand of battery has its estimated amount of time they will remain useful. You should carefully check on this before you decide on the Solar cell to purchase.

Conclusion on Best Batteries for Solar

When it comes to solar power systems, energy storage is of paramount importance. For you to enjoy solar energy, especially if you live off-grid, reliable solar energy storage is a must-have.

In this solar battery buyer’s guide, I believe that you will get everything you need to help you choose the best batteries for solar power to suit your needs.

For most peoples needs we recommend the Vmaxtanks VMAXSLR125 AGM 12V due to their excellent performance, long life span and relative value for money.

If you’re looking for a cheaper option, the ExpertPower 12v 33Ah Rechargeable Deep Cycle Battery is also a solid choice.

We hope you’ve found this guide helpful in deciding which battery to buy.

kW vs. kWh: How to Determine the Difference (And What They Mean)

While most people would not tell the difference between kW and kWh, it is essential that we try to make them do. Kw vs. kWh is a concept that even some energy professionals don’t fully understand.

However, if you want to know the amount of electricity that you need in your home or business, it becomes critical for you to identify the difference.

If you are one of those people who regularly use the words interchangeably without knowing which one is which, then this article will be ideal for you.

Also, if you can put a distinction between kWh vs. kW will help you to understand your energy bills better. You can even understand how different appliances or machines in your home or business consume energy.

To better comprehend the two terms, we will first try to explain each word independently and then compare them. This article will offer the detailed meaning of these terms in the simplest forms to help you relate better.

Simple definitions: Kw vs. kWh

A simple definition of kilowatt (kW) would be to say; it is the measure of power. On the other hand, a simple definition of kWh (kilowatt-hour) is the measure of energy.

The initials stand for;
K – kilo (1000)
W – Watts
H – hours

Although it may seem simple, many people even after seeing these terms for the longest time, still can’t figure out the difference. Also, the terms energy and power may tend to complicate things even further.

Just like kW vs. kWh, energy and power are words that people always use when they meant to mean the other.

For this reason, it is crucial that we understand the difference between the two so that we can easily understand kW and kWh.

What is Power?

Power can be defined as the rate at which energy is used or generated at any given time. When we talk of how much power an appliance or an electronic need to operate at any given time, we speak of kilowatts (kW). It is the electricity load.

Just like a moving car where speed can be defined as the rate at which distance is covered, the same way power is the rate at which energy is consumed or generated.

As kW is the measure of power, the higher the kW a building needs to operate, the higher the rate at which it is consuming energy. There are 1000 watts per kW and therefore, to determine the kW of an item that is rated in watts, you divide by 1000.

When it comes to solar panels, the size of the panel will be defined using its peak power. The peak power is the amount of power the solar panel produces at maximum sunlight.

For example, a 2-kW solar panel will produce 2 kW of power on a hot day.

See Related: Best Solar Panels to Buy For Home

What is Energy?

Energy refers to a measure of how much fuel something contains, or uses over a definite period. Therefore, when we say that kWh is a measure of energy, we mean that it is the total amount of energy that you can use over a stated period, let’s say an hour.

For example, if you have a machine that requires 1000 watts to operate, and you run it continuously for one whole hour, it means that you spend 1000 watts or 1kWh of energy. It is merely the number of kW that an item will require to function for a given period.

The total measure of electricity you can use (or generate) is what we define as kWh. Some, for example, can say, “My solar system generated 3 kWh of energy today!”

In other words, if you have a light bulb rated at 100 watts, it will take the bulb 10 hours to exhaust 1kWh of energy. A 50-watt light bulb will stay on for 20 hours for it to consume 1 kWh, while a 2 kW item will take half an hour to exhaust the 1 kWh of energy. Like these stats? Consider reading about these facts about electricity.

You can use our potential energy calculator to determine the energy of an object.

See Related: What is Net Metering and How Does It Work

How to Determine the Difference between kW and kWh

Using the above definitions, we can now look at a comprehensive example to help us get the concept even better. For our case, we will take two models of cars, traveling at different speeds, but for the same period.

Since kW is the measure of the energy that something needs to operate, it is sometimes referred to as the “demand” while kWh as the “consumption” or “usage” as it’s the energy spent over a while.

Back to our example:

While the two cars travel for the same period, we can see a big difference in terms of the distance covered by each vehicle. The Ford Escape covers a range of 500 miles after five hours since it was traveling at a speed of 100 mph. In other words, it required or demanded speed of 100 mph to be able to cover the 500 miles.

If we compare this to the demand of energy in a home or a building, we can equate speed (mph) to the kilowatt (kW), as both stands for the demand at any given time. Therefore, just as we require a rate of 100mph at any given time for the Ford, we would need 100 kW to operate the building at any given time.

On the other hand, if we equate the total distance covered to the overall “consumption” of energy at a building, then the equation will be; Distance Travelled (mi) = The Kilowatt-hour (kWh).

If we take the Ferrari for instance, it covered a distance of 850 miles in 5 hours. This means that for the specified, which is 5 hours, the car covered 500 miles.

Equating this to the consumption of a building, we would say that our energy consumption is 500 kWh for the 5hrs. So, kWh does not mean the amount of kW consumed per hour, but rather the amount of energy something consumes over a determined period.

Since we can see that the two cars cover two different distances while operating at the same number of hours, it is also possible for two buildings to run for the same amount of time but consume different kWh.

Relationship Between energy (kWh) and power (kW)

Using the explanations above, we can see that kWh is kW multiply by time. Therefore, the equation becomes; kWh = kW * h,or energy = power * time. This shows that the two are interrelated and in the world of electricity, both are important.

For instance, 1 kWh is equal to one-hour usage of electricity at a rate of 1 kW.

It is also okay to say that 2-kW appliance will use 2 kWh in one hour.

Capacity Ratio

Another essential term we need to understand, especially for those using renewable energy as a source of electricity is the capacity ratio. Many people have installed solar systems or wind turbines but still can’t tell the difference between the actual power generated, and the installed capacity.

While determining the installed capacity is easy, calculating the actual output is the challenge.

In simple terms, the capacity ratio of a system is the actual power produced over a certain period, divided by the total installed capacity (max possible power output).

To calculate the installed capacity, you add up the rated capacity of all your solar panels.

See Related: A Complete Guide to Prepaid Electricity

Here is an example

Let’s say, if you have four solar panels rated at 2Kw each, then the installed capacity will be 2 kW multiply by four, which equals to 8 kW. Just as the actual power output varies in various locations, the capacity factor for a solar system will also vary based on site.

The difference is caused by the different solar scores found in different places.

To illustrate this scenario, we can take two different cities like Phoenix, which has a solar score of 84 and Seattle, whose solar score is 43.

If for example, we consider a solar system with a 10 kW peak capacity and install it in both cities, their capacity factor will be as follows.

If the average solar power produced in a year is 20,500 kWh, and the installed capacity at that peak capacity is 87,600 (24 x 365 x 10), then the capacity ratio is 20,500/ 87,600 *100 = 23%.

In Seattle, whose Solar Score is 43, the same 10kW system will produce 14,000 kW. Dividing this by 87,600 you get 16%.

Generally, the ratio ranges between 10-25% depending on the availability of the sun or wind in the case of the wind system.

See Related: How to Calculate Electricity Usage Charges

How Much is 100 kW

Being able to differentiate between kW and kWh is a big step in managing your power bills. Also, it is beneficial to know how these units of measures can be converted. Most manufacturers rate various appliances in either kW or watts, it is crucial to understand how to convert one to the other.

For example, if you are asked how much is 100 kW, I think the right question should be, how many kWh does a 100-kW system produce?

To clarify, the reason the question changes is because as we know, kW is the measure of power while kWh is the measure of total energy generated over a specific time.

Therefore, to answer the question, a 100-kW solar system means that the system can produce 100 kW of power at any given time with the maximum sunlight.

If for instance, the system receives maximum sunlight for a period of let’s say 4 hours, it means the panels can produce a total of 400 kWh of energy. i.e. 100 kW * 4 hours = 400 kWh.

Based on that example, we can, therefore, conclude that the amount of energy produced by a solar system, will depend on the total peak hour (kW) multiplied by the hours of sunlight.

Importance of kW vs. kWh

Although many people may assume it and view it as just scientific differences, it can significantly help you understand your power bills more. It will enable you to know how much energy you consume, what appliance consumes what power, and at what rate.

When shopping for a solar system to install, this knowledge will help you choose the right size for your needs.

For example, the average Connecticut power rate for a commercial customer is 12.22 cents/kWh or $15.45/Kw at peak hours.

Therefore, a 2-kW item that consumes 100 hours per month will incur $24.44 in consumption charges.

See Related: Fronius Smart Meter Review

Conclusion on kW vs. kWh

Having a clear distinction on Kw vs. kWh is essential to help realize the amount and rate at which they consume energy. I hope this article provides you with everything you need to know about the differences between kW and kWh.

Is this article on the difference between kW vs. kWh helpful to you? Please let us know in the comments below.