Battery Basics Guide to Energy Storage Systems - c3controls

Introduction

In 2021, the entire world consumed around 604 quadrillion British Thermal Units (Btu). Americans consumed about 16% of the world’s total primary energy consumption, which was around 98 quadrillion Btu.

As we begin seeing the results of our dependence on fossil fuels affecting our environment, there is a growing demand for greener energy options.

Renewable energy technologies like solar and wind, however, have variable outputs. Which is why experts and consumers are looking into home energy storage systems. There are several types of batteries that can help us rely less on fossil fuels while receiving a steady flow of energy.

Since home energy storage is growing in popularity, we’ve created a guide to help you out. Keep reading to learn about the process of residential energy storage systems and battery basics.

Battery Basics: Why Residential Energy Storage is Important

While renewable energy technologies are available, there are some geographical locations that don’t receive a lot of wind or sunlight.

Residential homes, especially those further away from the energy grid, are often more vulnerable to disruptions than homes located in metropolitan areas.

Stored Energy Equals Steadier Supplies

Being able to store energy helps ensure every home receives a steady supply of energy no matter where they’re located. Also, while fossil fuels take a longer time to ramp up, energy storage is known for its rapid response. This ensures greater stability of the grid during times of increased demand.

Types of Batteries

Besides having steady supplies of energy, creating stored energy supplies also helps reduce costs. Storage owners and operators stand to receive additional revenue.

There is currently a wide array of technological approaches to help manage our supplies and create a resilient energy infrastructure. To help explain these varied approaches, they’re divided into these main categories:

Compressed Air Energy Storage

This type of storage is accomplished by creating energy reserves by using compressed air. It uses the elastic potential energy of compressed air which improves the efficiencies of conventional gas turbines.

By compressing air using electricity during off -peak hours, the air can then be stored in underground caverns. When demand peaks, the air is drawn from storage, fired with natural gas in a combustion turbine and generates electricity.

Uses Less Natural Gas but Limited by Geography

Only a third of natural gas is used through compressed air energy storage than other conventional methods. However, due to its need to use underground reservoirs, its use is limited by its locations.

Flow and Solid-State Batteries

Solid state batteries offer a wider array of electrochemical storage solutions. This includes capacitors and advanced chemistry batteries. With both types of batteries, the energy is stored directly in the electrolyte solution. This is done to increase its cycle life and provide users with quick response times.

Excellent Storage for Distribution and End-Use

Batteries can be located anywhere. As a result, they make excellent storage for distribution. A battery facility located near consumers provides power stability. For end-use, they’re used in electric vehicles.

Variety of Batteries Available to Store Energy

Many types of batteries offer large-scale energy storage potential such as:

• Metal-air
• Lithium
• Ion
• Sodium-sulfur
• Lead-acid

Some wind farms also have battery installations. They help provide stability in power supplies when the wind isn’t blowing.

New battery technology advancements are helping battery costs decline.

Flywheels

Flywheels are mechanical devices. These devices deliver instantaneous electricity by harnessing rotational energy.

Flywheels store electricity in the form of a spinning mass. This method can provide a variety of benefits to the grid at either the transmission or distribution level such as:

• Long lifetimes
• Require little maintenance
• Highly efficient
• Rapid respond times

Shaped like a cylinder and containing a large rotor inside a vacuum, flywheels draw their power from the grid when the rotor accelerates to extremely high speeds. Electricity is then stored as rotational energy.

Stored energy is discharged when the rotor switches to generation mode, slows down and then runs on inertial energy. Electricity is then returned to the grid.

Flywheels can also be placed almost anywhere, even close to consumers. Flywheel farms can produce megawatts worth of energy while a single flywheel can produce kilowatts worth.

Pumped Hydro-Power

Hydro-power occurs when water is used to create large-scale reservoirs of energy. It’s a way to store energy at the grid’s transmission stage. Its excess generation is then stored for later use.

Many hydroelectric power plants keep two reservoirs located at different elevations. When supply exceeds demand, water is pumped into the upper reservoir to store energy.

An Expensive Way to Generate Electricity

Water is released into the lower reservoir when demand exceeds supply. The water runs downhill through turbines which generates electricity.

Today, pumped-hydro storage is the largest storage system in operation. However, it’s a long permit process and pumped storage is expensive.

Hydrogen

For generation purposes, hydrogen can be used as a zero-carbon fuel.

It’s possible to create hydrogen by using excess electricity. It can then be stored and used later in engines, gas turbines, or fuel cells to generate electricity without harmful emissions being produced.

Hydrogen Fuel Cell

Research Continues on Harnessing Energy When Wind Isn’t Blowing

Research is still being conducted on how to create hydrogen from wind power and storing it within wind turbine towers to use as electricity generation when the wind isn’t blowing.

Thermal

Thermal captures cold and heat to create on-demand energy. It uses power from the sun, even when the sun isn’t shining.

Heat is captured from the sun. Its energy is then stored in molten salts, water, and other fluids. That stored energy can later be used to generate electricity, even after sunset.

Thermal Energy and End-Use Storage

You can also use thermal storage technologies for end-use energy storage. By freezing water at night utilizing off -peak electricity, when the stored cold energy is released from the ice, it can help with air conditioning during the day.

Various Types of Batteries for Home Energy Storage

As mentioned, there are several different types of batteries that can be used in home energy storage.

Flow Batteries

There are many types of flow batteries such as:

• Vanadium redox
• Zinc bromine
• Iron-chromium

Flow batteries offer low energy density. Their requirement to pump liquid electrolyte also complicates the operation. Round trip efficiencies are low, between 60%-70%. They come with exceptional life cycles and are a good cost for high energy low power configurations. Technology is improving which should lower costs.

Lead Acid

Here’s where lead-acid batteries fail:

• Poor cycle life
• Poor power
• Poor energy diversity

Poor deep discharge capabilities also limit its versatility. However, lead-acid does provide an excellent cost per kWh.

Lithium Ion

There are several types of lithium-ion batteries such as:

• Nickel manganese cobalt (NMC)
• Nickelate (LNO)
• Nickel cobalt aluminum (NCA)
• Iron phosphate (LFP)
• Manganese spinel (LMO)
• Titanate (anode) (LTO)

Manganese spinel and nickel manganese cobalt are the most common. However, iron phosphate and titanate are becoming more commonly used in grid applications as well.

Benefits of Lithium Ion

Lithium-ion batteries offer the following benefits:

• High power
• Efficiency up to 90%
• Versatility anywhere from 15 minutes to four+ hours
• Maturity

Lithium-ion batteries can be used in a variety of applications outside the grid. Its cycle life is considered good to excellent.

Cons of Lithium Ion

However, the costs can be high as the power to energy ratio decreases. Lithium ion batteries also require cell balancing electronics. The environmental costs of lithium batteries are starting to be recognized as well.

Sodium Beta Alumina

Sodium beta-alumina batteries offer a good to excellent cycle life. The two types are:

• Sodium sulfur
• Sodium nickel chloride

Sodium Beta Alumina Batteries Pros and Cons

All sodium beta alumina batteries operate at high temperatures of around 300°C. They also require between four and six hours of energy storage per unit power. Depending on their operational profile, they offer good round trip efficiencies of up to 85%. However, if the batteries sit idly, that profile drops. Sodium beta alumina batteries also require heaters in order to prevent freezing. And those heaters consume power constantly.

How Batteries Work for Home Energy Storage

Batteries are often preferred because of their myriad commercial and residential use applications. That’s because battery energy storage systems are rechargeable.

Rechargeable battery systems store energy from either the electric grid or solar arrays. It then can be used to provide energy to homes and/or businesses.

Battery energy storage systems contain advanced technologies regular batteries do not. This enables them to perform tasks such as load shifting and peak shaving.

Three Steps to Battery Energy Storage Systems

There are three basic steps to battery energy storage systems:

1. Charge:
   During daylight, battery storage systems are charged by clean electricity. All of which is generated using solar.
2. Optimize:
   Battery software uses algorithms. These algorithms coordinate the following and helps the batteries optimized when their stored energy is used.
   a. Solar production
   b. Usage history
   c. Utility rate structures
   d. Weather patterns
3. Discharge:
   During times of high usage, energy is discharged from the battery storage system. This reduces and/or eliminates expensive demand charges.

Benefits of Modern Batteries for Home Energy Storage

Batteries for home energy storage offer consumers cost savings. They also offer energy suppliers with new ways to earn more money. But they also usually include a built-in inverter as well as computerized control systems. These all-in-one turnkey systems are efficient due to the following reasons:

• Easy to install
• Mostly maintenance-free
• Require no expertise or effort from the owner
• Weatherproof

Modern batteries for residential energy storage are also safe for pets and people to be around. However, there is a growing trend for do-it-yourselfers to build their own Battery Storage Systems.

A residential grid-tied Battery Storage system, either off the shelf or DIY, needs to meet NEC requirements. These are the same types of electrical components used in industrial electrical and control systems.

• A junction box
• DC Disconnect
• Overcurrent Protection
• Ground Fault Protection
• Net meter socket (if tying back to the grid)
• AC Disconnect
• DP Circuit Breaker (for the wiring from the PV system to the grid)

Energy Storage Applications for Residential Use

There are several beneficial applications for home energy storage systems.

Emergency Backup

With the number of storms increasing, it’s important to have a residential energy storage system that keeps the power working, even when an outage occurs. Battery energy storage works efficiently whether it has access to solar power or not.

It’s also a safer and more seamless alternative to small generators. Especially since generators are one of the main contributors to carbon monoxide poisoning in the US.

Off-Grid

Some people have chosen to go off-grid and generate their power using solar energy. Thanks to modern technology, those DIY’ers now have a battery energy storage system that far exceeds the capabilities of marine lead-acid batteries used in the past.

Also, newer and more modern battery energy systems are easier to configure, install, and are more scalable. They’re also far safer and when comparing them per kWh of storage, are much cheaper.

Home "of the future" with energy storage system

Solar Self-Consumption

Most homeowners are concerned with the application of solar self-consumption in residential energy storage systems. This system allows homeowners to store any surplus energy produced by their solar panels during the day.

Homeowners can then use that stored solar energy at night. For those customers on utilities without net metering, solar self-consumption is a great option.

Conclusion

While many emerging home energy storage technologies remain to be proven, it is clear that battery energy storage systems do and will help radically transform how consumers interact with energy.

Batteries will help make solar a must-have for homes and businesses. Batteries should also bring greater independence from the traditional utilities we all currently depend on. New doors should open offering a greater diversity of energy options.

Understanding battery basics is part of the key toward finding the best products and services for your home and business. It’s important to demand quality and excellence from those supplying you with products and services…

and c3controls is ready and able to assist! Let us know how we can help.

For an electricity system to work, the electricity being generated by power stations must be closely matched to the electricity being consumed by users. Energy storage offers numerous benefits for maintaining this delicate balance of electricity supply and demand .

1.

     

Savings

Power stations must be sized to match the maximum expected electricity demand (usually occurring on the days with the highest heating or cooling requirements), even if the average demand is much lower. With energy storage however, energy can be stored overnight (when demand is low) and then used during the high demand period of the following day. This use of energy storage is called peak shaving, which reduces the need to build and operate expensive power stations and transmission lines. The result is less waste and lower electricity prices.

2.

     

Decarbonization

Since wind and sunshine depend on daily and seasonal weather, an electricity grid cannot rely solely on these renewable energy sources if the supply-demand balance is to be maintained. To avoid reliance on fossil-fuel power stations, energy storage technologies can be charged when there is excess wind or sunshine, and later discharged when there is insufficient wind or sunshine. This use of energy storage is called renewable energy integration, which will be critical for the clean energy transition.

3.

     

Independence

Where we have previously seen a small number of large fossil-fuel power stations in a given region, we are now starting to see larger numbers of smaller renewable energy farms backed by energy storage. This is called distributed energy resources, which will allow for increased energy independence at the community level. Remote communities relying on diesel generator microgrids are also starting to reduce or eliminate their dependence on expensive, air-polluting fuels in favor of emission-free renewables and energy storage.

4.

     

Reliability

There are also a number of additional functions that energy storage technologies can perform to increase electricity grid reliability. These functions are called ancillary services, which will become increasingly important as more wind and solar energy farms are connected to the grid.

Case Study

The state of South Australia has been a global leader in adopting renewable energy, but large amounts of wind and solar power without energy storage made the electricity grid more vulnerable to an extreme wind event in 2016, which led to a state-wide blackout . The state government responded by building the world’s largest lithium-ion battery in 2017, called the Hornsdale Power Reserve. This giant battery is charged from a nearby wind farm and maintains grid reliability with greater performance and lower cost than fossil-fuel power stations. In its first four months of operation, the 90 million AUD battery saved Australians 35 million AUD in electricity costs and successfully protected the grid when a coal power station unexpectedly went offline . Due to its initial success, plans were released in 2019 to increase the size of this battery by 50% .

Get Involved!

As countries around the world take steps to develop more renewable energy and improve electricity reliability, energy storage is increasingly necessary and valuable. The main drawbacks of today’s energy storage technologies are high economic cost and reliance on mining operations that are not geared towards the clean energy transition. are not always environmentally or socially acceptable . The world needs skilled engineers and scientists to “lead the charge” in developing energy storage solutions that are both affordable and sustainable. We also need policy-makers and community members to pay attention to how new technologies are manufactured, and advocate for responsible and ethical sourcing of the required raw materials.

Dive Deeper: Types of Energy Storage :

Elevation (gravitational potential energy):

• Electricity can be used to pump water from a low elevation to a high elevation. Electricity can then be generated later by allowing the water to flow back down through a turbine. This is called

  pumped hydro energy storage

  , which is the oldest and most-used form of large-scale energy storage.

• Electricity can also be used to temporarily force massive objects uphill or straight into the air, which is generally called

  gravity energy storage

  . Several new start-up companies are trying to make these ideas commercially viable for large-scale energy storage.

  Advanced Rail Energy Storage

  uses heavy train cars on a slope, while

  Energy Vault

  uses a reversible crane-lift system with large concrete blocks.

Compression (elastic potential energy)

• Electricity can be used to compress air into a container at high pressure. Electricity can then be generated later by allowing the air to flow back out through a turbine. This is called

  compressed air energy storage

  , which has only a handful of existing large-scale projects but is now seeing increasing research and development. Some projects store the air in tanks, while others store the air in underground caverns. There is even a demonstration project where air is stored in

  giant balloons

  at the bottom of Lake Ontario.

• Springs are another form of energy storage through compression, but this technology has not been used for storing electricity at a large scale.

Rotation (kinetic energy)

• Electricity can be used to spin a massive wheel. Electricity can then be generated later by allowing the spinning wheel to slow down as it drives a generator. This is called

  flywheel energy storage

  , which is becoming popular for electricity grid applications with short storage periods (seconds to minutes).

Chemistry (chemical energy)

• Electricity can be used to change the chemical bonds in a material. Electricity can then be generated later if this chemical process can be reversed. This is called

  battery energy storage

  , which is the most popular technology for new large-scale energy storage projects today due to the wide range of suitable applications. There are many different types of batteries within this category. Lithium-ion batteries and lead-acid batteries are the most common, but other types such as sodium-based batteries and vanadium-redox flow batteries are being increasingly used as well.

• Electricity can also be used to manufacture gases such as hydrogen. Electricity can then be generated later by burning the gas or running it through a special engine called a

  fuel cell

  . This is called

  power-to-gas (P2G)

  , which has potential for long-term storage of excess renewable energy.

Capacitors (electrostatic energy)

• Capacitors are electrical devices that store electricity in an electric field rather than converting it into another form of energy. Advanced capacitor technology (called

  supercapacitor

  or

  ultracapacitors

  ) combines the designs of capacitors and batteries to allow for much more energy storage than a regular capacitor. This technology can be used for electricity grid applications with short storage periods (seconds to minutes).

Magnetism (electromagnetic energy)

• When electricity flows through a coil it generates a magnetic field. Almost all the energy stored in this magnetic field can be retrieved as electricity when the coil is cooled to very low temperatures. This is called

  superconducting magnetic energy storage

  , which can be used for electricity grid applications with short storage periods (seconds to minutes).

Heat (thermal energy)

• Electricity can be used to raise the temperature of water or other specialized materials. Electricity can then be generated later by using the high temperature to produce steam and drive a turbine. The stored heat can also be used directly for heating purposes instead of converting it back into electricity. This is called

  thermal energy storage

  , which is one of the more common energy storage types in use today.

Electricity can also be used to lower the temperature of a gas until it can be stored as a liquid. Electricity can then be generated later by allowing the cold liquid to expand into a gas and drive a turbine. The stored cold liquid can also be used directly for cooling purposes instead of converting it back into electricity. This is called liquified air energy storage or cryogenic energy storage, which is a new technology still under development.