How does solar battery storage work?

How Does Solar Battery Storage Work? That question has never been more important than it is today.

Solar energy is all the rage today because it is environmentally friendly and cost effective. 

If your utility bills are burning holes through your wallet, then it might be time for you to invest in some solar battery storage options.

What is a Solar Plus Storage System?

Their purpose was to harness the power of the sun and then funnel it into the average household, and nothing else.

Over time, it was determined that the convenience and efficacy of solar systems could be augmented if they were combined with battery storage.

And so, solar plus battery storage systems were created.

What is a Solar PV System?

Solar energy technologies are primarily available in two forms, namely: Solar PV and Solar Thermal systems.

Solar thermal systems are not as common. They involve generating heat using the sun’s energy and then making electricity from that heat.

If you are shopping for solar power, though, most professionals will direct you towards solar PV systems.

These are what you will find in most households and their operations are pretty straight forward.

Solar PV systems have solar cells. Solar cells are the building blocks of solar photovoltaic technology.

Each cell consists of two layers of silicon (though manufacturers have also been known to use other semiconducting materials).

When the solar panel is deployed outside and the solar cell touches the sun’s rays, an electric field manifests across the layers of silicon.

This causes electricity to flow. The amount of power generated is determined by the intensity of the sun’s light which, in turn, determines the flow of electricity.

The amount of electricity a solar cell can produce is referred to as kWp (Kilowatt peak).

Solar PV systems have modules which take the energy gathered by the PV cells and convert it into Direct Current.

An inverter then turns that Direct Current into Alternating Current. Most homes use AC.

Battery VS Non-Battery PV systems

You can use a solar PV system with a battery and without one.

The battery option is what most professionals encourage homeowners to get.

When the sun is at its strongest, a battery-powered PV system will generate and then store excess electricity.

You can then use that additional electricity later on when the power generation capabilities of your PV system deteriorate (primarily when the sun sets).

A Non-battery powered PV system is just as effective. The battery option is supposed to avail you extra power when the sun goes away.

However, most solar-powered homes are still connected to a local Power grid.

So even if you have a non-battery powered Solar PV system, if your solar panels fail to generate the power you need, you can always cover that deficit by drawing power from the grid itself.

Either the way, you are sorted. The battery option is only attractive because it gives you the option of going off the grid completely.

Batteries are especially useful for homes that are so remote that they cannot connect to the central utility grid.

How is Solar Energy Stored in Batteries?

If you contract an energy company to furnish your home with a solar system, they will install solar panels, an inverter, and a monitoring mechanism.

This system will harness the power of the sun during the day and turn it into electricity that you can use.

If your home is connected to an electricity grid, which is often the case, any solar-generated electricity you don’t use will be sent to the grid.

The homeowner gets credit for the extra electricity their system generates and then sends to the grid.

This is on top of being able to draw extra power from the grid on those occasions when the solar panels are incapable of generating the electricity you need to run your home.

A lot of homeowners use this approach to manage their bills. They generate power from the sun, sell the excess to the electricity grid and take advantage of the savings.

But you also have those who install batteries that take that extra solar power and store it for later use.

Such solar batteries act as a reserve.

Solar Battery Storage systems come in many types but the AC Coupled, DC Coupled and Hybrid inverter versions tend to stand out.

01. DC Coupled Storage

This approach isn’t as common as the AC Coupled type.

The Solar battery storage technique involves inserting a system between the inverter and the solar panel.

When your solar panels generate excess power, this system will sense it and automatically send it to the batteries.

That power is only converted into AC after it is stored in your batteries.

This system comes into play when you begin using more power than your solar panels can generate.

The system steps in by releasing power into the inverter to make up for the deficit.

Some people like this method because it is not only cost effective but easy to install into existing systems.

Others hate it because it cannot draw and store power from the grid. Neither can it step into power your home in case of a grid outage.

02. AC Coupled Storage

AC storage systems are also designed to store excess energy in batteries.

However, they are more popular than DC coupled systems because they can store excess solar energy, draw power from the grid, and operate independently of solar power systems.

They are not as cost-effective when it comes to storing solar power but they allow individuals to buy power at cheaper rates.

The fact that they are more expensive hasn’t stopped people from buying them.

03. Hybrid Inverters

Hybrid inverters combined AC and DC coupled systems.

Like DC coupled systems, hybrid inverters will store power before converting it to AC, making future conversions unnecessary.

But like AC Coupled systems, you can buy and store power at cheap rates.

You won’t find many of these in the US but they are starting to gain traction.

People like them because they have one unit from where all the monitoring is done.

How a Home Solar Battery Storage System Connected to the Grid Works?

On Grid Solar diagram

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Off Grid Solar diagram

The average Solar PV system that is connected to the grid requires the following components to operate:

01. Solar Panels

This goes without saying. Every solar system requires solar panels to harness the power of the sun.

These panels are installed on surfaces and at angles that expose them to the greatest amount of sun for the longest period of time.

And they can actually generate energy on cloudy days. These devices are categorized according to the amount of power in Watts that they can produce in one peak hour.

Solar panels are marketed and priced according to this classification.

02. Inverter

When the solar panels generate power, the inverter is the device responsible for converting it into AC electricity that most homes use.

You can either configure a micro inverter system in which each solar panel has an inverter attached to it.

Or you can prioritize the string inverter approach which connects multiple solar panels together and transmits all the power they generate into a single inverter.

You can also buy string inverters that use power optimizers to manage (Monitoring and control) the individual panels to maximize their efficiency.

 03. Switchboard

When your inverter finishes turning the Direct Current from the Solar Panels into Alternating Current, a switchboard takes that power and directs it to the items and appliances in your home that need it.

The switchboard is also responsible for detecting any excess electricity and either storing it in a battery or sending it to the central grid.

04. The Meter 

Switchboards work with meters to determine how much power you are sending to and from the electricity grid.

Depending on your location, your metering system might receive your power before it reaches the switchboard, thus allowing it to measure all the solar energy you are generating.

In other words, the meter isn’t just measuring the power going to and from the grid.

It is through the work of the meter that a household is charged and credited for the power it sends to and from the grid.

05. Regulators/Controllers

These devices manage the amount of power being transmitted from the solar panels.

Their purpose is to prevent your solar system from overcharging its batteries.

They are what you rely on to sense when your battery is full and to stop the flow of current.

This same device will prevent the battery from feeding power back into the solar panels at night.

06. Solar Batteries

Solar systems use deep cycle solar batteries. These are devices that can withstand and survive a multitude of charge and recharge cycles.

Unlike normal batteries, you won’t cause damage by fully discharging and then charging them over and over again.

Solar batteries are rated in Ampere Hours.

The larger a battery, the more power it can hold.

What Size of Solar Battery is needed?

Your choice of battery should take your power needs into account.

You generally measure energy usage in kilowatt hours. So if you have a thousand watts, ten daily hours of usage will equal to ten-kilowatt hours per day.

If you can figure out your daily energy usage, determining the size of the battery you require isn’t that hard.

After that, you can proceed to select the type of battery that works for you.

The most common types Solar Battery include

 Flooded Lead Acid Battery –

 This one can last up to seven years. It requires a lot of maintenance but the low upfront costs make up for it.

Sealed Lead Acid – 

These batteries are quite expensive. They have a lifespan of three to five years.

Lithium – 

These are the most expensive batteries on the market. They are also the most popular, probably because they last more than ten years and they do not require maintenance.

You need to take the pros and cons of each battery type into account before making a choice.

Solar Battery Savings with Time-Of-Use Rates

When people talk of Time-Of-Use Rates’, they are referring to the electricity rates that your local utility company sets.

TOU rates vary with time. In other words, you have peak hours when electricity is most expensive because demand is high.

You also have off-peak hours when the demand is so low that electricity becomes really cheap.

TOU rates are designed to encourage homeowners to reduce their energy consumption during peak hours.

Solar storage systems will help you reduce your utility bills by only utilizing electricity from the grid during off-peak hours when the power is really cheap.

And then once peak hours roll around and the demand grows, the solar system will dip into your battery to power your home, thus preventing you from using the grid at a time when TOU rates are so exorbitant.

Some studies have suggested that households which use solar batteries can save nearly $500 during peak hours over the course of two weeks, which is impressive.

Should You Install a Solar Battery At Your Home?

When you tell people about solar storage batteries and you explain how they work, they are quick to make the jump to the solar storage battery system.

However, just because you have solar power doesn’t mean you have to install a solar battery.

A solar battery will help you store additional power for later use.

Your dependence on the local grid will also reduce. However, if you have a battery, then you can’t take advantage of the savings provided by net metering.

If you can produce excess power via your solar system, sending that extra electricity to the grid will earn you credit.

But if you have a battery and all your excess power goes into that battery, you won’t enjoy the financial compensation acquired from net metering.

On the other hand, if you prefer to send your excess power to the local grid, then you have no use for a solar battery.

Ultimately, you need to determine which situation works best for your household.

Benefits of Solar Battery Storage

Optimization  

solar batteries allow you to make the most of your set up.

With a normal solar system, once your solar panels fail to generate sufficient power, you are forced to rely on the electricity grid to cover the deficit.

Solar batteries allow you to depend solely on the sun by saving any excess energy you generate for later use.

Security  

If you live in places where the grid is unstable, solar batteries will give you peace of mind.

You can know for certain that your energy needs will be met regardless of whether or not the central grid is online.

The Environment 

 Solar Battery storage systems are environmentally friendly.

Using a solar battery will reduce your carbon footprint whilst also making you self-sufficient.

Noise 

People that are looking to attain self-sufficiency in the area of energy production often tout generators because they are typically cheaper than solar systems.

However, unlike generators, you do not have to worry about noise pollution with solar systems.

Money 

Solar batteries will significantly reduce your utility bills by allowing you to save and utilize the excess power you generate during off-peak hours.

How Much Do Solar Battery Storage Systems Cost?

Even though talk of solar energy is so rife today, people are still hesitant to give the technology a shot because of the costs involved.

One of the more popular solar battery systems available is the Tesla Powerwall and it can cost you as much as $6000.

That includes a battery inverter. The system boasts a 7kW, 5kW peak constant draw, and it is definitely one of the more appealing options.

But you also have systems like the Sonnen EcoLinx on which you must spend a minimum of $16,000.

Solar systems are very expensive. However, you can pay for them in installments over the course of several years.

Also, the technology gets better and cheaper with each passing day.

Conclusion

Ultimately, everyone should consider investing in solar battery storage systems.

Even if your local grid is stable, the benefits of solar battery storage systems are too significant to ignore.

In the long run, the money you save on utility bills will more than make up for the upfront cost of acquiring a solar battery storage unit.