Solar + Batteries Provide Affordable Electricity

A solar + battery system allows your home to generate, store, and intelligently use its own electricity, reducing the amount of power you need to purchase from PG&E. Solar panels produce electricity during the day when the sun is shining. That energy is used to power your home first. If your solar system produces more electricity than your home is using, the excess energy can charge your battery. Once the battery is full, any remaining energy can be exported to the grid.

The real financial advantage of combining solar with battery storage comes from how the system works under California’s NEM 3.0 (Net Billing Tariff). Under this program, the value of electricity exported to the grid during the middle of the day is relatively low. However, electricity from the utility becomes much more expensive in the evening when demand is highest. A battery allows you to store excess solar energy produced during the day and use it later, instead of purchasing high-priced electricity from PG&E during peak hours.

In a properly designed solar + battery system, the battery is typically charged during the daytime when solar production is strong. In the evening — when PG&E electricity prices are highest — the battery discharges that stored energy back into your home. This helps homeowners avoid buying expensive electricity during peak rate periods, which is where a large portion of the financial savings comes from.

Your solar and battery system also works together with the PG&E grid. The system automatically manages energy flow throughout the day, prioritizing solar production, battery storage, and grid interaction in the most efficient way possible. The system can:

• Power your home with solar energy during the day

• Store excess solar energy in the battery

• Use stored battery power during expensive evening hours

• Draw electricity from the grid only when needed

• Export excess energy to the grid when it provides the most value

Because every home uses electricity differently, the design of the solar and battery system is extremely important. Factors such as your annual energy usage, roof orientation, PG&E rate plan, and battery capacity all affect how much money you can save. A properly designed system focuses on maximizing the use of your own solar energy while minimizing the amount of electricity you purchase from the utility.

The best way to understand how a solar + battery system would work for your home is with a personalized energy evaluation. This allows us to analyze your energy usage, design the right system for your home, and show you how the system would perform under PG&E’s current NEM 3.0 rate structure.

Request your Free Solar & Battery Energy Evaluation to see how much you could save.

Most homeowners are surprised to learn that solar installation companies typically offer a small selection of high-quality solar panel brands, rather than just one option. This allows homeowners to choose equipment that best fits their energy goals, roof layout, and budget.

At our company, we offer several of the most trusted solar panel manufacturers in the industry, including REC, Q-Cells, and Hyundai. These brands are known for their reliability, strong performance warranties, and long-term energy production.

Many solar companies across the United States install Q-Cells solar panels, which are proudly manufactured in the USA and make up more than 30% of the solar panels installed nationwide. They are widely considered one of the most dependable and cost-effective solar panels available today.

Homeowners are also often given the option of a premium solar panel, such as the REC Alpha Black Series, which offers very high efficiency and strong long-term performance. In addition to premium panels, many companies offer a value line of panels, allowing homeowners to choose a solution that fits their specific budget and performance goals.

Having multiple panel options allows your solar system to be designed around what matters most to you — whether that is maximum efficiency, long-term performance, or overall value.

Equally important as the solar panels themselves is the inverter system. Solar panels generate electricity in DC (direct current) form, but homes operate on AC (alternating current) power. The inverter is responsible for converting the electricity your panels produce into usable power for your home.

Most high-quality solar systems are paired with trusted inverter manufacturers such as:

• Enphase microinverters
• SolarEdge inverter systems
• Tesla Inverter (built into Powerwall 3)

These  technologies are widely used in the industry and are known for their performance, monitoring capabilities, and reliability.

When evaluating solar equipment, homeowners should focus on several key factors:

• High panel efficiency ratings (over 22% efficiency would be considered premium)
• Strong long-term energy production
• Low annual degradation rates
• 25-year performance warranties

The best solar system is not just about choosing a single panel brand — it is about proper system design and pairing the right equipment together so your system performs reliably for decades.

The best way to determine which solar panels and equipment are right for your home is through a personalized solar evaluation where we design a system based on your roof, energy usage, and long-term goals.

Let us help you design a system that is right for you and your budget.

Under California’s NEM 3.0 (Net Billing Tariff), adding a battery to your solar system can significantly increase the financial benefits of going solar. The biggest change under NEM 3.0 is that electricity exported to the grid during the middle of the day is credited at a much lower value than in previous solar programs. Because of this, the key to maximizing savings is using your solar energy in your home or storing it for later use instead of sending it to the grid.

A solar battery allows you to store excess solar energy produced during the day and use it later when electricity from PG&E is most expensive. This strategy helps homeowners avoid purchasing high-priced electricity during peak rate periods, which is where a large portion of the savings occurs.

Without a battery, excess solar energy produced in the afternoon is typically sent to the grid at a lower credit rate. With a battery, that energy can be stored and used later in the evening when electricity prices are highest.

Adding a battery to your solar system can provide several financial advantages:

• Avoid buying expensive evening electricity from PG&E during peak rate hours
• Store excess solar energy produced during the day instead of exporting it at low credit values
• Increase the amount of solar energy your home uses directly
• Reduce reliance on the utility grid
• Improve long-term protection from rising electricity rates

Batteries also add an additional benefit many homeowners value — backup power during outages. When paired with solar, a battery can keep essential appliances running during a grid outage, helping maintain comfort and security in your home.

Under NEM 3.0, the combination of solar and battery storage allows homeowners to manage when and how their electricity is used. A properly designed system stores energy when solar production is high and uses that energy later when electricity costs the most.

Because every home uses electricity differently, the best way to determine the value of adding a battery is through a custom solar and battery evaluation. This allows us to analyze your energy usage, model how your system would perform under PG&E’s current rate structure, and show you the potential savings of solar with and without battery storage.

YES!

Under California’s NEM 3.0 (Net Billing Tariff), batteries can increase the financial value of a solar system by allowing homeowners to store solar energy and use it when electricity is most expensive. While solar panels alone will still reduce your electricity bill, adding a battery can help maximize those savings by changing when and how your solar energy is used.

A battery allows your home to store excess solar energy produced during the day and use that stored energy later, helping you avoid buying expensive electricity during peak rate periods.

Because batteries typically cost between $10,000 and $20,000 depending on capacity and installation, homeowners often want to understand how long it takes for the battery to pay for itself.

The return on investment for a battery depends on several factors, including:

• Your electricity usage patterns
• Your PG&E rate plan
• How much solar energy your system produces
• The size of the battery installed
• Future electricity rate increases

In many cases, batteries are expected to provide a financial return over 10–15 years, while most modern battery systems carry 10–15 year warranties and may continue operating beyond that period.

It is also important to consider that utility electricity rates in California have historically increased over time. As electricity prices rise, the value of stored solar energy increases as well, which can shorten the effective payback period of a battery.

For some homeowners, the decision to add a battery is based purely on financial savings. For others, the combination of long-term savings, protection from rising utility rates, and backup power during outages makes battery storage a valuable addition to their solar system.

The best way to determine whether a battery makes financial sense for your home is through a personalized solar and battery analysis. This allows us to model how your system would perform under PG&E’s current rate structure and compare solar with and without battery storage.

Several high-quality home batteries are available today, and most solar installation companies offer a few trusted options rather than just one. Common systems include batteries from Tesla, Enphase, EcoFlow, and Franklin, each designed to store solar energy, provide backup power during outages, and help homeowners use electricity more efficiently.

The most popular battery system for many East Bay homeowners is the Tesla Powerwall, which has become one of the most widely installed home energy storage systems. One reason for its popularity is its strong combination of storage capacity and power output. A single Tesla Powerwall stores about 13.5 kWh of energy and can deliver high output power capable of running multiple appliances at once. 

Other high-quality options include:

• Enphase IQ Batteries – Designed to work seamlessly with Enphase microinverter solar systems and known for modular flexibility and strong monitoring capabilities.
• Franklin Home Power (aPower) – A powerful whole-home battery system with strong output capability and expandable storage. 
• EcoFlow home batteries – A newer modular energy storage platform that can scale to large capacities for homes seeking greater energy independence. 

Each of these systems stores solar energy during the day so it can be used later in the evening or during a power outage.

Whole-Home Backup vs Partial Backup

Home batteries can be designed for either partial backup or whole-home backup, depending on how much energy storage you install.

Partial backup systems focus on keeping the most important appliances running during an outage. These often include:

• Refrigerators
• Lights
• Internet and electronics
• Garage doors
• Medical devices

With partial backup, homeowners typically install one battery to support essential circuits.

Whole-home backup, on the other hand, is designed to power nearly everything in the home, including:

• Air conditioning systems
• Electric appliances
• Laundry equipment
• Kitchen appliances
• EV charging (depending on system size)

Whole-home systems require more storage capacity because the average U.S. household uses roughly 25–30 kWh of electricity per day. During hot summer months, many Contra Costa homeowners use double or triple that amount per day. 

How Many Batteries Do You Need?

The number of batteries needed depends on your home’s energy usage and whether you want partial or whole-home backup.

Typical configurations include:

• 1 battery – Essential backup circuits and evening energy savings
• 2 batteries – Balanced solution for many homes and moderate backup capability
• 3–4+ batteries – Whole-home backup for larger homes or high energy usage 

For example, two Tesla Powerwalls provide about 27 kWh of stored energy, which is often enough to power many homes overnight when combined with daytime solar production. When solar panels are paired with batteries, the solar system can continue producing electricity during the day, powering the home while simultaneously recharging the batteries for use later. 

Choosing the Right Battery System

The best battery system for your home depends on several factors:

• Your daily energy usage
• Whether you want partial or whole-home backup
• Your solar system size
• Available installation space
• Your budget and long-term energy goals

A properly designed solar and battery system will determine the right battery type and the number of batteries needed to maximize energy savings and backup protection.

The best way to determine which battery system is right for your home is through a custom solar and battery evaluation where we analyze your energy usage and design the ideal system for your needs.

Request your Free Solar & Battery Energy Evaluation to see which battery system is best for your home.

The number of batteries a home needs depends on how much solar energy you want to save for nighttime use, how much electricity your home uses after the sun goes down, and whether you also want backup power during outages. In many cases, a good starting point is to size battery storage based on the amount of solar production you want to shift from daytime into the evening. As a general rule, for every 5 kW of solar, a minimum of 10 kWh of battery storage is often recommended if your goal is to capture a meaningful portion of your daytime solar production and use it at night.

That starting point works well for many homeowners, but the right battery size is not just about today’s energy needs. Batteries slowly lose capacity over time, so it is important to design the system with long-term performance in mind. A battery that meets your needs today may store less usable energy years from now, which is why many homeowners choose to install slightly more storage upfront. This can help preserve the long-term value of the system and allow it to continue delivering strong savings over many years.

If your main goal is simply to shift solar energy into the evening and reduce how much electricity you buy from PG&E at night, the battery system can often be sized around your nighttime usage. But if you also want backup power during outages, additional battery storage is usually needed. Backup power requires enough stored energy not only to cover evening usage, but also to keep important appliances and circuits running when the grid is down.

A simple way to think about it is:

• 1 battery may be enough for modest nighttime savings or limited essential backup
• 2 batteries is often a strong fit for greater evening energy use and better outage protection
• 3 or more batteries may be needed for larger homes, high nighttime usage, or whole-home backup goals

If you want to back up only a few essential items — like lights, refrigeration, internet, and some outlets — fewer batteries may be needed. If you want to keep more of the home running during an outage, such as air conditioning, larger kitchen loads, laundry equipment, or well pumps, then additional battery storage is usually required.

The best battery design comes down to three key questions: 

1. How much solar energy do you want to save for nighttime use? 
2. How much power do you use after sunset? 
3. And, how much of the home do you want backed up during an outage? 

When those questions are answered correctly, the system can be designed to maximize both monthly savings and long-term performance.

The best way to determine how many batteries your home needs is with a personalized solar and battery energy evaluation. That allows us to review your energy usage, your solar system size, your backup goals, and show you the right battery configuration for both savings and peace of mind.

Most modern home energy storage batteries are designed to last 10–15 years. Over time, all batteries slowly lose some of their ability to store energy. This is called degradation and is a normal part of battery chemistry. Even after 10 years, most batteries are still operating, but they typically store 70–80% of their original capacity.

The lifespan of a battery depends on several factors, including how often it cycles (charges and discharges), the temperature of the installation environment, and how well the system was designed. A properly designed solar and battery system that cycles daily can help maximize performance and longevity.

Typical factors that influence battery lifespan include:

• Number of charge and discharge cycles
• Heat exposure and installation location
• Overall system design and usage patterns
• Quality of the equipment and installation

Even with high-quality equipment, most batteries will eventually need to be replaced during the 25–30 year lifespan of a solar system.

What Happens When a Battery Needs Replacement?

Without extended protection, replacing a home battery can be expensive. Depending on the brand and labor required, battery replacement costs can range from $8,000 to $15,000 or more in the future.

Because solar systems are designed to produce power for decades, it is very likely that a homeowner will need at least one battery replacement over the life of the system.

How Solar Insure Can Provide a Replacement Battery at No Cost

The Solar Insure SI-30 Warranty provides 30 years of monitoring and protection for your solar energy system. If a covered component fails during that time, Solar Insure coordinates the repair or replacement (1 time replacement) and covers both the equipment and labor.

This protection provides several important benefits:

• Continuous system monitoring that detects performance issues early
• Parts and labor coverage, not just the equipment
• Battery replacement protection if a covered battery fails (less than 50% of original storage capacity)
• Long-term system protection for up to 30 years

If a battery stops working during the coverage period or goes below 50% of original storage capacity, Solar Insure will cover the cost of the replacement battery and the labor required to install it, helping homeowners avoid a large out-of-pocket expense.

Yes. Most modern home energy storage systems can be charged from the electrical grid as well as from solar panels. This capability allows homeowners to take advantage of lower electricity prices during off-peak hours and store that energy for use when electricity is more expensive.

Under California’s current utility structure, especially with time-of-use (TOU) electricity rates, power prices change throughout the day. Electricity is typically cheaper late at night and early in the morning, while the most expensive rates occur in the evening when demand is highest.

Charging a battery from the grid allows homeowners to store electricity when rates are low and use that stored energy later when rates are higher.

Key benefits of grid charging include:

• Time-of-use savings – store energy during cheaper off-peak hours and use it during expensive evening peak hours
• Energy security – keep the battery charged in case of a power outage
• Greater system flexibility – the battery can be charged even on cloudy days when solar production may be lower

For many homeowners, the primary purpose of the battery is still to store excess solar energy produced during the day and use that energy at night when the sun is not shining. However, the option to charge from the grid can provide an additional layer of flexibility depending on the system configuration and utility rules.

Some battery systems allow homeowners or installers to program when grid charging occurs so the battery automatically charges during the most cost-effective hours.

In California, the ability to charge from the grid can vary depending on utility policies and system settings, so the battery and inverter must be configured correctly during installation. A properly designed solar and battery system ensures the battery operates in the most efficient way to maximize long-term savings.

The average time from when you order your solar system to your installation date is about 4-6 weeks. After the solar panels are installed, it typically takes a few more weeks before the utility company grants permission to operate (PTO).

A few things that add more time to a solar project being installed are roofing, electric upgrades and city permits/inspections. Time added…

• If you work with a roofing company that is a partner of the solar installation company, it may not add much time to the installation date of the solar panels. They will install the roof while the solar design and city permits are being done. 
• Some electrical upgrades like a main panel upgrade can added 3-6 weeks to the project. The amount of extra time will depend on your local utility company as they will need to approve the main panel upgrade and schedule to run power lines to your home to accommodate the extra power needed. 
• Most cities will process solar permits within a week or two. However there are some cities that take 4-6 weeks to issue a permit. After the solar panels are installed the city will send an Inspector to check out the job and approve the work. This is normally just a week after installation, but some cities do get backed up and take several weeks to inspect a job. 

PATIENCE NEEDED! Once the solar panels are installed, be prepared that it will often take as long for you to receive permission to operate from your utility company, as it did from the time you ordered your solar system to the installation date. Utility companies are not highly incentivized to ”lose” a paying customer… so it may takes a bit longer than expected. 

BUT SMILE you are so close to being independent from your utility company and soon you’ll no longer be experiencing their electric rate increases. Savings are about to start filling your bank account. 

The average cost to have a solar system installed in California is about $30,000. It typically costs between $9,000-$13,000 to add battery backup power. Keep in mind if you pay cash or finance the project you will receive a 20-40% Federal Tax Credit to help pay for your solar system. 

Over 80% of the solar systems installed in California are done with a ZERO DOWN option. This is either through the ownership model of financing, a power purchase agreement or by leasing a solar system. 

These multiple options make switching to solar affordable for the large majority of homeowners in California.