Solar Energy For ADUs: Everything You Need To Know

An ADU with solar panels on top

Are you considering solar panels for your ADU (Accessory Dwelling Unit)? 

Solar energy can significantly reduce energy costs and increase property value. Let’s explore everything you need to know about integrating solar power into your ADU.

Why Install Solar Panels on ADUs?

Well, first of all, you may not have a choice in installing solar energy on your ADU, but more on that shortly.

In practical terms, solar panels are not only environmentally friendly but also cost-effective. You’ll save money in the long run and also help the environment, so it makes a lot of sense in theory to have solar panels on your ADU.

There are also tax credits available if you qualify.

California’s Solar Requirements for ADUs

In California, new ADUs must comply with Title 24 energy standards

These regs basically say that ADUs need to include energy-efficient features like solar panels to ‘reduce greenhouse gas emissions and promote sustainability.’

These requirements are part of California’s broader goal to increase renewable energy use and reduce reliance on fossil fuels, with the goal of net zero emissions by 2045.

Title 24 is reviewed every three years, with the latest revisions released in 2023.

Title 24 2023 Revisions 

All ADUs built for single-family homes must have solar provisions, and solar energy generation must be enough to offset the in-laws’ annual energy consumption.

This applies to permits sent after 1 January 2020 or ADUs constructed built after 31 December 2019.

Exceptions To the Rule

There are some exceptions where solar power may not be required.

Greater San Diego 

Small ADUs (less than 620 sq ft) may be exempt from solar requirements in some areas of Greater San Diego. However, once your ADU is over 1,125 sq ft, it will require solar, no matter the location.

Climate Zones

The solar requirement also relies on the climate zone, with units above a certain threshold in a climate zone requiring solar and others not.

This essentially means that a calculation is required to figure out whether your specific ADU requires solar or not, and this is based on whether the minimum size based on section 150.1(c)14 is less than 1.8Kw.

Additions

Some new home additions may not qualify as new construction and will, therefore, not require solar.

Working with a specialist ADU builder or energy installer will make determining whether you need solar much easier.

Benefits of Solar Panels for ADUs

Solar panels are super beneficial for ADUs.

The most obvious one is with lowering your energy bills, with average savings of a whopping $50,000 over 25 years

Another key benefit is solar panels lower carbon footprint, which is a huge benefit if you’re environmentally concious.

Additionally, generating your own electricity provides energy independence, making you less reliant on the grid. Finally, homes with solar panels tend to sell faster and at higher prices, thereby increasing property value.

Factors to Consider

Installing solar panels is a fairly straightforward process, but there are a couple of things to keep in mind.

The main one is actually having enough room for the panels themselves – solar panels are pretty big, and need a fair bit of space.

If you’re short for space, you may have no option but to use other space on your property.

Assessing your ADU’s energy consumption helps determine the size of the solar system needed. While solar panels can be a significant upfront investment (usually $15,000 to $25,000), various incentives and financing options can help offset the costs, making the installation more affordable in the long run.

Installation Process

The installation process shouldn’t be much of a hassle.

First of all, you’ll have a professional come out and do a site assessment. This is basically a quick check for what type of solar panel would work best for your ADU, and where they could be palced.

This is followed by the design and permitting phase, where a custom system design is created, and the necessary permits are obtained. The actual installation of the solar panels usually takes one to three days, depending on the system’s complexity. 

Finally, the system undergoes inspection and activation, connecting it to the grid and ensuring it operates efficiently.

Maintenance and Longevity

Solar panels require minimal maintenance, making them a convenient choice for homeowners. Regularly cleaning the panels and ensuring no debris or shade obstructs them will maintain their efficiency. 

Most solar panels come with warranties of 20-25 years, guaranteeing their performance and durability. With proper care, these panels can continue to generate electricity effectively for decades, providing a reliable source of renewable energy for your ADU.

Tax Credits

In California, there is an investment tax credit, or federal solar tax credit, which is a 30% federal residential solar energy tax credit for solar installations.

This means you can submit a 30% tax credit if you qualify, with the requirements available on the Office of Energy Efficiency and Renewable Energy.

These include things like owning the solar system, paying federal taxes, and more. They also exclude expansions of existing systems.

FAQs

Do I need solar panels on my ADU? 

In California, new ADUs must meet Title 24 energy standards, which often includes solar panel installation. 

There are exceptions to the rule, though, including climate zones, size, and addition considerations.

What is the lifespan of solar panels? 

Most solar panels come with warranties of 20-25 years and can last even longer with proper maintenance.

So There You Have It

Integrating solar panels into your ADU is a smart move for both financial and environmental reasons. 

By understanding the requirements, benefits, and installation process, you can make an informed decision that enhances your property and contributes to a sustainable future. 

For more information, consult with local solar energy experts and explore available incentives to make the most of your investment.

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