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Homeowner converts used BMW car battery into emergency power source

"That's a lot of stored power!"

A metallic panel on a red wall, surrounded by equipment including a used EV battery.

Photo Credit: Reddit

Upgrading your home with solar panels and battery storage is one of the tried and tested methods for saving money on home energy, preparing for power outages, and even cutting ties with power companies. 

One homeowner recently took to Reddit to share how they transformed a BMW i3 battery into a home backup energy solution. The original poster had the comment section intrigued after sharing an image of the large battery system.

A full view of the repurposed EV battery setup.
Photo Credit: Reddit

In the comments, the OP explained they used an inverter and battery emulator to pair the electric vehicle battery with their solar panels. The total cost of the project was $1,176. "I think this is the cheapest way for sure to get a large home battery!" the OP added.

They aren't the only one reaping the benefits of cheap at-home energy. With some solar owners seeing thousands of dollars in savings on their bills over the years, panels and batteries are becoming popular upgrades across the United States.


Want to go solar but not sure who to trust? EnergySage has your back with free and transparent quotes from fully vetted providers in your area.

To get started, just answer a few questions about your home — no phone number required. Within a day or two, EnergySage will email you the best options for your needs, and their expert advisers can help you compare quotes and pick a winner.

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If you're curious about how solar panels can transform your home energy, connect with the experts at EnergySage. Its free tools can help you get quick installation estimates and compare quotes.

While some commenters had valid safety concerns, which the OP addressed, others offered support for the DIY endeavor.

"Does anyone have a business doing this yet?" one user wrote. "I'm a huge fan of reusing electronics like this, and also it seems like an economical way to get a massive home battery backup."

Another said: "This is simply awesome. I never knew. That's a lot of stored power!"

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Want to go solar but not sure who to trust? EnergySage has your back with free and transparent quotes from fully vetted providers that can help you save as much as $10k on installation.

To get started, just answer a few questions about your home — no phone number required. Within a day or two, EnergySage will email you the best local options for your needs, and their expert advisers can help you compare quotes and pick a winner.

While this homeowner chose a DIY approach, many find it easier to work with trusted partners to find the best solar panels for their homes and budgets. Homeowners using free comparison tools can save up to $10,000 on solar purchases and installations.

EnergySage also offers a helpful mapping tool that shows you, at the state level, the average cost of home solar and available incentives. It ensures you lock in the best price for rooftop panels and snag all the incentives you can.

Plus, if you're looking for home battery solutions like this homeowner, EnergySage can help you with competitive installation estimates and information on storage options. If you're concerned about power outages or rising energy costs, or looking to cut ties with the grid entirely, a home battery backup could be a good fit. 

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