Powerwall vs. V2G: Why Your Home Battery Beats Your EV’s Side Hustle

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Battery tech is advancing, costs are falling, and these little powerhouses are finding more applications. One of the many things you can do with batteries now is provide backup power to your home. There are two primary ways that you can do this: one, with dedicated home energy storage batteries, or two, with an electric vehicle (EV) that supports vehicle-to-home (V2H). Both home batteries and V2H keep the lights on when the grid goes kaput, but not exactly in the same way; each method has pros and cons.

In this post, we're going to compare home batteries and V2H EVs. Two examples of a home battery system are the Tesla Powerwall and the FranklinWH aPower 2 battery. Two examples of a vehicle-to-home (V2H) EV are the Tesla Cybertruck with Powershare and the Ford F150 Lightning with its V2H gear.

Home energy storage battery systems are stationary (usually mounted in your garage or the shady side of the house). They store energy for use during an outage or for electricity cost optimization. They’re the dependable, stay-at-home parent of energy solutions. These batteries can be charged up by solar, the grid, or a combination of both.

V2H systems, like the Cybertruck’s Powershare or the Ford F-150 Lightning Intelligent Backup Power system, let your electric vehicle (EV) power your home during outages. The Cybertruck has a 123 kWh battery pack (equivalent to ~nine Powerwalls) and can power a home for three to four days. However, it requires a $595 Universal Wall Connector, $1,800 Gateway, and a transfer switch. Similarly, the Ford F-150 Lightning extended-range comes in with an impressive 131 kWh pack and V2H gear will run you $3,895.

Degradation

The Achilles’ heel of V2H is battery degradation. Extra charge-discharge cycles from daily load shifting wear down your truck’s battery faster than Netflix cancels shows after the second season. When we have million-mile battery technology, this won't be an issue, but today it's a reality.

Home batteries are designed for frequent cycling and shrug off this wear like a marathon runner. This makes them ideal for grid shifting with time-of-use (TOU) pricing; charging during cheap off-peak hours and discharging during pricey peaks saves you money faster than a coupon-clipping grandparent. And if home batteries do degrade, it doesn't mean that you'll come up a couple of miles short of your next charging stop like it would in an EV.

Your EV battery is made to help you get from A to B. If it's also a 5-day-a-week workhorse for the grid, that comes at a cost of additional degradation. Battery tech may soon advance to the point where we have million-mile battery packs, allowing them to be cycled as often as needed. Until then, degradation is a real concern. This makes home batteries the practical choice today, offering reliability and savings while letting your electric truck stick to hauling and dazzling onlookers with its stainless steel swagger.

Cost

Home batteries, like a Powerwall, are not cheap (~$12,000+ installed), but they offer daily utility and savings through TOU peak-shaving and virtual power plant (VPP) programs, where utilities pay to tap your battery during peak demand. V2H systems, including Ford's and Tesla's, currently miss out on VPPs participation because your vehicle might be cruising down the road or parked at work when the grid needs it. Notably, EVs today can support vehicle-to-load (V2L) or vehicle-to-home (V2H), but none of today's EVs in the US support vehicle-to-grid (V2G) capability, further limiting their role in VPP events.

Wrapping Up

Feature	Home Energy Storage (e.g., Powerwall)	V2H (e.g., Powershare)
Primary Use	Daily load shifting, outage protection	Emergency power, off-grid support
Battery Degradation	Designed for frequent cycling	Accelerated wear from extra cycles
Equipment Cost	~$12,000 (installed, depending on size)	~$2,400 (hardware) + a compatible EV ($80,000+)
VPP Eligibility	Common, utility incentives available	Rare, limited by vehicle availability and features
Daily Savings Potential	High (TOU optimization)	Low (emergency-focused)

In summary, an electric truck with V2H is a beast for emergency power, but home batteries are the reliable workhorses. Home batteries save you money and stress on the daily. Unless you’re set on making your Cybertruck the Swiss Army knife of your garage, a home battery is the smarter bet for now, and you've always got those outlets on the Cybertruck or F150 Lightning if you need them.