If you’ve been looking to buy a battery to store renewable energy you might have noticed something strange — the shelves are nearly empty. The energy storage market, which up until recently had more than a half-dozen varieties to choose from, has gone through a bottleneck and drastically reduced in size, leaving only two competitors with any product left to sell.
The reasons for the shortage are no mystery. With the portent of next year’s tariffs looming on the horizon and a narrowing window on government incentives, 2018 saw a rush to purchase energy storage units, such as the sonnenBatterie eco and LG Chem RESU, which were selling at record low prices.
Now that the dust has begun to settle, the only two companies left standing are the Tesla Powerwall and the Blue Ion 2.0. The first might not come as a shock. The Tesla Powerwall is one product in a suite of Elon Musk’s renewable innovations, which enjoyed the advantage of first mover in the marketplace back in 2015. Tesla is also a larger company, and has the industrial infrastructure to create enough supply to satisfy market demand.
The Blue Ion 2.0 was a bit later to the energy storage game. Reasons for its available stock most likely have to do with the fact that its founder, Henk Rogers, also happens to be the innovator of the pop-video game franchise Tetris, affording the company with enough startup capital to create more products than its competitors. Another possible reason for its availability is its price-point. Costing nearly twice the amount of a Powerwall, the Blue Ion 2.0 might seem more pricey at first glance. However, a side by side comparison of the two products reveals some noteworthy differences that might help justify the higher price tag for consumers shopping for the best deal.
Powerwall runs on lithium manganese cobalt batteries, the same sort of stuff that’s used for power tools and powertrains on vehicles. Because the battery is made partially of manganese, the raw material cost is lower than other options as cobalt can be expensive.
BLUE ION 2.0
Sony’s lithium ferrous phosphate batteries, which power the Blue Ion 2.0, are a high-end battery compound allowing for more efficient power storage. These batteries aren’t plagued by the same thermal runaway that traditional energy storage units are. The company claims its batteries are safer than Tesla’s, with the difference in material quality affecting all its other performance facets down the line.
It takes approximately 2 hours to charge a Powerwall using either peak sunlight or grid power. The battery has a leg up on the majority of its competitors, sporting a 100% Depth of Discharge (DOD), which means it can dump all the energy its storing and doesn’t have a stop mechanism in place if a home pulls past a certain amount.
BLUE ION 2.0
Like the Powerwall, the Blue Ion 2.0 also has an impressive 100% DOD. Unlike the Powerwall, the Blue Ion 2.0 can fully charge in half the time, reaching a full charge in an hour. Known as the Charge Rate (C), the Blue Ion 2.0 has a 1C versus the Powerwalls ½ C, which takes twice as long to fill up.
When it comes to a home energy storage unit size matters, or rather the lack thereof. Without a doubt, the Powerwall is one of the sleekest looking batteries on the market, with an L x W x D: 45.3” x29.7” x 6.1”. A single unit has a 7kW peak / 5kW continuous power capacity.
BLUE ION 2.0
The Blue Ion 2.0 is more bulky and measures in at 24” x 24” x 39” (L x W x D). The reason for its bulky proportions has to do with the way the unit is built. Rather than have one power core, the Blue Ion 2.0 is made up of multiple cores that are synchronized with a Super Battery Management Unit (BMU). The difference is akin to have a solar power system with a single inverter or one with micro inverters. Having a BMU increases the battery’s efficiency, making it so that one Blue Ion 2.0 is roughly the power storage equivalent of two Powerwalls.
COST & WARRANTY
To power a 2,200 sq ft home, it is estimated to take about 2 Powerwalls and cost $13,500 not including installation. Tesla’s warranty is good for 10 years, which is approximately 2,800 charge cycles per battery, and will replace the battery within that time if it operates at less than 70%.
BLUE ION 2.0
It is likely that a single 8kWh energy storage unit would be sufficient to power a 2,200 sq ft home thanks to its power regulating BMU and more hearty battery compounds. The 2 unit will run approximately $25,900, not including installation and has a warranty that is good for up to 15 years, or approximately 8,000 charge cycles.
THE FINAL VERDICT
Every home is different, and that means there’s definitely one choice over another that would suit yours better. Tesla Powerwalls are clearly designed for homes in a more urban setting, with a constant feed into the grid, whereas the Blue Ion 2.0 can charge faster and power one’s electronics a bit longer without being top off by any sunlight or grid power. Ultimately, the choice comes down to what your power needs are. Solar companies such as Go Green Solar are always eager to help people figure this equation out, and are a great free resource of expert advice.