As part of our 2024 Energy Storage System Buyer’s Guide, we asked ESS and battery suppliers what myths needed busted in energy storage. Here is what they had to say.
Myth: Lithium-ion is the best fit for stationary ESS
Brad Dore, Senior Director of Marketing, EnerVenue.
“The perception that li-ion is the best fit for stationary energy storage applications is a myth that deserves increasing scrutiny as other technologies emerge. One of the most significant drawbacks of lithium-ion batteries in stationary applications is their limited lifespan. Li-ion batteries will degrade relatively quickly, sometimes as early as 2,000 cycles. For stationary energy storage—where longevity is generally more crucial than non-stationary use cases—this degradation can become a significant issue that necessitates costly and relatively frequent replacements.
“Lithium-ion batteries are also prone to thermal runaway and the risk of fire in stationary storage applications. The same energy density that makes li-ion so ideal for portable devices becomes a liability in stationary applications. The consequences of a fire in an energy storage facility can be catastrophic to both property and in terms of safety and environmental concerns.
“Another myth surrounding lithium-ion batteries for stationary energy storage is the batteries’ environmental friendliness. While they may appear eco-friendly due to being synonymous with electric vehicles, the production of lithium-ion batteries involves resource-intensive mining and manufacturing processes. The extraction of lithium can have detrimental effects on local ecosystems and water resources. Additionally, recycling lithium-ion batteries is challenging and can lead to the release of harmful substances into the environment.
“Furthermore, the increasing demand for lithium-ion batteries—driven by the growth of the EV market—has led to a shortage of lithium resources. This scarcity has resulted in rising costs, making lithium-ion batteries less economically viable for stationary energy storage projects. In contrast, emerging stationary energy storage alternatives like metal-hydrogen, sodium-ion, and gravity-assisted battery systems offer some promising new solutions to these challenges. They’re showing longer lifespans, enhanced safety features, and reduced environmental impacts.”
Myth: Bigger is better!
Magnus Asbo, senior director of technical marketing, SolarEdge Technologies
When it comes to energy storage, size isn’t the most important factor to consider. While capacity matters, homeowners and installers should focus on several key aspects to ensure they choose the right battery system. Here’s why bigger isn’t always better:
1. Power. Power is what determines how many devices as well as the size of appliances a battery can backup – even if a battery can store a lot of power, it is more important that it be able to produce enough power to keep up with a homeowners needs.
2. Efficiency Is Key. High capacity is only useful if the battery is efficient – in some cases, larger batteries need extra capacity just to compensate for their lower efficiency. It’s important to make sure every stored watt counts.
3. Prioritize Safety and Build Quality. Is the battery built by a reputable manufacturer known for quality? Has it been rigorously tested to meet safety standards like UL9540A? Does it’s warranty last a minimum of 10 years without hidden cycle count or discharge clauses? Ensuring that your chosen battery is built to last and is secure is crucial for long-term satisfaction.
4. Ensure the Battery is Part of an Ecosystem. It’s crucial to choose a battery and inverter from the same manufacturer that seamlessly work together as part of an integrated energy ecosystem. This ensures superior support, enhanced reliability, improved efficiency, and an overall superior battery experience.
Myth: Batteries are too expensive!
Vinnie Campo, cofounder and CEO, Haven Energy
“The biggest myth we come across is that installing a home battery system is prohibitively expensive. Home battery prices have fallen by as much as 89% in the last decade and are projected to nearly halve again by 2030. Homeowners can now claim a 30% federal tax credit for installing energy storage and potentially up to $6500 more dollars in rebates for electrical system upgrades, all thanks to the Inflation Reduction Act.
At the state level, homeowners can further reduce the cost of a new home battery system. California homeowners can take advantage of the state’s Self-Generation Incentive Program (SGIP) which allows them to take $1,750 off the cost of a one-battery system (for eligible households). For a two-battery system, they would be able to take $3,500 off.
Once installed, batteries can also save homeowners money. In areas that offer time-of-use pricing plans (most of California), homeowners can charge their battery when electricity is cheap and discharge the battery when it becomes more expensive. This reduces electricity bills $2 – 5 dollars per day, every single day. A single installed battery can save someone $800-$1600/year on electricity bills, reducing cost of ownership of the battery significantly.
Lastly, homeowners can enroll in a virtual power plant (VPP), which gives them a way to earn extra income by participating in demand response programs. Haven’s VPP is part of California’s recently approved incentivization program for participating in grid services programs. When electricity demand is high and the grid is struggling, Haven can draw from their customers’ batteries – exporting stored energy to help rebalance the grid – and paying them at least $125 per year in return. As demand response programs improve the grid’s reliability, we expect incentives for participation to increase and grow.”
Myth: Lithium isn’t safe
Sequoya Cross, VP of energy storage, Briggs & Stratton Energy Solutions
“Not all Lithium batteries are the same, and as more stable chemistries have come online, Lithium batteries have actually become safer. Utilizing Lithium Iron Phosphate (LiFePO4) chemistry delivers more efficient, safer and reliable energy storage. The LiFePO4 chemistry eliminates cobalt, a conflict mineral used in other Lithium-Ion batteries, reducing the risk of thermal runaway with fire propagation, operating temperature constraints and toxic coolants.
“Also, just because a system may say it has completed UL9540A testing it doesn’t always mean there aren’t risks associated with different products. They need to look deeper at the actual results of the safety tests to understand if the products they are working with are truly safe. A resource for installers looking to do this research is the UL database of manufacturers that have shared their testing reports openly.”
Myth: Whole home backup is too complex
Alex Bazhinov, founder and COO, Lumin
Several myths in energy storage are tied to how smart electrical panel solutions can revolutionize your energy storage experience.
Myth: You need multiple batteries for whole-home backup. While the number of batteries typically dictates how many circuits you can access in a traditional battery backup setup, some smart panels can unlock access to all your circuits during an outage by automatically keeping you within your power threshold, even on one battery.
Myth: Hardware compatibility and installation complexity are major barriers. Fact: Smart panels can eliminate compatibility concerns if they have a hardware-agnostic design. A retrofit-ready design seamlessly integrates with any load center or battery.
Myth: Maximizing solar and storage ROI is complicated. Highly intelligent smart panels with scheduling capabilities can optimize your solar and storage return on investment (ROI). Scheduled automations can significantly accelerate your ROI by strategically shifting loads to avoid peak time-of-use rates or maximize export incentives under NEM 3.0.
Myth: It’s all about costs per kWh
Michael Menendez, head of product, Blue Planet Energy
“I’ve seen a troubling trend emerge in the industry where people are pricing their systems based on the cost per kilowatt hour without thinking about the cost of ownership across the lifetime of the system. There are many powerful systems out there that are simply not built to last.
While everyone is debating the upfront cost of a system, they are not factoring in the longevity, quality, or expandability of an energy storage system. For example, you can have a product that is $10 per kilowatt hour, which is great, but if it only lasts for a few years, then you’re going to have to remove the system, replace it, pay for labor again, and then it ends up being recycled or even worse in a landfill, driving up the carbon footprint of the system and defeating the purpose.”
Smaller C&I projects aren’t economically viable
John Cromer, senior technical manager, Sol-Ark
“Batteries are changing the way we think about solar. No longer is it necessary to cover the entire roof with solar panels to have a viable project. In fact, commercial solar plus storage projects often have a reverse economies of scale, where the smaller project can be the more cost-effective one. This is because commercial facilities are more likely to have peak vs. off-peak rate structures. By offsetting only the peak rate, businesses can save a significant amount of money. This is inherently more cost-effective than also reducing the off-peak rate, as the off-peak rate is already relatively low.
In other words, it can be very cost-effective to help the end-user access cheaper off-peak energy while avoiding expensive peak use, instead of offsetting 100% of their bill. This represents a positive path for utility policy as the high cost of energy risk is decreased, and the low cost base generation is increased. The customer wins as they achieve a multiplier effect. The solar array may only generate 25% of the site energy use, but the electric bill may reduce by half. And the customer also gains access to cheaper grid provided electricity.
This means that a successful project of the future might look more like a smaller solar array and larger battery bank. The solar installers who realize that batteries are what provide the most value to the customer are the ones who will see their business continue to grow as net-metering policies are being scaled back.”
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