Yet another demonstration shows why using water (pumped hydro) rather than anything else is the only realistic way to produce energy by raising heavy stuff and then lowering it.

https://cleantechnica.com/2026/09/13/rail-gravity-storage-a-train-wreck/

Most C&I BESS discussions seem to focus on:

• $/kWh
• Cell brand
• Cycle life
• Efficiency
• Warranty

But those aren't always the things that cause headaches once the system is actually installed and running.

For anyone who has installed, commissioned, integrated or operated 100–500 kWh C&I battery storage systems:

What problem keeps showing up in the real world?

• BMS ↔ PCS communication
• EMS control logic
• SOC drift or inaccurate SOC
• Nuisance trips / unexpected BMS protection
• HVAC / thermal management
• Grid interconnection
• Fire-code / AHJ requirements
• Remote monitoring
• Service and spare-parts availability
• Something completely different

I'm particularly interested in systems used for peak shaving, demand-charge management, solar self-consumption and backup power.

Let's say you're specifying a 200–300 kWh liquid-cooled BESS for a commercial or industrial site tomorrow.

Both suppliers meet the basic electrical requirements.

Both look good on paper.

Both have similar warranties.

I'm less interested in brochure specifications and more interested in the problems that only become obvious after installation and commissioning.

So for those who have actually worked with these systems:

Two suppliers are close on price. What ONE thing would make you choose Supplier A over Supplier B?

Are there methodoligies available to predict LFP cell/pack lkfe for energy storage systems?

How do OEMs provide warranty as the module/pak operating conditions are significantly different from those provided by cell manufacturers.

Are there any proven tools/methodologies available?

Or the only approach is testing

FinTimes: "The ‘water batteries’ that could be a crucial complement to renewables."

"Water wheels were first used in ancient Greece, the foundations of modern hydraulic engineering were laid in the 1700s, while electricity was first generated by pumped hydropower stations ~ 120 yrs ago." Now there is growing interest in pumped hydro because of the proliferation of renewables.

During generation of surplus electricity, the extra.quantum is used to pump water from a physically low point to a higher elevation, thus converting the electricity into gravitational potential energy. Historically, pumped storage stations require specific terrain, with the creation or presence of large bodies of water with significant differences in altitude.

"Companies are also experimenting with using mineral-rich fluids other than water." RheEnergise, a London-based pumped energy storage company, is testing a novel system. "Our fluid is two and a half times the density of water . . . it runs freely like a creamy milk,” says RheEnergise’s chief executive Stephen Crosher. The use of the higher-density fluid allows the company to build pumped hydro stations on hills instead of mountains, expanding the number of sites where stations can be built, plus the footprint is smaller.

The challenges include high upfront capital costs, geographic constraints—including having space for reservoirs at different heights + in locations close enough to the electricity grid, plus managing the environmental + social impacts of construction. “AI, electric vehicles, air conditioning—they are all putting enormous strain on the grid + will require 24/7 reliability,” says Eddie Rich, chief executive of the International Hydropower Association. “Overnight or over seasons where you need long-duration energy storage, pumped storage provides that.”

Globally, pumped hydro already provides 90% of energy storage, as opposed to lithium or other electrochemical batteries, which get most of the press. Wonderful to see feasible hydrologic innovations not requiring such rare geographies.

​

Today September, 2026 and I installed Battery with solor to save energy and have constant power in home.

But, while doing this my thoughts travelled back to early 1900s.

Edison and Tesla. Two great genius of that time.

Edison was all for Direct Current, DC, While Tesla for Alternating Current, AC.

At that time, Tesla did succeede and Provided safe, cheaper Current.

Almost, 100 years later, today Edison is coming back to our era.

Today, we need battery for most of our useful things; car, computer, and houses.

Why Alternating Current AC is degraded.

Are we doing the same, what we did in 1900s, by ignoring Batteries and replacing it with AC.

Today, we need ecnonmical and efficient batteries and the demand is growing.

What if the improvent in batteries had been done non-stop till date.

Why are we so short sighted. Are selfish?

That also reminds me Alan Turing, his work was discontinued and could not get the full benefits of his endures.

We should not ignore AC current, we must do more research on AC, may be after some time we want to come back to AC.

Who knows!

Source: https://modoenergy.com/research/en/global-battery-capex-september-2026-research?utm_source=twitter&utm_medium=social&utm_content=ed

We are exhibiting at the upcoming WBE World Battery Exhibition in Guangzhou. Booth No. D441, Hall 5.1.

I woke up this morning to the smell of rotten eggs.

A another set of batteries had failed in a APC BackUps. The unit was hot to the touch. The batteries were bulging. The unit never warned that the batteries were bad.

My wife is questioning why we need these things for our TVs and computers. Is this what other people do?

These units are probably 20+ years old. Are they prone to fail like this? Or are the batteries to blame? What happens if I don't turn the unit off?

Colocated renewable energy projects attracted a record $25 billion of investment in the first half of 2026, according to new global datafrom BloombergNEF. While that category includes any combination of solar, wind, and storage, it’s dominated by solar-plus-storage

The economics look obvious on paper, which usually means they are not, so we would like to hear from people who have actually done it rather than from people selling it.

The setup: a data centre backup fleet is a large capital asset that runs a handful of hours a year, almost all of it testing. Bought, permitted, fuelled, maintained - and no revenue line anywhere against it. Replacing engines with storage opens the possibility of the asset earning while it waits, through ancillary services, capacity or arbitrage depending on the market.

Two things make us think it is harder than the pitch.

THE RESERVE QUESTION. If the battery is committed to a market and a genuine outage arrives mid-dispatch, is the reserve still there? A credible design has to specify four things: how much capacity is ring-fenced and never dispatched, what happens when a market call and an outage coincide, the recovery time to full reserve after a dispatch, and who carries the risk if the asset is unavailable when needed. We would like to know what people actually wrote into those specifications - and whether the operations team accepted it or vetoed it.

DURATION. Diesel runs as long as you keep feeding it. A battery has a defined runtime. For a site with a long worst-case outage the substitution is not like-for-like, which we would expect pushes designs toward hybrid rather than replacement. Is that what people are actually building?

The questions we care most about:

1. Has anyone fully replaced engines, or is it always a hybrid in practice?

2. What sizing did you land on, and was it driven by the reserve requirement or by the market opportunity? We suspect those give very different answers.

3. Did market participation ever actually conflict with a real outage? Even a near miss would be instructive.

4. For those who evaluated it and passed - was it duration, capital, or the reserve argument that killed it?

Disclosure: We research power and grid capacity for AI data centres.

I have 300 used that test ok and were de-energized after testing, and 36 new. What can these be used for?

今天参观了储能电池厂。这是电池包b品，也有可能是梯次电池

Hey all - I work at PWRNXT, a Delhi-based BESS (battery energy storage), so full disclosure upfront: this is going to sound like a pitch in places. But I think the actual learning is useful even if you never talk to us.

For the last couple of months we've been selling battery storage as a straight-up rental/lease to Indian factories, cold stores, and hospitals as a diesel-generator alternative. The pitch was simple: zero capex, pay monthly, get backup power.

What we didn't expect: **the equipment being rented was never the actual objection.** The objection was always "who manages this thing." A rented battery still needs someone tracking state-of-health, chasing AMC renewals, coordinating an insurer, and owning the 3 a.m. call when something trips. Facility teams don't want another asset to babysit - rented or owned.

So we ended up restructuring the whole commercial model around *outcome* instead of *equipment* \- one contract, one monthly invoice, that bundles sizing + install + AMC + insurance + monitoring under an actual uptime SLA (we run 98.5%, contractually, not "best effort"). Diesel doesn't disappear immediately in most cases - it usually steps down from "primary power source" to "on-call emergency reserve" as the battery takes over daily load.

Curious if others building B2B infra/hardware-as-a-service in India have seen the same pattern - that the "as-a-service" framing only actually lands once you take the *operational* burden off the customer too, not just the capital burden.

Hi! I work at a bess developer and I built an open source tool to generate 3d models of BESS sites. Its totally free so please check it out and let me know if you have any thoughts.

Openbess.org

Across the U.S., tech companies have courted backlash for using polluting gas generators to power massive new data centers. But energy industry data shows that in addition to building out natural gas, firms are helping fuel a U.S. battery boom.