Powering chiller systems with BESS: cutting fuel, emissions and generator size
What is BESS, and how does it work with a chiller?
A battery energy storage system, or BESS, stores electrical energy and releases it on demand. Paired with a chiller, it sits between the generator and the compressor, absorbing load spikes so the generator can run at a steady, efficient rate instead of chasing every peak.
For more on how BESS works more broadly, read our guide to battery energy storage systems.
The real challenges of powering industrial chillers
Industrial chillers keep manufacturing lines, cold stores, data centres and events running, but powering them reliably isn't straightforward.
High start-up currents
Chiller compressors draw a huge surge of current when they start, often several times their normal running current. That surge can push a generator or grid connection to its limit, and the usual fix is to oversize the generator just to cope with a few seconds of start-up.
Variable, unpredictable demand
Chiller loads rarely sit still. As demand fluctuates, an oversized generator ends up running well below its efficient operating range for most of the job, burning more fuel per kilowatt than it should.
Limited grid capacity
New builds, remote sites and temporary events often come with restricted mains supply. When the grid can't cover peak demand, cooling is the first thing at risk.
Mounting pressure to cut emissions
Reliable cooling used to be enough on its own. Now you're expected to deliver it with less fuel, less carbon and less noise, without compromising on uptime.
How battery energy storage solves each of these problems
BESS doesn't replace the generator. It works alongside it, and that changes the economics of the whole setup.
Smoothing compressor start-up surges
The battery absorbs the inrush current a compressor demands at start-up, so the generator no longer needs to be sized for a spike it only sees for a few seconds. That's often enough to specify a smaller generator for the same chiller.
Keeping generators in their efficiency sweet spot
Diesel generators run most efficiently at 70 to 90% load. BESS smooths the fluctuating chiller load so the generator can sit in that range instead of swinging between under and overload, which is where most of the fuel savings come from.
Adding resilience without adding diesel
Because BESS delivers instant power, it backs up the system against grid instability or a supply interruption, without needing a bigger, noisier diesel setup running in reserve.
Cutting fuel and emissions at the same time
Less generator runtime means less fuel burnt and less CO2 released, without asking anyone to compromise on cooling performance.