Battery Energy Storage Systems (BESS): What They Are, How They Work, and Why Businesses Are Investing Now
December 22, 2025
Battery Energy Storage Systems (BESS) are quickly becoming one of the most practical ways to cut energy costs, strengthen resilience, and make renewables work harder—without compromising power quality.
If you’ve seen the term “BESS” and wondered what it actually means, this guide breaks it down in plain English: what a BESS is, how it works, the key benefits, and how YorPower can now provide a complete BESS solution—working with a range of manufacturers, including Cummins.
What is a Battery Energy Storage System (BESS)?
A Battery Energy Storage System (BESS) is a technology that stores electrical energy in batteries and then releases it later when it’s needed. This stored energy can come from the grid, on-site generation (like solar), or a generator in a hybrid setup.
At a grid level, battery storage helps balance supply and demand—especially important as more wind and solar generation comes online.
At a business/site level, BESS is often used to:
- Reduce peak-time electricity costs
- Provide fast backup power (or bridge power)
- Support EV charging infrastructure
- Smooth intermittent renewables
- Reduce generator run hours and fuel burn in hybrid systems
How does a BESS work?
Think of a BESS as four systems working together:
1) The battery packs (energy storage)
Most modern BESS solutions use electrochemical batteries (commonly lithium-ion) to store energy.
2) Power conversion (inverters)
Batteries store energy as DC electricity, but most sites and the grid use AC electricity. The inverter converts DC ↔ AC so the system can charge and discharge safely and efficiently.
3) Control system / “brain” (EMS)
An Energy Management System (EMS) monitors:
- your site load (kW demand)
- grid conditions/tariffs
- renewable output (e.g., solar)
- generator status (if part of a hybrid system)
It then decides when to charge/discharge to hit your goals (cost saving, resilience, carbon reduction, etc.).
4) Safety systems (thermal management + protection)
Commercial BESS includes protection, monitoring, and thermal management designed to keep operation stable and safe—especially in containerised or outdoor installations. (Exact features vary by manufacturer.)
Common BESS applications for businesses
Peak shaving (cutting maximum demand charges)
A BESS can discharge during your highest-demand moments so your site draws less peak power from the grid—often one of the fastest ways to unlock savings.
Load shifting (using cheaper energy later)
Charge the batteries when electricity is cheaper (or when your solar is overproducing), then discharge during expensive periods.
Backup power and resilience
BESS can respond extremely fast during an outage—supporting critical loads and reducing downtime risk.
Renewables firming (making solar/wind more usable)
Battery storage allows renewable energy to be stored when it’s generated and used later, helping match production to demand.
Hybrid generator + battery systems
Pairing a BESS with a generator can reduce fuel usage and emissions by letting the generator run more efficiently—while the battery handles spikes and fast changes in load.
What are the benefits of Battery Energy Storage Systems (BESS)?
Lower energy costs
- Reduce peak demand charges
- Shift usage away from expensive tariff windows
- Increase self-consumption of on-site renewables
Better power quality and stability
BESS can react quickly to changes in load, helping smooth spikes and support more stable operation—particularly useful for sites with variable demand.
Stronger resilience and continuity
BESS can provide backup power during outages or bridge the gap while other standby systems start and stabilise.
Reduced emissions (especially in hybrid setups)
By reducing generator run hours and supporting renewables, BESS can reduce fuel consumption and emissions in many applications.
A future-ready foundation for EV charging and microgrids
As sites electrify fleets and add chargers, BESS can help manage demand and reduce costly grid upgrades—especially when combined with smart controls.
YorPower BESS solutions
YorPower now provides Battery Energy Storage System solutions for commercial and industrial users—helping you move from “we’re interested in batteries” to a working, supported system on site.
What we can deliver
Depending on your project requirements, YorPower can support:
- Site and load assessment (what you’re trying to achieve and what it will take)
- System selection (power/energy sizing, runtime goals, integration needs)
- Supply of BESS equipment from leading manufacturers
- Integration with existing infrastructure (grid connection, switchgear, generators, renewables, controls)
- Commissioning, handover, and ongoing support
