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A Dutch factory may have enough annual electricity supply but still be unable to increase its maximum grid import.
A new production line, electric boiler, heat pump or EV fleet can push the site above its contracted transport capacity.
MegSolid approaches this problem by calculating the factory’s available power envelope first. The battery is selected only after the discharge requirement, recharge window and contract restrictions are known.
RVO identifies flexible loads and battery storage as possible tools for companies affected by grid congestion, but advises companies to map their existing demand and movable loads before selecting a measure.
The battery does not create more grid capacity. It shifts available capacity from one time period to another.
Start With the Grid Capacity Gap
The first calculation is the factory’s residual power deficit.
Required BESS power = Existing load + New load − Permitted grid import + Safety margin
Illustrative example:
| Input | Value |
|---|---|
| Contracted grid import | 1,000kW |
| Existing factory load | 820kW |
| New production line | 250kW |
| Engineering margin | 50kW |
The preferred grid ceiling is:
1,000kW − 50kW = 950kW
Total production demand is:
820kW + 250kW = 1,070kW
The preliminary BESS power requirement is therefore:
1,070kW − 950kW = 120kW
This calculation establishes PCS power. It does not yet establish battery energy.
Build a 24-Hour Capacity Budget
A monthly electricity bill does not show whether the factory has enough capacity to operate and recharge a battery.
Use at least 12 months of 15-minute data to identify:
- Base load
- Process peaks
- Planned expansion
- Flexible loads
- PV generation
- BESS discharge periods
- BESS charging periods
RVO’s Flex-e guidance asks businesses to describe daily and weekly flexibility on a quarter-hour basis, including how consumption changes after the proposed measure.
The result should be a 24-hour capacity budget showing where every kW is allocated.
The BMS and EMS communication architecture must use the grid meter as the main control reference.
Calculate the Required Energy Duration
Power determines how large the PCS must be.
Duration determines how much energy the battery must deliver.
If the 120kW deficit continues for four hours:
120kW × 4 hours = 480kWh AC
The battery must provide at least 480kWh at the AC delivery boundary in this illustrative operating case.
The nominal battery capacity will need to be higher after considering:
- Usable SOC window
- Conversion losses
- Auxiliary consumption
- Temperature
- End-of-life capacity
- Operating reserve
A 500kWh nameplate battery should not automatically be treated as a system capable of delivering 480kWh AC every day.
Check the Recharge Window
Many projects pass the discharge calculation but fail the recharge calculation.
Assume the factory still consumes 860kW after the production event.
The permitted BESS charging power becomes:
1,000kW − 860kW − 50kW = 90kW
Using an illustrative charging-path efficiency of 90%, replacing 480kWh requires approximately:
480kWh ÷ 0.90 = 533kWh
At 90kW, the theoretical recharge time is:
533kWh ÷ 90kW = 5.9 hours
If the next shift begins after four hours, the battery cannot fully recover.
The hidden constraint is often charging headroom, not battery capacity.
The 90% value in this example is an engineering assumption, not a MegSolid product specification.
Move Flexible Loads First
The battery should support only the load that cannot be moved.
The factory should first review:
- EV fleet charging
- Electric boilers
- Heat pumps
- Chillers
- Air compressors
- Batch heating
Delaying a 150kW charging fleet may reduce the required BESS power by almost 150kW.
The correct sequence is:
- Separate fixed and flexible loads.
- Reschedule flexible loads.
- Recalculate the remaining deficit.
- Size the BESS for the residual requirement.
This prevents the factory from buying battery capacity to cover avoidable peaks.
Confirm the Flexible Contract
Dutch large users can enter flexible arrangements with their network operator.
Under these contracts, the company changes its consumption or generation according to available grid capacity.
Compensation or a network-charge reduction may be available, depending on the agreement.
RVO states that congestion-management contracts generally require a large-user connection above 3×80A and at least 100kW of available flexible capacity.
Signing a flexible contract does not remove a company from the waiting list for a larger connection.
Before sizing the BESS, confirm:
- Restricted time windows
- Required response power
- Activation frequency
- Response time
- Measurement method
- Non-delivery conditions
These terms directly affect the PCS rating and required SOC reserve.
Account for Capacity-Control Dispatch
Since May 2026, the Dutch capacity-control contract has largely replaced the earlier capacity-limitation contract.
The newer arrangement can require a large user to temporarily reduce or increase net electricity use. During demand congestion, a battery-equipped site may be asked to inject power instead of merely reducing consumption.
This creates a design conflict.
The battery may be expected to support:
- Factory expansion
- Network-operator dispatch
- Critical backup
- Electricity-price optimisation
These services cannot all assume that the complete battery power and SOC remain available.
Set the EMS Service Priority
The EMS should define which service receives battery capacity first.
| Priority | Service |
|---|---|
| 1 | Contracted grid-limit protection |
| 2 | Critical backup reserve |
| 3 | Flexible-contract dispatch |
| 4 | Electricity-price optimisation |
| 5 | PV self-consumption |
A 500kW BESS cannot promise the same 500kW simultaneously to production support and congestion management.
The EMS should define:
- Minimum backup SOC
- Minimum production-support SOC
- Maximum charging power
- Dispatch availability
- Recovery charging
- Communication-failure behaviour
The PCS engineering architecture must support the required power commands and operating boundaries.
Compare Single-Site and Shared BESS
A single-site BESS serves one factory, one load profile and one control hierarchy.
A shared energy-hub BESS serves several companies using a combined transport-capacity limit.
The Dutch group transport agreement allows multiple large users to share contracted transport capacity while keeping their individual physical connections. Group members decide how the shared capacity is allocated.
A shared BESS therefore requires agreement on:
- Ownership
- EMS authority
- Power allocation
- SOC priority
- Metering
- Degradation cost
- Contract liability
The control system cannot resolve an incomplete commercial agreement.
Use Flex-e Before Freezing the BESS
Flex-e supports three project stages:
- Flexibility scan
- Feasibility study
- Flexibility measures
Applications for the 2026 programme run from May 6 to October 15, subject to the published conditions. The scan and study are intended to identify how much electricity can be moved and which measures are technically practical.
The recommended sequence is:
Load study → Flexibility scan → Contract review → BESS design → RFQ
It should not be:
Choose battery → Apply for support → Force the equipment into the operating profile
Funding eligibility does not prove technical suitability.
Know When a BESS Will Not Work
A commercial energy storage system may be unsuitable when:
- The factory remains near its grid limit all day.
- No reliable charging window exists.
- The additional load runs continuously.
- Transformer capacity is already inadequate.
- Backup and grid services compete for the same SOC.
- The battery would need to replace a mandatory grid upgrade.
Alternative measures may include:
- Production rescheduling
- Thermal storage
- Controlled EV charging
- Internal electrical upgrades
- On-site generation
- A group transport agreement
A credible preliminary review may conclude that a battery is not the correct solution.
Prepare the RFQ Data Pack
The RFQ should be based on measured operating data.
| Required input | Engineering purpose |
|---|---|
| 12 months of 15-minute data | Identify peaks and charging windows |
| Contracted import capacity | Define the grid limit |
| New-load schedule | Calculate the residual deficit |
| Single-line diagram | Define the connection architecture |
| Transformer data | Verify internal electrical capacity |
| Flexible-load list | Reduce unnecessary battery sizing |
| PV generation profile | Identify alternative charging energy |
| Backup requirement | Establish minimum SOC |
| Flexible-contract terms | Define dispatch obligations |
The commercial energy storage procurement guide can be used after these inputs are complete.
Register the Battery System
Battery systems rated at 0.8kW or more must be registered in the Netherlands.
The applicable registration category depends on system power. RVO identifies systems from 0.8kW to below 1MW as Type A, with higher-power systems placed in other categories.
Registration does not replace:
- Network-operator review
- Flexible-contract negotiation
- Internal electrical engineering
- Local site requirements
The EPC should confirm the applicable process before commissioning.
Select the System From the Deficit
MegSolid product selection should follow the verified power deficit and duration.
| Verified requirement | Preliminary direction |
|---|---|
| Up to 100kW | Evaluate ESSA0100B-0215 |
| 100–125kVA | Evaluate the 261.24kWh liquid-cooled system |
| 150–500kW | Evaluate an engineered battery system with MEGA PCS |
| Above 500kW | Compare pooled cabinets and containerized BESS |
ESSA0100B-0215
The ESSA0100B-0215 outdoor cabinet is rated at 100kW and 215.04kWh.
Its verified configuration includes:
- 280Ah LFP cells
- 768V nominal DC voltage
- Intelligent air cooling
- 0–45°C operating range
- IP54 enclosure
It must not be described as liquid-cooled or hybrid solid-state.
261.24kWh C&I System
The 261.24kWh liquid-cooled system provides 125kVA rated AC capacity.
Its verified configuration includes:
- 314Ah LFP cells
- 832V nominal DC voltage
- Liquid cooling
- Up to 10 units in parallel
- 90% maximum system efficiency
The 90% figure must not be described as round-trip efficiency.
Containerized BESS
The containerized BESS range includes:
- ESSCO500B-1075: 500kW／1.0752MWh
- ESSC1000B-2150: 1MW／2.1504MWh
These systems use intelligent air cooling and a 400V rated AC interface. Final suitability depends on site voltage, transformer scope and charging restrictions.
These are preliminary product directions, not project-fit guarantees.
Conclusion
A Dutch factory should not begin with the battery model.
It should begin with:
Grid limit → Load profile → Flexible loads → Power deficit → Recharge window → EMS priority → BESS selection
A battery is useful only when it can supply the constrained load and recover before the next production cycle.
That is the difference between purchasing battery capacity and engineering a workable commercial energy storage system.
FAQ
Q1: Can a BESS increase a Dutch factory’s contracted grid capacity?
No. A BESS does not change the contracted transport capacity. It temporarily supplies part of the factory load so that grid import remains below the agreed limit.
Q2: What data are required before sizing a BESS for Dutch grid congestion?
- At least 12 months of 15-minute load data
- Contracted grid import and export capacity
- Existing and planned production loads
- Production schedules
- Single-line diagram
- Transformer rating and loading
- Available battery charging window
- Flexible-contract requirements
Q3: Why is 15-minute load data more useful than monthly electricity bills?
Monthly bills show total energy consumption but do not reveal short demand peaks, production timing or available battery charging headroom. BESS power and energy must be calculated from interval data.
Q4: How is the required BESS power calculated?
A preliminary calculation is: Required BESS power = Existing load + New load − Permitted grid import + Engineering margin The final PCS rating must also consider load steps, reactive power, overload requirements and site operating conditions.
Q5: How is the required battery energy calculated?
Battery energy depends on the power deficit and its duration. For example, a 120kW deficit lasting four hours requires approximately 480kWh of AC energy before accounting for SOC limits, conversion losses, auxiliary consumption and end-of-life capacity.
Q6: Why is the battery recharge window important?
The battery must recover the energy used during production before the next constrained operating period. If the factory remains close to its contracted limit after discharge, the available charging power may be too low.
Q7: Should flexible loads be moved before selecting the battery?
Yes. Rescheduling EV charging, electric heating, chillers, air compressors or batch processes can reduce the residual power deficit and prevent unnecessary BESS oversizing.
Q8: Can one BESS support factory expansion and a flexible electricity contract?
Yes, but the EMS must reserve separate power and SOC for each service. It must also define which service has priority when production support and network-operator dispatch occur at the same time.
Q9: When is a commercial energy storage system unsuitable for grid congestion?
- The factory remains near its contracted grid limit throughout the day
- No reliable battery charging window exists
- The additional load operates continuously
- The transformer, switchgear or cables are undersized
- Backup and grid services require the same SOC reserve
- A mandatory grid upgrade cannot be avoided by installing storage
Q10: What should be included in a Dutch factory BESS RFQ?
- Required AC discharge power
- Required discharge duration
- Maximum permitted grid charging power
- Required SOC recovery time
- Site voltage and transformer data
- Backup reserve requirement
- Flexible-contract operating conditions
- EMS meter and communication interfaces
- Supplier and EPC responsibility boundaries
Q11: How can a Dutch factory expand when grid capacity is limited?
The factory should first identify flexible loads, calculate the remaining power deficit and use a BESS only for the demand that cannot be rescheduled. The design must also prove that the battery can recharge without exceeding the contracted grid limit.
Q12: What is the biggest BESS sizing mistake under Dutch grid congestion?
The biggest mistake is calculating only the required discharge power and energy. A viable design must also calculate the available charging power and confirm that the battery can recover its SOC before the next production period.
Q13: Can several Dutch companies share one BESS?
Yes. Companies participating in an energy hub or group transport arrangement can use a shared BESS, but ownership, power allocation, SOC priority, metering, EMS authority and contractual responsibility must be defined.
